Login
Login
Help Center
 > 
 > 
4. Blocks Coding with Web App > 
Arrays
Arrays
Print

This documentation details array operations, including creation, reading, modifying values, and performing operations like finding locations, reversing, and managing array elements.

Create

Setting a number array

Set list to array of

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><block type=\"lists_create_with\"><mutation items=\"2\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value><value name=\"ADD1\"><shadow type=\"math_number\"><field name=\"NUM\">1</field></shadow></value></block></value></block></xml>"}

This block is used to set the number array into variable. 

Parameters: Number (Default:0, 1)
Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>value</variable><variable>dateTimeOffset</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"2\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value><value name=\"ADD1\"><shadow type=\"math_number\"><field name=\"NUM\">1</field></shadow></value></block></value><next><block type=\"pxt_controls_for_of\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">value</field></shadow></value><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"DateTime_DateTimeOffset_toString\"><value name=\"dateTimeOffset\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\" disabled=\"true\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">value</field></block></value></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Set list to array of - Output

Setting a Text Array

Set text list to array of

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"variables_set\"><field name=\"VAR\">text_list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value></block></xml>"}

This block is used to set the text array into variable. 

Parameters: String (Default: a, b, c)
Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>text_list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">text_list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">text_list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">text_list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Set text list to array of - Output

Creating New Array

Empty array

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><block type=\"lists_create_with\"><mutation items=\"2\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value><value name=\"ADD1\"><shadow type=\"math_number\"><field name=\"NUM\">1</field></shadow></value></block></value></block></xml>"}

This block is used to create a new array. 

Parameters: Screen Item
Output: Array
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>array</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">array</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"2\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">text 1</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">text 2</field></shadow></value></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">array</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">array</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Empty array - Output

Read

Counting the Length of an Array

Length of array list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used show the number of items in the array.

Parameters: Screen Item (Array)
Output: Number
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>length</variable><variable>dateTimeOffset</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">length</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"DateTime_DateTimeOffset_toString\"><value name=\"dateTimeOffset\"><block type=\"variables_get\"><field name=\"VAR\">length</field></block></value></block></value></block></value></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Length of array list - Output

Showing the Value with the Selected Index

List get value at

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value></block></xml>"}

This block is used to show the value at the given index in an array. 

Parameters: 

  • Screen Item (Array)
  • Number

Output: Screen Item
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value></block></value></block></value></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List get value at - Output

Showing the Value that will be Removed

List get and remove value at

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_removeat\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"index\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value></block></xml>"}

This block is used to show and remove the value at the certain index.

Parameters: 

  • Screen Item (Array)
  • Number

Output: Screen Item
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"array_removeat\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"index\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value></block></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><shadow type=\"text\"><field name=\"TEXT\">After removing the value, the remaining values are:</field></shadow></value></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List get and remove value at - Output

Showing and Removing the Last Item

Get and remove last value from list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_pop\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to show and remove the last value inside array.

Parameters: Screen Item (Array)
Output: Screen Item
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"array_pop\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><shadow type=\"text\"><field name=\"TEXT\">After removing the value, the remaining values are:</field></shadow></value></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Get and remove last value from list - Output

Showing and Removing the First Item

Get and remove first value from list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_shift\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to show and remove the first value inside array. 

Parameters: Screen Item (Array)
Output: Screen Item
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"array_shift\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><shadow type=\"text\"><field name=\"TEXT\">After removing the value, the remaining values are:</field></shadow></value></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Get and remove first value from list - Output

Showing a Random Value

Get random value from list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_pickRandom\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to show a random value from the array. 

Parameters: Screen Item (Array)
Output: Screen Item
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"array_pickRandom\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value></block></value></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Get random value from list - Output

Modify

Modifying the Value Inside Array

List set value at 0 to

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"lists_index_set\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value></block></xml>"}

This block is used to modify the value at the selected location in the array.

Parameters: 

  • Screen Item (Array)
  • Condition:
    • Number (Default: 0)
    • Screen Item

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"lists_index_set\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value><value name=\"VALUE\"><shadow type=\"text\"><field name=\"TEXT\">d</field></shadow></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List set value at 0 to - Output

Inserting the Value at the End

List add value … to end

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_push\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to add the value at the end of the array.

Parameters: 

  • Screen Item (Array)
  • Screen Item 

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_push\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"value\"><shadow type=\"text\"><field name=\"TEXT\">END</field></shadow></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List add value to end - Output

Deleting Last Value

Remove last value from list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_pop_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to delete the last value in the array. 

Parameters: 

  • Screen Item (Array)
  • Screen Item

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_pop_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Remove last value from list - Output

Deleting First Value

Remove first value from list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_shift_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to delete the first value in the array. 

Parameters: 

  • Screen Item (Array)
  • Screen Item

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_shift_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Remove first value from list - Output

Adding Value at the Beginning

List insert … at beginning

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_unshift\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used add one value at the beginning of an array. 

Parameters: 

  • Screen Item (Array)
  • Screen Item

Output: Screen Item
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>insert</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">insert</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"array_unshift\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"value\"><shadow type=\"text\"><field name=\"TEXT\">START</field></shadow></value></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List insert at beginning - Output

Inserting Value at the Beginning

List insert … at beginning

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_unshift_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used add one value at the beginning of an array. 

Parameters: 

  • Screen Item (Array)
  • Screen Item

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_unshift_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"value\"><shadow type=\"text\"><field name=\"TEXT\">STARTING</field></shadow></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List insert at beginning - Output (no output)

Adding Value in the Certain Place

List insert at 0 value

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_unshift_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to add one value at the certain location. 

Parameters: 

  • Screen Item (Array)
  • Condition: Number (Default: 0)
  • Screen Item

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_insertAt\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"index\"><shadow type=\"math_number\"><field name=\"NUM\">1</field></shadow></value><value name=\"value\"><shadow type=\"text\"><field name=\"TEXT\">hello</field></shadow></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List insert at 0 value - Output

Deleting Value at a Certain Location

List remove value at

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_removeat_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"index\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow></value></block></xml>"}

This block is used to delete the value at a certain location.

Parameters: 

  • Screen Item (Array)
  • Condition: Number (Default: 0)

Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_removeat_statement\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"index\"><shadow type=\"math_number\"><field name=\"NUM\">1</field></shadow></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List remove value at - Output

Operations

Finding the Location of a Value

List find index of

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_indexof\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to find the location of a value. 

Parameters: 

  • Screen Item (Array)
  • Condition: String/Number (Default: 0)

Output: Number
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>find</variable><variable>dateTimeOffset</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">find</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"array_indexof\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"value\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"DateTime_DateTimeOffset_toString\"><value name=\"dateTimeOffset\"><block type=\"variables_get\"><field name=\"VAR\">find</field></block></value></block></value></block></value></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

List find index of - Output

Reversing the Array

Reverse list

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><block type=\"array_reverse\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></xml>"}

This block is used to reverse the value in the array. 

Parameters: Screen Item (Array)
Output: N/A
Sample code:

{"blocks":"<xml xmlns=\"https://developers.google.com/blockly/xml\"><variables><variable>mainLayout</variable><variable>mainScreen</variable><variable>list</variable><variable>index</variable></variables><block type=\"pxt-on-start\" x=\"0\" y=\"0\"><statement name=\"HANDLER\"><block type=\"variables_set\"><field name=\"VAR\">mainLayout</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"ScreenItem_createLayout\"/></value><next><block type=\"variables_set\"><field name=\"VAR\">mainScreen</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"Screen_create\"><value name=\"label\"><shadow type=\"text\"><field name=\"TEXT\">Main</field></shadow></value><value name=\"layout\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value></block></value><next><block type=\"variables_set\"><field name=\"VAR\">list</field><value name=\"VALUE\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_create_with\"><mutation items=\"3\" horizontalafter=\"3\"/><value name=\"ADD0\"><shadow type=\"text\"><field name=\"TEXT\">a</field></shadow></value><value name=\"ADD1\"><shadow type=\"text\"><field name=\"TEXT\">b</field></shadow></value><value name=\"ADD2\"><shadow type=\"text\"><field name=\"TEXT\">c</field></shadow></value></block></value><next><block type=\"array_reverse\"><value name=\"list\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><next><block type=\"pxt_controls_for\"><value name=\"VAR\"><shadow type=\"variables_get_reporter\"><field name=\"VAR\">index</field></shadow></value><value name=\"TO\"><shadow type=\"math_whole_number\"><field name=\"NUM\">0</field></shadow><block type=\"lists_length\"><value name=\"VALUE\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value></block></value><statement name=\"DO\"><block type=\"ScreenItem_Layout_add\"><value name=\"this\"><block type=\"variables_get\"><field name=\"VAR\">mainLayout</field></block></value><value name=\"item\"><block type=\"Control_createTextBlock\"><mutation xmlns=\"http://www.w3.org/1999/xhtml\" _expanded=\"1\" _input_init=\"true\"></mutation><value name=\"text\"><block type=\"lists_index_get\"><value name=\"LIST\"><block type=\"variables_get\"><field name=\"VAR\">list</field></block></value><value name=\"INDEX\"><shadow type=\"math_number\"><field name=\"NUM\">0</field></shadow><block type=\"variables_get\"><field name=\"VAR\">index</field></block></value></block></value></block></value></block></statement></block></next></block></next></block></next></block></next></block></statement></block></xml>"}

The output:

Reverse list - Output

Table of Content