I'm trying to implement a collapsible TitleWindow popup by adding a handle to the top right corner of a Panel control. Unfortunately, the image that I add as the hand开发者_开发技巧le doesn't show up when the control is drawn. I can trigger a redraw by changing the source of the image, so apparently it's there, but it's somehow hidden.
Is there a way to make this Image control visible to the user?
Here's the code for the window:
package
{
import mx.containers.Panel;
import mx.controls.Image;
public class CollapsableWindow extends Panel
{
public function CollapsableWindow()
{
super();
}
public var close:Image;
protected override function createChildren():void
{
super.createChildren();
close = new Image();
close.source = "/assets/close.png";
close.x = this.width - 20;
close.y = 8;
this.titleBar.addChildAt(close, 0);
}
}
}
You need to create your button in the createChildren method, then position it in the updateDisplayList method:
/**
* Creates the button and adds it to the titlebar
*/
override protected function createChildren():void
{
super.createChildren();
this.myButton = new Button();
this.myButton.addEventListener(MouseEvent.CLICK, onButtonClick);
this.titleBar.addChild(this.myButton);
}
/**
* Sizes and positions the button on the titlebar
*/
override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number):void
{
super.updateDisplayList(unscaledWidth, unscaledHeight);
this.myButton.setActualSize(myButton.getExplicitOrMeasuredWidth(),
myButton.getExplicitOrMeasuredHeight());
// Position the button
var y:int = 4;
var x:int = this.width - this.myButton.width - 2;
this.myButton.move(x, y);
}
I've had issues with PNG's not showing up in our app. Every once in a while, all our PNG's disappear. To test whether you're code suffers the same problem, try using a test image that's a GIF or other format. If it works then you're having the same issue I've run into dozens of times.
On our project, we solve this in two ways:
- A workaround. Toggle your project's SDK version and, for some odd reason, that fixes it
- So, for example, we use SDK 3.6
- I right click on the project, chose properties and go to the Flex SDK section
- From there I switch to ANY OTHER SDK version (say Flex 3.2) and choose ok
- This triggers an automatic build (with some kind of mysterious PNG-fixing power)
- Then I go back into the project properties and return it to our version.
- 8 times out of 10 this restores the PNG images
- This worked even when we were using Flex SDK 3.4 and 3.5
- A fix. Change your PNG format to PNG-24
- It seems the root problem is related to using the PNG-8 format
- For our images, I open the original in Photoshop press CMD-Shft-Ctrl-S, invoking "Save For Web..."
- Then I choose PNG-24 for the format, instead of PNG-8
- A similar process should work in any other image editing program
I hope that helps in some way,
-- gMale
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