flash simple button with text

Question

I have a simple Button in Flash cs5 - as3 called btn1 with a dynamic text called text_txt inside inside it.

The goal is simply to change the text however...

btn1.visible=true; // works fine
this.btn1.text_txt.text="hello"; // give a NULL error

My question is: how to programatically change the text that is inside that button ?

Solution 1

Because I have FlashDevelop I can only show you how to do everything programmatically.

If your dealing with a Sprite object(which I recommend) then the following is how you access a TextField in the Sprite object:

var textField:TextField = new TextField();
textField.name = "textField";
textField.mouseEnabled = false;

var rectangleShape:Shape = new Shape();
rectangleShape.graphics.beginFill(0xFF0000);
rectangleShape.graphics.drawRect(0, 0, 100, 25);
rectangleShape.graphics.endFill();

var buttonSprite:Sprite = new Sprite();
buttonSprite.addChild(rectangleShape);
buttonSprite.addChild(textField);
addChild(buttonSprite);

var tf:TextField = TextField(buttonSprite.getChildByName("textField"));
tf.text = "button sprite text";

First the TextField object called textField is instantiated and its name property is assigned the string "textField" which is the same as setting its instance name.

Next a Shape object called rectangleShape is instantiated which is graphically configured to look like a simple red rectangle.

Next a Sprite display object object called buttonSprite is instantiated and the textField and rectangleShape display objects are added to it. Then the Sprite display object container is added to the stage.

Finally the buttonSprite display object container's getChildByName() method is called and returns the textField display object. To do this the the textField display object's name property has to be given as the getChildByName() methods's argument. Next the returned textField object is stored in a local TextField object called tf which now gives you access to the textField.

[UPDATE]

The following is the approach for accessing a TextField object via SimpleButton object which is similar to accessing it via a Sprite object(I don't recommend this though):

var textField:TextField = new TextField();
textField.name = "textField";
textField.mouseEnabled = false;

var rectangleShape:Shape = new Shape();
rectangleShape.graphics.beginFill(0xFF0000);
rectangleShape.graphics.drawRect(0, 0, 100, 25);
rectangleShape.graphics.endFill();

var simpleButtonSprite:Sprite = new Sprite();
simpleButtonSprite.name = "simpleButtonSprite";
simpleButtonSprite.addChild(rectangleShape);
simpleButtonSprite.addChild(textField);

var simpleButton:SimpleButton = new SimpleButton();
simpleButton.upState = simpleButtonSprite;
simpleButton.overState = simpleButtonSprite;
simpleButton.downState = simpleButtonSprite;
simpleButton.hitTestState = simpleButtonSprite;
addChild(simpleButton);

// local simpleButtonSprite object
var sbs:DisplayObjectContainer = DisplayObjectContainer(simpleButton.upState);
//local textField object
var tf:TextField = TextField(sbs.getChildByName("textField"));  
tf.text = "simple button text ";

Solution 2

There is a simple way to access the SimpleButton's Children:

For example, in my SimpleButton (named _myButton) at its up State, I have a label (its instance name doesn't matter) and a Sprite (at layer 0):

var _container:DisplayObjectContainer = DisplayObjectContainer(_myButton.upState);
var _spt:Sprite = Sprite(_container.getChildAt(0));
var _lbl:Label = Label(_container.getChildAt(1));

Comments:
- You can access the diferent button states: upState, downState, hitTestState, overState;
- You can cast to DisplayObjectContainer in order to get the children;
- You cannot use (at least directly) getChildByName because the instance names will be generate dynamically.