Flex - DataGrid Control


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Introduction

The DataGrid control displays a row of column headings above a scrollable grid.

Class declaration

Following is the declaration for spark.components.DataGrid class:

public class DataGrid   
   extends SkinnableContainerBase 
      implements IFocusManagerComponent, IIMESupport

Public properties

S.N.Property & Description
1

columnsLength : int

[read-only] Returns the value of columns.length if the columns IList was specified, otherwise 0.

2

dataProvider : IList

A list of data items that correspond to the rows in the grid.

3

dataProviderLength : int

[read-only] Returns the value of dataProvider.length if the dataProvider IList was specified, otherwise 0.

4

dataTipField : String

The name of the field in the data provider to display as the datatip.

5

dataTipFunction : Function

Specifies a callback function to run on each item of the data provider to determine its data tip.

6

editable : Boolean

The default value for the GridColumn editable property, which indicates if a corresponding cell's data provider item can be edited.

7

editorColumnIndex : int

[read-only] The zero-based column index of the cell that is being edited.

8

editorRowIndex : int

[read-only] The zero-based row index of the cell that is being edited.

9

enableIME : Boolean

[read-only] A flag that indicates whether the IME should be enabled when the component receives focus.

10

imeMode : String

The default value for the GridColumn imeMode property, which specifies the IME (Input Method Editor) mode.

11

itemEditor : IFactory

The default value for the GridColumn itemEditor property, which specifies the IGridItemEditor class used to create item editor instances.

12

itemEditorInstance : IGridItemEditor

[read-only] A reference to the currently active instance of the item editor, if it exists.

13

itemRenderer : IFactory

The item renderer that's used for columns that do not specify one.

14

preserveSelection : Boolean

If true, the selection is preserved when the data provider refreshes its collection.

15

requestedColumnCount : int

The measured width of this grid is large enough to display the first requestedColumnCount columns.

16

requestedMaxRowCount : int

The measured height of the grid is large enough to display no more than requestedMaxRowCount rows.

17

requestedMinColumnCount : int

The measured width of this grid is large enough to display at least requestedMinColumnCount columns.

18

requestedMinRowCount : int

The measured height of this grid is large enough to display at least requestedMinRowCount rows.

19

requestedRowCount : int

The measured height of this grid is large enough to display the first requestedRowCount rows.

20

requireSelection : Boolean

If true and the selectionMode property is not GridSelectionMode.NONE, an item must always be selected in the grid.

21

resizableColumns : Boolean

Indicates whether the user can change the size of the columns.

22

rowHeight : Number

If variableRowHeight is false, then this property specifies the actual height of each row, in pixels.

23

selectedCell : CellPosition

If selectionMode is GridSelectionMode.SINGLE_CELL or GridSelectionMode.MULTIPLE_CELLS, returns the first selected cell starting at row 0 column 0 and progressing through each column in a row before moving to the next row.

24

selectedCells : Vector.<CellPosition>

If selectionMode is GridSelectionMode.SINGLE_CELL or GridSelectionMode.MULTIPLE_CELLS, returns a Vector of CellPosition Objects representing the positions of the selected cells in the grid.

25

selectedIndex : int

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, returns the rowIndex of the first selected row.

26

selectedIndices : Vector.<int>

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, returns a Vector of the selected rows indices.

27

selectedItem : Object

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, returns the item in the the data provider that is currently selected or undefined if no rows are selected.

28

selectedItems : Vector.<Object>

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, returns a Vector of the dataProvider items that are currently selected.

29

selectionLength : int

[read-only] If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, returns the number of selected rows.

30

selectionMode : String

The selection mode of the control.

31

showDataTips : Boolean

If true then a dataTip is displayed for all visible cells.

32

sortableColumns : Boolean

Specifies whether the user can interactively sort columns.

33

typicalItem : Object

The grid's layout ensures that columns whose width is not specified is wide enough to display an item renderer for this default data provider item.

34

variableRowHeight : Boolean

If true, each row's height is the maximum of preferred heights of the cells displayed so far.

35

columns : IList

The list of GridColumn Objects displayed by this grid.

Public methods

S.N.Method & Description
1

DataGrid()

Constructor.

2

addSelectedCell(rowIndex:int, columnIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_CELL or GridSelectionMode.MULTIPLE_CELLS, adds the cell to the selection and sets the caret position to the cell.

3

addSelectedIndex(rowIndex:int):Boolean

If selectionMode is GridSelectionMode.MULTIPLE_ROWS, adds this row to the selection and sets the caret position to this row.

4

clearSelection():Boolean

Removes all of the selected rows and cells, if selectionMode is not GridSelectionMode.NONE.

5

endItemEditorSession(cancel:Boolean = false):Boolean

Closes the currently active editor and optionally saves the editor's value by calling the item editor's save() method.

6

ensureCellIsVisible(rowIndex:int, columnIndex:int = -1):void

If necessary, set the verticalScrollPosition and horizontalScrollPosition properties so that the specified cell is completely visible.

7

invalidateCell(rowIndex:int, columnIndex:int):void

If the specified cell is visible, it is redisplayed.

8

invalidateTypicalItem():void

9

removeSelectedCell(rowIndex:int, columnIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_CELL or GridSelectionMode.MULTIPLE_CELLS, removes the cell from the selection and sets the caret position to the cell.

10

removeSelectedIndex(rowIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, removes this row from the selection and sets the caret position to this row.

11

selectAll():Boolean

If selectionMode is GridSelectionMode.MULTIPLE_ROWS, selects all rows and removes the caret or if selectionMode is GridSelectionMode.MULTIPLE_CELLS selects all cells and removes the caret.

12

selectCellRegion(rowIndex:int, columnIndex:int, rowCount:uint, columnCount:uint):Boolean

If selectionMode is GridSelectionMode.MULTIPLE_CELLS, sets the selection to all the cells in the cell region and the caret position to the last cell in the cell region.

13

selectIndices(rowIndex:int, rowCount:int):Boolean

If selectionMode is GridSelectionMode.MULTIPLE_ROWS, sets the selection to the specfied rows and the caret position to endRowIndex.

14

selectionContainsCell(rowIndex:int, columnIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_CELL or GridSelectionMode.MULTIPLE_CELLS, returns true if the cell is in the current selection.

15

selectionContainsCellRegion(rowIndex:int, columnIndex:int, rowCount:int, columnCount:int):Boolean

If selectionMode is GridSelectionMode.MULTIPLE_CELLS, returns true if the cells in the cell region are in the current selection.

16

selectionContainsIndex(rowIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, returns true if the row at index is in the current selection.

17

selectionContainsIndices(rowIndices:Vector.<int>):Boolean

If selectionMode is GridSelectionMode.MULTIPLE_ROWS, returns true if the rows in indices are in the current selection.

18

setSelectedCell(rowIndex:int, columnIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_CELL or GridSelectionMode.MULTIPLE_CELLS, sets the selection and the caret position to this cell.

19

setSelectedIndex(rowIndex:int):Boolean

If selectionMode is GridSelectionMode.SINGLE_ROW or GridSelectionMode.MULTIPLE_ROWS, sets the selection and the caret position to this row.

20

sortByColumns(columnIndices:Vector.<int>, isInteractive:Boolean = false):Boolean

Sort the DataGrid by one or more columns, and refresh the display.

21

startItemEditorSession(rowIndex:int, columnIndex:int):Boolean

Starts an editor session on a selected cell in the grid.

Protected Methods

S.N.Method & Description
1

commitCaretPosition(newCaretRowIndex:int, newCaretColumnIndex:int):void

Updates the grid's caret position.

2

commitInteractiveSelection(selectionEventKind:String, rowIndex:int, columnIndex:int, rowCount:int = 1, columnCount:int = 1):Boolean

In response to user input (mouse or keyboard) which changes the selection, this method dispatches the selectionChanging event.

Events

S.N.Event & Description
1

caretChange

Dispatched by the grid skin part when the caret position, size, or visibility has changed due to user interaction or being programmatically set.

2

gridClick

Dispatched by the grid skin part when the mouse is clicked over a cell.

3

gridDoubleClick

Dispatched by the grid skin part when the mouse is double-clicked over a cell.

4

gridItemEditorSessionCancel

Dispatched after the item editor has been closed without saving its data.

5

gridItemEditorSessionSave

Dispatched after the data in item editor has been saved into the data provider and the editor has been closed.

6

gridItemEditorSessionStart

Dispatched immediately after an item editor has been opened.

7

gridItemEditorSessionStarting

Dispatched when a new item editor session has been requested.

8

gridMouseDown

Dispatched by the grid skin part when the mouse button is pressed over a grid cell.

9

gridMouseDrag

Dispatched by the grid skin part after a gridMouseDown event if the mouse moves before the button is released.

10

gridMouseUp

Dispatched by the grid skin part after a gridMouseDown event when the mouse button is released, even if the mouse is no longer within the grid.

11

gridRollOut

Dispatched by the grid skin part when the mouse leaves a grid cell.

12

gridRollOver

Dispatched by the grid skin part when the mouse enters a grid cell.

13

selectionChange

Dispatched when the selection has changed.

14

selectionChanging

Dispatched when the selection is going to change.

15

sortChange

Dispatched after the sort has been applied to the data provider's collection.

16

sortChanging

Dispatched before the sort has been applied to the data provider's collection.

Methods inherited

This class inherits methods from the following classes:

  • spark.components.supportClasses.SkinnableContainerBase

  • spark.components.supportClasses.SkinnableComponent

  • mx.core.UIComponent

  • mx.core.FlexSprite

  • flash.display.Sprite

  • flash.display.DisplayObjectContainer

  • flash.display.InteractiveObject

  • flash.display.DisplayObject

  • flash.events.EventDispatcher

  • Object

Flex DataGrid Control Example

Let us follow the following steps to check usage of DataGrid control in a Flex application by creating a test application:

StepDescription
1Create a project with a name HelloWorld under a package com.tutorialspoint.client as explained in the Flex - Create Application chapter.
2Modify HelloWorld.mxml as explained below. Keep rest of the files unchanged.
3Compile and run the application to make sure business logic is working as per the requirements.

Following is the content of the modified mxml file src/com.tutorialspoint/HelloWorld.mxml.

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
   xmlns:s="library://ns.adobe.com/flex/spark"
   xmlns:mx="library://ns.adobe.com/flex/mx"
   width="100%" height="100%" minWidth="500" minHeight="500"
   >
   <fx:Style source="/com/tutorialspoint/client/Style.css"/>	
   <fx:Script>
      <![CDATA[
         import mx.collections.ArrayCollection;
         [Bindable]
         public var data:ArrayCollection = new ArrayCollection(
         [   
            {value:"France", code:"FR"},
            {value:"Japan", code:"JP"},
            {value:"India", code:"IN"},
            {value:"Russia", code:"RS"},
            {value:"United States", code:"US"}		
         ]                
         );
      ]]>
   </fx:Script>
   <s:BorderContainer width="630" height="480" id="mainContainer" 
      styleName="container">
      <s:VGroup width="100%" height="100%" gap="50" 
         horizontalAlign="center" verticalAlign="middle">
         <s:Label id="lblHeader" text="Complex Controls Demonstration" 
            fontSize="40" color="0x777777" styleName="heading"/>
         <s:Panel id="dataGridPanel" title="Using DataGrid" 
            width="500" height="300">
            <s:layout>
               <s:VerticalLayout  gap="10" verticalAlign="middle" 
                  horizontalAlign="center"/>							
            </s:layout>					
            <s:DataGrid dataProvider="{data}" id="dataGrid">
               <s:columns>
                  <s:ArrayList>
                     <s:GridColumn dataField="code" width="100" 
                        headerText="Code" />
                     <s:GridColumn dataField="value" width="200" 
                        headerText="Value" />
                  </s:ArrayList>
               </s:columns>
            </s:DataGrid>
            <s:HGroup width="60%">
               <s:Label text="Code :"/> 
               <s:Label text="{dataGrid.selectedItem.code}"
                  fontWeight="bold"/>
               <s:Label text="Value :"/> 
               <s:Label text="{dataGrid.selectedItem.value}"
                  fontWeight="bold"/>						
            </s:HGroup>
         </s:Panel>
      </s:VGroup>	 
   </s:BorderContainer>	
</s:Application>

Once you are ready with all the changes done, let us compile and run the application in normal mode as we did in Flex - Create Application chapter. If everything is fine with your application, this will produce following result: [ Try it online ]

Flex DataGrid Control
flex_complex_controls.htm

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