Manipulating a DataProvider

You can add items to a DataProvider with the addItem() and addItemAt() methods. The following example adds items that a user enters into the text field of an editable ComboBox. It assumes a ComboBox has been dragged onto the Stage and given an instance name of aCb.

import fl.data.DataProvider;
import fl.events.ComponentEvent;

var items:Array = [
{label:"Roger"},
{label:"Carolyn"},
{label:"Darrell"},
{label:"Rebecca"},
{label:"Natalie"},
{label:"Mitchell"},
];
aCb.dataProvider = new DataProvider(items);
 
aCb.addEventListener(ComponentEvent.ENTER, newItemHandler);
  
function newItemHandler(event:ComponentEvent):void {
    var newRow:int = event.target.length + 1;
     event.target.addItemAt({label:event.target.selectedLabel},
        event.target.length);
}

You can also replace and remove items in a component through its DataProvider. The following example implements two separate List components, listA and listB, and provides a Button labeled Sync. When a user clicks the Button, the example uses the replaceItemAt() method to replace the items in listB with the items in listA. If listA is longer than listB, the example calls the addItem() method to add the extra items to listB. If listB is longer than listA, the example calls the removeItemAt() method to remove the extra items in ListB.

// Requires the List and Button components to be in the library

import fl.controls.List;
import fl.controls.Button;
import flash.events.Event;
import fl.data.DataProvider;

var listA:List = new List();
var listB:List = new List();
var syncButton:Button = new Button();
syncButton.label = "Sync";

var itemsA:Array = [
{label:"David"},
{label:"Colleen"},
{label:"Sharon"},
{label:"Ronnie"},
{label:"James"},
];
var itemsB:Array = [
{label:"Roger"},
{label:"Carolyn"},
{label:"Darrell"},
{label:"Rebecca"},
{label:"Natalie"},
{label:"Mitchell"},
];
listA.dataProvider = new DataProvider(itemsA);
listB.dataProvider = new DataProvider(itemsB);

addChild(listA);
addChild(listB);
addChild(syncButton);

listA.move(100, 100);
listB.move(250, 100);
syncButton.move(175, 220);

syncButton.addEventListener(MouseEvent.CLICK, syncHandler);

function syncHandler(event:MouseEvent):void {
    var i:uint = 0;
    if(listA.length > listB.length) {     //if listA is longer, add items to B
        while(i < listB.length) {
            listB.dataProvider.replaceItemAt(listA.dataProvider.getItemAt(i), i);
            ++i;
        }
        while(i < listA.length) {
            listB.dataProvider.addItem(listA.dataProvider.getItemAt(i++));
        }
    } else if(listA.length == listB.length) { //if listA and listB are equal length
        while(i < listB.length) {
            listB.dataProvider.replaceItemAt(listA.dataProvider.getItemAt(i), i);
            ++i;
        }
    } else {                //if listB is longer, remove extra items from B
        while(i < listA.length) {
            listB.dataProvider.replaceItemAt(listA.dataProvider.getItemAt(i), i);
            ++i;
        }
        while(i < listB.length) {
            listB.dataProvider.removeItemAt(i++);
        }
    }
}

You can also merge with and sort a DataProvider using the merge(), sort(), and sortOn() methods. The following example populates two DataGrid instances (aDg and bDg) with partial rosters for two softball teams. It adds a Button with a label of Merge, and when the user clicks it, the event handler (mrgHandler) merges the roster for bDg with the roster for aDg and sorts the resulting DataGrid on the Name column.

import fl.data.DataProvider;
import fl.controls.DataGrid;
import fl.controls.Button;

var aDg:DataGrid = new DataGrid();
var bDg:DataGrid = new DataGrid();
var mrgButton:Button = new Button();
addChild(aDg);
addChild(bDg);
addChild(mrgButton);
bldRosterGrid(aDg);
bldRosterGrid(bDg);
var aRoster:Array = new Array();
var bRoster:Array = new Array();
aRoster = [
        {Name:"Wilma Carter", Bats:"R", Throws:"R", Year:"So", Home: "Redlands, CA"}, 
        {Name:"Sue Pennypacker", Bats:"L", Throws:"R", Year:"Fr", Home: "Athens, GA"},
        {Name:"Jill Smithfield", Bats:"R", Throws:"L", Year:"Sr", Home: "Spokane, WA"},
        {Name:"Shirley Goth", Bats:"R", Throws:"R", Year:"Sr", Home: "Carson, NV"}
];
bRoster = [
        {Name:"Angelina Davis", Bats:"R", Throws:"R", Year:"So", Home: "Odessa, TX"},
        {Name:"Maria Santiago", Bats:"L", Throws:"L", Year:"Sr", Home: "Tacoma, WA"},
        {Name:"Debbie Ferguson", Bats:"R", Throws:"R", Year: "Jr", Home: "Bend, OR"}
];
aDg.dataProvider = new DataProvider(aRoster);
bDg.dataProvider = new DataProvider(bRoster);
aDg.move(50,50);
aDg.rowCount = aDg.length;
bDg.move(50,200);
bDg.rowCount = bDg.length;
mrgButton.label = "Merge";
mrgButton.move(200, 315);
mrgButton.addEventListener(MouseEvent.CLICK, mrgHandler);

function bldRosterGrid(dg:DataGrid){
    dg.setSize(400, 300);
    dg.columns = ["Name", "Bats", "Throws", "Year", "Home"];
    dg.columns[0].width = 120;
    dg.columns[1].width = 50;
    dg.columns[2].width = 50;
    dg.columns[3].width = 40;
    dg.columns[4].width = 120;
};

function mrgHandler(event:MouseEvent):void {
    aDg.dataProvider.merge(bDg.dataProvider);
    aDg.dataProvider.sortOn("Name");
}