DisplayObject snapshot in flex 3 - apache-flex

i'm creating a visual editor in flex and need to let users export thier projects into Image format. But i have one problem: size of the canvas is fixed and when user add element which is out of these sizes some scroll bars added. And user continue working on the project. but when he want to take snapshot of the canvas he just get the visible part ot the canvas with scrollbars. how to get image of the fullsize canvas?
The only solution i found is to check the positions and sizes of canvas child objects and rezise it to fit them. then take snap and resize back. But it hmmmm... too complicated i think. Is there some "easy methods"?
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical">
<mx:Script>
<![CDATA[
import mx.graphics.ImageSnapshot;
private function SnapshotButtonHandler():void
{
var snapshot:ImageSnapshot = ImageSnapshot.captureImage(AppCanvas);
var file:FileReference = new FileReference();
file.save(snapshot.data, "canvas.png");
}
]]>
</mx:Script>
<mx:Canvas id="AppCanvas" width="800" height="300" backgroundColor="0xFFFFFF">
<mx:Box x="750" y="100" width="100" height="100" backgroundColor="0xCCCCCC" />
</mx:Canvas>
<mx:Button id="SnapshotButton" label="take snapshot" click="SnapshotButtonHandler()" />
</mx:Application>

i would put one container into the scrollable canvas, that adapts it's size according to objects in it ... maybe even UIComponent would do the trick ... then do a snapshot of that container ... the canvas only adds the scrollbars, so to speak ...
greetz
back2dos

Solution i found
BaseCanvas - canvas with fixed height and width
EditCanvas - dynamic canvas which params depends on it's children position.
Snapshot takes from EditCanvas. Here part of code
private function SnapshotButtonHandler():void
{
var snapshot:ImageSnapshot = ImageSnapshot.captureImage(EditCanvas);
var file:FileReference = new FileReference();
file.save(snapshot.data, "canvas.png");
}
private function ResizeCanvas():void
{
for each (var child:* in AppCanvas.getChildren())
{
if ((child.x + child.width) > AppCanvas.width)
AppCanvas.width = child.x+child.width;
if ((child.y + child.height) > AppCanvas.height)
AppCanvas.height = child.y+child.height;
}
}
<mx:Canvas id="BaseCanvas" width="300" height="200">
<mx:Canvas id="EditCanvas" width="300" height="200" backgroundColor="0xFFFFF0" horizontalScrollPolicy="off" verticalScrollPolicy="off"/>
</mx:Canvas>

krishna: make sure you're targeting flash player 10 in your build path.

Related

Flex spark list to render images

I am new in flex. Currently i am going to build a flex album, but I get a problem about
the render in image by spark list.
the problem is this last 2~3 thumbs can not be properly displayed, as you can see as follows:
http://www.j-rich.com/Problem
and it will look like:
http://www.j-rich.com/Problem/show.jpg
for the source code, you can right click and choose view source in the demo
Any suggestion will be appreciated, thank you very much.
Sincerely,
Yuan-Hsu Liao
Add cachePolicy="on" to your Image control in ItemRenderer. But I don't recomend to use this kind of huge images as thumbnails. Looks like Flash has some limitations in this field.
This is correct for me, my resolution is 1920*1080. I use FLEX SDK4.5.1, flashplayer 11.8.
By the way, you should better override the set data function in the ItemRenderer, and set img source in the function, like this:
<?xml version="1.0" encoding="utf-8"?>
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark">
<s:layout>
<s:VerticalLayout/>
</s:layout>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.FlexEvent;
override public function set data(value:Object):void {
super.data = value;
var url:String = value as String;
img.source = url;
positionImg();
}
private function positionImg():void
{
this.ima.width = 136;
this.ima.height = 105;
this.ima.x = 0;
this.ima.y = 0;
}
]]>
</fx:Script>
<s:Group id="group" x="0" y="0" width="170" height="85">
<s:Image id="img" x="0" y="0" scaleMode="letterbox"/>
</s:Group>
</s:ItemRenderer>
ItemRenderer is recycled, so it's better to do some stuff in the set data()
Check whether ur Padding given is Correct...or else Adjust the same.

How to splice 2 mx canvas objects with repeat-x backgrounds?

I have 2 canvas objects that both contain a tiling image. My client recently requested that both the images be able to appear at the same time. I simply allowed them to be both enabled at the same time thinking they would tile appropriately but they do not.
After some careful thought I realized this is because they are of varying width so although my tiling image is 7 pixels in width, it may not always end at 7 pixels thus causing it to not appear to tile cleanly.
I can't just lop off the remainders because the imagery is being used to assess quantities of items (without going into too much detail) and having item 1 with 97 quantity next to item 2 with 200 quantity on one row compared to row 2 with item 1 having 100 quantity and item 2 having 300 quantity will show up strange to the end-user.
Does anyone know of how I could get started with maybe splicing the two canvas objects together or rather using 1 canvas object and then using BOTH background images and setting a percentWidth or something that the other one comes into affect?
You can use the copyPixels() method of the BitmapData class to achieve this sort of result. To do this, you need to load each image with a Loader. When the images are loaded, you have two Bitmap objects. From there, you access the corresponding BitmapData for each Bitmap and can splice them together.
After the splice, you create a new Bitmap object from the combined BitmapData. Then you feed the combined Bitmap to some other component. Unfortunately, a Canvas won't accept a Bitmap for its backgroundImage style. But you can add the combined Bitmap to a UIComponent or set it as the source of an Image component.
Finally, add either the UIComponent or Image to a Canvas. Since you can layer things on the Canvas, you effectively have a background image as long as place (and leave) the combined image at index 0 of the Canvas.
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="vertical"
minWidth="955" minHeight="600"
creationComplete="onCreationComplete()">
<mx:Script>
<![CDATA[
import mx.containers.Canvas;
import mx.controls.Image;
import mx.core.UIComponent;
import mx.events.FlexEvent;
private var loader1:Loader;
private var loader2:Loader;
private var bitmap1:BitmapData;
private var bitmap2:BitmapData;
protected function onCreationComplete():void
{
loader1 = new Loader();
loader1.load(new URLRequest("Android_Robot_100.png"));
loader1.contentLoaderInfo.addEventListener(Event.COMPLETE, onLoader1Complete, false,0,true);
loader2 = new Loader();
loader2.load(new URLRequest("rails.png"));
loader2.contentLoaderInfo.addEventListener(Event.COMPLETE, onLoader2Complete, false,0,true);
}
protected function onLoader1Complete(event:Event):void
{
bitmap1 = (loader1.content as Bitmap).bitmapData;
if (bitmap1 && bitmap2)
copyPixels();
}
private function onLoader2Complete(event:Event):void
{
bitmap2 = (loader2.content as Bitmap).bitmapData;
if (bitmap1 && bitmap2)
copyPixels();
}
protected function copyPixels():void
{
// false = non-transparent background
var combined:BitmapData = new BitmapData(200,200, false);
var sourceRect1:Rectangle = new Rectangle(0,0,bitmap1.width, bitmap1.height);
var sourceRect2:Rectangle = new Rectangle(0,0,bitmap2.width, bitmap2.height);
combined.copyPixels(bitmap1, sourceRect1, new Point(0,0));
combined.copyPixels(bitmap2, sourceRect2, new Point(bitmap1.width, 0));
var result:Bitmap = new Bitmap(combined);
var image:Image = new Image();
image.source = result;
var canvas:Canvas = new Canvas();
canvas.addChildAt(image, 0);
addChild(canvas);
// as an alternative, just add the bitmap to a UIComponent
// note you can't do this and the above at the same time,
// becuase the 'result` Bitmap can only be the child of one
// object, adding it to one thing removes it from the other...
// var uic:UIComponent = new UIComponent();
// uic.addChild(result);
// addChild(uic);
}
]]>
</mx:Script>
</mx:Application>
Ultimately I was overcomplicating it. I simply did this with masking like...
<mx:Canvas width="100%" height="100%">
<mx:Image id="myFirstUnrelatedImage" width="50%" height="65%" maintainAspectRatio="false"
verticalCenter="0" left="3"
source="#Embed('../assets/image1.png')" visible="true"/>
<!-- not sure why borderStyle here is required but it won't show up without? -->
<mx:Canvas id="image1mask" width="30%" height="94%"
borderStyle="none" visible="false"/>
<mx:Canvas id="image1" width="100%" height="100%"
minWidth="0" styleName="myStyle"
mask="{image1mask}"/>
<!-- not sure why borderStyle here is required but it won't show up without? -->
<mx:Canvas id="image2mask" width="20%" height="94%"
right="0" borderStyle="none" visible="false"
includeInLayout="false"/>
<mx:Canvas id="image2" width="100%" height="100%"
minWidth="0" styleName="myStyle2"
mask="{image2mask}"/>
</mx:Canvas>
Where my styles were controlling the backgroundImage and backgroundRepeat properties in css.

Flex: rounded corners for dynamic created images

there a better way as this example
to create round corners for dynamic (addChild or addElement) created Images?
ok, here is a custom class http://santobay.blogspot.com/2010/04/rounded-corner-image-in-flex.html . save this code as com/RoundedImage.as , create new mxml file with this code
<mx:Application name="Image_mask_test"
xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:custom="com.*"
layout="vertical"
verticalAlign="middle"
backgroundColor="white">
<mx:HBox id="hbox" width="100%">
<custom:RoundedImage source="images/test.jpg" width="250" height="250" cornerRadius="15"/>
</mx:HBox></mx:Application>
and compile. For create images dynamic use this code:
<fx:Script>
<![CDATA[
import com.RoundedImage;
public function createImage():void {
var newImage:RoundedImage = new RoundedImage();
newImage.source = "images/test.jpg";
newImage.cornerRadius = 20;
hbox.addChild(newImage);
}
]]>
</fx:Script>
No, you must use a mask, if you add it dynamically.
However, you could add a 'frame' on top of the image, if the background is solid, you can use this trick.

Simulate includeInLayout=false in pure Actionscript code

If you know Flex, you probably know what the property "includeInLayout" does. If not, this property make the parent of your component disregard the bounds (like width and height) of your component in render their own bounds.
Description in reference below:
Specifies whether this component is
included in the layout of the parent
container. If true, the object is
included in its parent container's
layout and is sized and positioned by
its parent container as per its layout
rules. If false, the object size and
position are not affected by its
parent container's layout.
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/mx/core/UIComponent.html#includeInLayout
In Flex, for example:
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="absolute"
creationComplete="application1_creationCompleteHandler(event)">
<mx:Script>
<![CDATA[
import mx.events.FlexEvent;
protected function application1_creationCompleteHandler( event:FlexEvent ):void
{
trace( container.width, container.height ); // output: 200 200
}
]]>
</mx:Script>
<mx:Canvas id="container">
<mx:Button label="Test"
width="100"
height="100" />
<mx:Button label="Test2"
width="200"
height="200" />
</mx:Canvas>
</mx:Application>
Now if I set includeInLayout="false" in second button:
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="absolute"
creationComplete="application1_creationCompleteHandler(event)">
<mx:Script>
<![CDATA[
import mx.events.FlexEvent;
protected function application1_creationCompleteHandler( event:FlexEvent ):void
{
trace( container.width, container.height ); // output: 100 100
}
]]>
</mx:Script>
<mx:Canvas id="container">
<mx:Button label="Test"
width="100"
height="100" />
<mx:Button label="Test2"
width="200"
height="200"
includeInLayout="false" />
</mx:Canvas>
</mx:Application>
I know of all framework architecture involved to implement this property and know than this property is a property from Flex Framework. What I wanna is this behavior in pure actionscript. For example:
import flash.display.Shape;
var myBox:Shape = new Shape();
myBox.graphics.beginFill(0xFF0000);
myBox.graphics.drawRect(0, 0, 100, 100);
myBox.graphics.endFill();
addChild(myBox);
trace(width, height); // output: 100 100
var myAnotherBox:Shape = new Shape();
myAnotherBox.graphics.beginFill(0xFF00FF, .5);
myAnotherBox.graphics.drawRect(0, 0, 200, 200);
myAnotherBox.graphics.endFill();
addChild(myAnotherBox);
trace(width, height); // output: 200 200
Is there some equivalent implementation in pure Actionscript to reproduce this behavior on "myAnotherBox"?
I already tried:
Change transform matrix;
Change transform pixelBounds;
Change scrollRect;
Apply masks;
And no successful.
Cheers...
You are trying to compare to different things.
In the first example, the width and height are from the UIComponent class, which actually represents a "measured" value, as provided by the Flex Framework.
In the second case, the width and height are the actual size of the rendered shape, as provided by the Flash Player.
If you open the UIComponent's implementation, you will notice that it is actually hiding the original meaning of width and height into $width and $height and provide their own implementation to it.
So to answer your question, you cannot achieve what you want working directly with Shapes (pure Flash components)
Every time you draw something in a graphics context, the width and height will update accordingly.
You options:
draw the first one in one graphics, and the second one in another graphics and measure only the first shape
compute the width and height yourself. This is what actually the containers do, and just skip the includeInLayout=false child components.
If you look up in the UIComponent source code, you'll find, that flag includeInLayout is used in invalidation mechanism (exatcly in size invalidation). If includeInLayout of the component is false, then its parent's size and its size is not recalculated.
Invalidation is native flex framework mechanism, which does not exist in pure AS projects.
You need to override width and height in your container:
override public function get width() : Number {
// place your code here
return 100;
}
override public function get height() : Number {
// place your code here
return 100;
}

Flex image component not canvas container when added to canvas

I am adding a flex image component to a mx:canvas component with a fairly large image. I have the horizontal and vertical scroll policies set to "on", but when I add the image to the canvas, it doesn't expand to show the whole image (the scrollbars aren't activated).
Anybody else have this issue.
The code is pretty straightforward:
<mx:Canvas id="myCanvas" minWidth="0" minHeight="0" horizontalScrollPolicy="on" verticalScrollPolicy="on">
</mx:Canvas>
and the script adding the image
var newImg:Image = new Image();
newImg.source = $value.sourceImg;
newImg.x = $value.positionX;
newImg.y = $value.positionY;
newImg.scaleX = $value.scaleX * _scaleRatio ;
newImg.scaleY = $value.scaleY * _scaleRatio;
newImg.rotation = $value.rotation;
myCanvas.addChild(newImg);
Ok, So I had to use clipCOntent = true. I had clipContent="false", I thought the meant that it would clip the image and anything outside the bounds could just be scrolled, buut it actually just clips it and doesn't offer a scroll.
It would be helpful if you posted your code, but without seeing it I would recommend setting minWidth="0" on the canvas. This is an old trick to force a re-measure of the canvas so it shows the scroll bars properly. Hope that helps.
Try using canvas.rawChildren.addChild(img) instead of canvas.addChild(img). That's worked for me before, otherwise you'll need to hook into the Flex component measuring system - but this is very seldomly necessary.
Cheers
Create a first canvas (viewCanvas) and place another canvas inside it (imageCanvas).
Set the scroll policies on the imageCanvas to 'off'. This should work, and the viewCanvas should have scrollbars. Note that no width/height are specified on the imageCanvas or image in code below
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:Canvas id="viewCanvas" x="95" y="65" width="169" height="159">
<mx:Canvas id="imageCanvas" x="0" y="0" horizontalScrollPolicy="off" verticalScrollPolicy="off">
<mx:Image x="0" y="0">
<mx:source>http://www.beach-holiday.cn/beach-holiday/pics/2009/09/florida-fort-lauderdale.jpg</mx:source>
</mx:Image>
</mx:Canvas>
</mx:Canvas>
</mx:Application>

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