Hopefully this quick post will be a bit of a time saver for Flex Developers developing Flex 4 SDK projects with Flash Builder or other tools…
Over the last year or 2 I’ve really got comfortable with reskinning Flex 3 applications. For me the quickest, simlest way has usually been to cut up the designer’s photoshop file and implement Scale 9 and syntax in my Flex css files – an example of a recent Flex 3 button skin looked like this:
.answerButton
{
fontSize : 44px;
fontWeight : bold;
paddingLeft : 15px;
paddingRight: 15px;upSkin : Embed(source=”assets/images/new/buttons/answerButtonUp.png”,scaleGridTop=”20″, scaleGridLeft=”19″, scaleGridRight=”145″, scaleGridBottom=”99″);
overSkin : Embed(source=”assets/images/new/buttons/answerButtonOver.png”,scaleGridTop=”20″, scaleGridLeft=”19″, scaleGridRight=”145″, scaleGridBottom=”99″);
downSkin : Embed(source=”assets/images/new/buttons/answerButtonOver.png”,scaleGridTop=”20″, scaleGridLeft=”19″, scaleGridRight=”145″, scaleGridBottom=”99″);
disabledSkin: Embed(source=”assets/images/new/buttons/answerButtonUp.png”,scaleGridTop=”20″, scaleGridLeft=”19″, scaleGridRight=”145″, scaleGridBottom=”99″);
selectedDisabledSkin: Embed(source=”assets/images/new/buttons/answerButtonUp.png”,scaleGridTop=”20″, scaleGridLeft=”19″, scaleGridRight=”145″, scaleGridBottom=”99″);}
Luckily for me the Flex 4 SDK is backwards compatible for the most part so you can still skin an mx.controls.Button component with the CSS above.
However… one of the reasons I’ve been migrating my Flex 3 project to Flex 4 is to make use of some of the skinning improvements it offers with it’s new Spark components built on top of the Flex 3 halo components.
The code above does not work on a spark.components.Button. I assumed it would… Here’s how I got the example below to work:
http://www.nickkuh.com/demos/gumbo/scale_nine/
Step 1) Create a new Flex Project in Flash Builder
Step 2) You can still customize the label colours and states but you’ll need to implement the new namespaces in CSS introduced in Flex 4 to avoid warnings and errors – see the gumbo_scale_nine.css file.
Step 3) You’ll also notice within the gumbo_scale_nine.css file that I’m pointing a custom style (‘answerButton’) to an MXML skin file in the location com.nickkuh.skins.AnswerButtonSkin.mxml. This is the file that I’ve used to custom skin the spark button component. I copied the ButtonSkin.mxml file that comes with Flex 4, stipped out a load of fills and strokes I didn’t require and add these important lines:
<s:BitmapImage left=”0″ right=”0″ top=”0″ bottom=”0″ source=”@Embed(source=’assets/answerButtonUp.png’,scaleGridTop=’20′, scaleGridLeft=’19′, scaleGridRight=’145′, scaleGridBottom=’99′)” resizeMode=”scale” includeIn=”up” />
<s:BitmapImage left=”0″ right=”0″ top=”0″ bottom=”0″ source=”@Embed(source=’assets/answerButtonOver.png’,scaleGridTop=’20′, scaleGridLeft=’19′, scaleGridRight=’145′, scaleGridBottom=’99′)” resizeMode=”scale” excludeFrom=”up” />
By default the resizeMode parameter will just tile and repeat your graphic which wasn’t the desired functionality.
So that’s it. Although it took more step to reskin than a Flex 3 component I can certainly see the benefits of the separate FXG skin file. Next step is to change that SimpleText labelElement into a RichEditableText component and enable multilines and imline images into my Spark buttons. Wish me luck!
Get Lippy! is a fun entertainment Application that I built for the iPhone earlier this year (2009).
This silly iPhone App automatically records when users talk into the microphone. Then it trims the sound input and plays back the speech either like a Chipmonk or Barry White: the App enables you to control the pitch adjustment.
You can choose pictures from your iPhone library or take your own on the fly and then select from 4 comic talking mouths that you can resize/reposition to overlay your photos. When the app plays back a recording it animates the lips fast or slow depending on the pitch as it detects audio levels.
New functionality in version 1.1 includes the ability for users to submit their animated recordings to the Get Lippy Gallery and send them to their mates.
Download Get Lippy! from the App Store
Update (4th October 09): Recently I was chosen as one of the 3 minute wonders to speak at Flash on the Beach ’09 conference. My presentation was about the iPhone Development Workflow from a Flash Developer’s perspective. You can see the video and a few more details here.
It’s taken a while for me to discover the simple solution as to why one of my 2 UITouch objects when grabbing the allTouches set from the iPhone SDK touchesMoved event always resulted in 0,0 co-ordinates in my view…
NSSet *allTouches = [event allTouches];
Solution: you need to switch on the multipleTouchEnabled property of the view you want to get multiple touch events from!! ie:
[self.view setMultipleTouchEnabled:YES];
Hope this post helps others…
The objective:
The screen grab below is taken from a Flex application I’m building. This page of the app comprises of 2 VBoxes inside an HBox. The 2 VBoxes need to size to 100% of the height of the HBox container. The user can edit any of the text fields. When the user edits the body text of the left column, if they use up all the vertical space of that left VBox then I’d like the VBox containing the title and the boy text to create scroll bars, not to resize it’s parent VBox. Simple right?
Not so simple… Here’s a snippet of the code:
<mx:VBox width=”50%” height=”100%” styleName=”whiteContainer”>
<mx:Box direction=”vertical” width=”100%” height=”100%” styleName=”scrollableContentWithText” >
<mx:HBox width=”100%” verticalAlign=”middle”>
<mx:Image source=”assets/images/book74x42.png” width=”74″ height=”42″ />
<controls:AdvancedTextArea id=”title1″ multiline=”false” textModify=”captialize” styleName=”whiteContainerHeader” condenseWhite=”true” width=”100%” prompt=”{resourceManager.getString(‘resources’,'ENTER_TEXT_PROMPT’).toUpperCase()}” />
</mx:HBox>
<controls:AdvancedTextArea id=”body1″ styleName=”blueOnWhiteText” condenseWhite=”true” width=”100%” prompt=”{resourceManager.getString(‘resources’,'ENTER_TEXT_PROMPT’)}” />
</mx:Box>
</mx:VBox>
And here are the results when that body text gets too deep for the VBox:
So the whole parent HBox ended up getting stretched. Not the results I expected.
The solution as it turns out is pretty straight forward. The VBox containing the left column needs it’s minHeight and minWidth properties set to 0! The reason is that with containers using percentage based sizing flex sets the min height and min width properties to the cumulative width and height of the container’s children components. So in my example as the editable text component gets deeper/taller this automatically increases the minHeight property of it’s parent container.
So by explicitly setting the parent container’s minHeight and minWidth to 0:
<mx:VBox width=”50%” height=”100%” styleName=”whiteContainer”>
<mx:Box direction=”vertical” width=”100%” height=”100%” minHeight=”0″ minWidth=”0″ styleName=”scrollableContentWithText” >
<mx:HBox width=”100%” verticalAlign=”middle”>
<mx:Image source=”assets/images/book74x42.png” width=”74″ height=”42″ />
<controls:AdvancedTextArea id=”title1″ multiline=”false” textModify=”captialize” styleName=”whiteContainerHeader” condenseWhite=”true” width=”100%” prompt=”{resourceManager.getString(‘resources’,'ENTER_TEXT_PROMPT’).toUpperCase()}” />
</mx:HBox>
<controls:AdvancedTextArea id=”body1″ styleName=”blueOnWhiteText” condenseWhite=”true” width=”100%” prompt=”{resourceManager.getString(‘resources’,'ENTER_TEXT_PROMPT’)}” />
</mx:Box>
</mx:VBox>
… I ended up with the desired result:
There are a number of useful Flex techniques I use in the Flex Apps I develop all the time and I thought that some of these might be useful for others. So here’s the first… How to replace that nasty default Flex preloader with your own Flash animated version. Here’s the result (I just downloaded a free preloader animation from the web and applied it to this tutorial:
http://www.nickkuh.com/demos/custom_preloader/
Flex source files can be downloaded from here:
http://www.nickkuh.com/demos/custom_preloader/srcview/CustomPreloader.zip
How it works:
Inside the main application MXML you can specify a custom preloader class for your application to use:
<mx:Application xmlns:mx=”http://www.adobe.com/2006/mxml”
layout=”vertical”
backgroundColor=”#000000″
backgroundGradientAlphas=”[0.0,0.0]“
paddingTop=”30″
applicationComplete=”init()”
preloader=”com.nickkuh.preload.Preloader” viewSourceURL=”srcview/index.html”>
So you’ll see I’m pointing the preloader to my com.nickkuh.preload.Preloader class. This class extends the default Flex DownloadProgressBar class: mx.preloaders.DownloadProgressBar. The Flex Framework passes the application it’s loading to preloader setter method which I’m overriding:
override public function set preloader(value:Sprite):void{
value.addEventListener(ProgressEvent.PROGRESS, progressEventHandler, false, 0, true);
value.addEventListener(Event.COMPLETE, completeEventHandler, false, 0, true);
value.addEventListener(FlexEvent.INIT_PROGRESS, initProgressEventHandler, false, 0, true);
value.addEventListener(FlexEvent.INIT_COMPLETE, initCompleteEventHandler, false, 0, true);
}
So my custom Preloader class is now able to listen to the application preloading events – halfway there…
In the constructor for the Preloader class I’m creating an instance of another custom class which deals with displaying the Flash loading animation and adding this instance to the stage:
progressBar = new ProgressBar;
this.addChild(progressBar);
The Preloader class listens to the instance of the com.nickkuh.preload.ProgressBar class for the custom event ProgressBar.FADE_OUT_COMPLETE. Only when that event is fired will the Preloader class in turn fire an Event.COMPLETE event which the Flex app listens for before it displays the loaded application and fires the applicationComplete event. So this set-up enables the custom ProgressBar to control when the Flex app changes the view from preloader to application.
The custom ProgressBar class extends Flex’s Loader class and loads in the flash loading animation. I’ve set this up so that the ProgressBar checks for the path to the preloader.swf via FlashVars:
var url:String;
if (this.stage.loaderInfo.parameters.hasOwnProperty(“preloaderURL”))
{
url = this.stage.loaderInfo.parameters.preloaderURL;
}
else
{
url = “preloader.swf”;
}
var urlRequest:URLRequest = new URLRequest(url)
this.load(urlRequest);
You’ll find the fla for the preloader in the source files in a folder called ‘design’. The fla actually includes a couple of methods on frame one:
stop();
function setProgress(n:Number)
{}
function set ready(b:Boolean)
{
if (b) gotoAndPlay(2);
}
The custom ProgressBar class calls these methods with progress updates and sets the ready setter to true when the Flex App has finished loading. If you’re loading animation is a progress bar or needs to give percentage feedback then you can customise the setProgress(n:Number) function – n will be between 0 and 1 – 1 for fully loaded.
In my fla once the preload completes it then plays a few more frames before fading out. This animation could be changed to you requirements.
Once the internal fade out complete the fla fires off an “animationComplete” event which the ProgressBar is listening out for. At this point the closeScreen method of ProgressBar handles the event and ProgressBar fades itself out. Once complete it in turn fires the FADE_OUT_COMPLETE event which causes the main Flex app to close the preloader and display your Flex App.
Yes, it’s a bit time consuming to make a simple preloader but I now use this set-up over and over again. Feel free to do the same!