UI delegate for a custom component

Hello folks,
I am trying to write (as said in the subject) a UI delegate for a custom component. I found the following in a Java FAQ (http://www.mindspring.com/~scdrye/java/faq.html#plaf_delegate):
8.3. How do I create a UI delegate for my custom component?
Have your component extend from JComponent (or a descendant of JComponent). Create a subclass of ComponentUI for your custom component, overriding at least the createUI() and paint() methods. To enable the new UI, override four methods of your JComponent subclass:
public class MyComponent extends JComponent {
public void updateUI() {
setUI((MyComponentUI)UIManager.getUI(this));
public void setUI(MyComponent newUI) {
super.setUI(newUI);
public MyComponentUI getUI() {
return (MyComponentUI)ui;
public String getUIClassID() {
return "MyComponentUI";
Well, it turns out that this is not enough. I also had to add during application start (just before initComponents()) the following:
UIManager.put(uiClassID, uiClassName);
to avoid exceptions during start of the program.
Well, now my component is painted (paintComponent()) is called, but the paint() method in my new UI delegate class is not called when the application starts.
It just gets called when I explicitily (in this case, using a menu item) change the L&F of the application.
If this informatio is not enough, I can add some excerpts of my code for the ease of understanding!!
Thanks a lot!

If I code a new custom component (extending JComponent, or extending the UI delegate of a standard component) and pretend it to be laf aware then I must create the corresponding UI delegate for each laf, like it happens to be with standard swing components. But I'm not sure it is feasible to create the UI delegates for all unknown existing custom lafs.You are right, this is never going to work. I suggest if you want to make your custom component look & feel aware, you design the way it displays around the l & f of other components that are part of j2se and have l&f implementations.
http://download.oracle.com/javase/7/docs/api/javax/swing/plaf/ComponentUI.html
There are instructions here:
http://download.oracle.com/javase/7/docs/api/javax/swing/LookAndFeel.html
>
On the other side, if I create a custom laf then I will also create a custom UI delegate for each standard component, but I can not create UI delegate for all unknown existing custom components.
The point here is that standard components and standard lafs are universally known, while custom components (or custom ui delegates) and custom lafs are not.
So the question is: How does a swing developer deal with the case of a new custom component that will be used in an unknown custom laf?
For instance:
1. Custom text UI delegate for dealing with styled documents in JTextField. See {thread:id=2284487}.
2. JTabbedPane with custom UI delegate that paints no tab if the component only contains one tab.
In both cases I need a UI delegate for each known laf, but what happens if the application is using a laf that certainly will not be aware of this custom functionally?
Thank you!

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Decode function not called for a custom component

I know this problem happened in the past - in the EA2, EA4 and I believe the beta version as well, but does anyone know if it has been solved for the release ?
In short - I'm working with the release, created a menuBar component and the decode method in the renderer is not called after I submit the page. In the past, there were rumors that this happened due to relative paths in the JSP (for js files, images, etc.).
Does anyone else have this problem ? or better , know how to solve it ?
Thanx,
Netta.

It's not that simple - The component is getting rendered, all the encode methods are called and the decode is called also , but only the first time the form is submitted.
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<t:MenuBar id="bar1" styleClass="myClass" >
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<t:Menu id="menu2" name="menu2">
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<t:MenuItem id="item2_2" name="item2_2" action="http://www.msn.com"/>
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In the response it looks like this -

<t:MenuBar id="bar2" styleClass="myClass" >
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and every time a menuItem is clicked on, the JS calls submit form.
Since the menus are rendered, I assume there's nothing wrong with the rendererType and any other renderer problem. Since the decode is called only once, I assume the right form is being submitted.
So, what can cause it to stop calling the decode ???
Could it be that becase I go directly to the page and not through the navigation rules ( I call window.open directly from the JS), it creates a problem ??
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Custom Validator for a Custom Component

I am having troubling passing values from my custom component
to my custom validator (via a model). For some reason when the
validate() function is called for the validator the value parameter
passed to the validator is not showing the value from my custom
component.
I have attached some example code to illustrate.
Here is my model:
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<root>
<mod>
<name>{myTextInput.text}</name>
<date>{myDateField.selectedDate.getTime()}</date>
<length>{myComp.getLength()}</length>
</mod>
</root>
</mx:Model>
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model (as sent to the validator) shows the correct value. When I
change the value of myComp the change is not reflected.
Is there a particular event (or something) being dispatched
in the other components to cause the model to get the new value
that I need to include in my custom component? I am pretty stuck
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Many thanks

Does myComp extend EventDispatcher (or any class which does)?
You need to flag the getLength() function as bindable and to
dispatch an event:
[Bindable('getLengthChange")]
public function getLength() : Number
// does whatever it does
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Can I define a constructor for a Custom Component?

I have a custom component which I instantiate through ActionScript. For the sake of clean code, I would like to be able to assign the variables through the constructor like any other class:
var myComp:CustomComponent = new CustomComponent(arg1, arg2, ...);
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//In Script tag//
public function CustomeComponent(arg1, arg2 ...):void { ... }
Are we not able to define constructors for Custom Components?

If this post helps, please mark it as such.
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public var foo:String;
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Before a public, protected, or private property defined by a getter or setter method.
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Icon for a Custom Component

Hi --
I am building a custom component and I have tried to create
the icon for the
component using
[IconFile("iconMaskInput.png")]
but its not working. Can someone help me out?
Rich

Hi --
I followed your instructions and updated the icon for the
movie clip inside
my FLA file that I compiled into a SWC file. However, when I
installed the
SWC file the icon did not update in the palette. Is this
because I had
already installed the component once? Or did I do something
wrong?
Thanks
Rich
"gnfontaine" <[email protected]> wrote in
message
news:fm4dqs$or1$[email protected]..
> You need to add it to the component inspector first,
then copy it into the
> same
> folder where you create the install package.
>
> 1.) Under the component definition found in the library,
click the default
> icon You will be present with a list, the last choice is
custom.
> 2.)Check the box display in components panel.
> 3.)If you are going to distribute the component using
mxp package, make
> sure a
> copy of the component is in the same folder as the mxi
file and that you
> add it
> to the files node in the mxi definition.
>
> Hope this helps
>

Dynamic visibility for a custom component

Hi everybody,
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At preview my component is visible as the checkbox is checked.
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Hi Evan,
I am developing a component which requires "Dynamic Visibility" property.
Its an Icon component where I have to bind a value for Icon. (i.e 0-30 Smiley, 31-70 dash, 71-100 Frown)
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Is it simply not possible to automate a custom component not implementing UIComponent?

If you look in the library panel, there should be an entry for your custom component - probably something like CustomComponent1.mxml. Drag this out onto the artboard to create a new instance of the component.
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We are working on making this sort of thing easier in the future, so stay tuned

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Hi,
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spaceMediaDisplayObject smdo = new spaceMediaDisplayObject(toDisplay);
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If it's null then you need to set the size of each component explicitly:
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Component customComponent = new CustomComponent();
panel.add(customComponent);
customComponent.setBounds(0, 0, 100, 100); // For exampleA simple layout manager could be used to make the component fill the panel, for example:
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panel.add(new CustomComponent());Hope this helps.

How do I tie a custom-component to a class?

In flash there's this great way of seperating code from
content: In the properties menu of a movieclip in your library, you
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class MyMovieClip extends MovieClip{
//etc..
so I'd have all the code that manages my movies nicely tucked
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it.
So I was wondering if you can do a similar thing in Flex. I
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file, I actually want to inherit the Application class. Similarly,
I'd like to inherit the Canvas class, yet have the nice gui for
dragging all the visuall elements in place. Is there a way?
Regard, and thanks in advance,
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If you look in the library panel, there should be an entry for your custom component - probably something like CustomComponent1.mxml. Drag this out onto the artboard to create a new instance of the component.
In the case of a custom component, you can't change much on the second instance. If you have something like a text input skin though, you can change the text it is displaying for each instance.
We are working on making this sort of thing easier in the future, so stay tuned

How do I reuse a custom component in Flash Catalyst?

All-
I'm sure this is easy, I simply can't figure it out. I've created a custom component in Flash Catalyst with two states, open and closed. I'd like to reuse this component in my app with different text assest. How is this done? Duplicating the component isn't available in this version...do I need to recreate the whole thing with different text?
Cheers,
`me

If you look in the library panel, there should be an entry for your custom component - probably something like CustomComponent1.mxml. Drag this out onto the artboard to create a new instance of the component.
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We are working on making this sort of thing easier in the future, so stay tuned

Actionscript in a Custom Component

Can anyone tell me if you can put actionscript inside of a
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<mx:Canvas
xmlns:mx="
http://www.adobe.com/2006/mxml"
height="320"
width="400"
verticalScrollPolicy="off"
horizontalScrollPolicy="off"
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just insert the script tags in the custom component and place
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<mx:Script>
<![CDATA[
// actionscript goes here
]]>
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Hi everybody!
I am trying to deploy an applet which contains a Custom Component using CREF as simulator. That means I run CREF to be waiting for incoming APDUs. By means of apdutool I run the script which contains the APDUs for the deployment of the applet. The whole CAP file is deployed properly until the custom component is tried to be deployed. Then I receive the status word 0x6424.
That means, according to the specification:
Exception occurred.
* Cause: General purpose error in the installer or applet code.
* Solution: Check your applet code for errors.
The applet works properly without the custom component, so the problem is not in the applet code.
The line of the script which fails is the following (where 10 is the tag chosen for the custom component): 0x80 0xB2 0x10 0x00 0x00 0x7F;
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So, I was wondering if someone had the same problem. Or if someone knows if CREF does not accept custom components.
Thanks in advance, I don't reach to find where the error is. May be I am missing something...
Best regards,
E_L

I would be surprised if CREF supports custom components. It would know how to use them so it would not make any sense. What is it that your custom component does?
Cheers,
Shane

How to handle children of custom component

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</x:mycomponent>
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I have tried it and managed to get the correct html-result. But I do not get the input of the checkbox if the above code snippet is a part of a html-form.
So what I realy like to have is the sourcecode of some kind of UIComponent which does something like this.
Kind Regards,
Tobias

Thanks for the swift reply Craig
My custom component has 3 elements hence the currentTarget
could be either the folder icon, the status icon or the text field.
Is there some way of finding the parent of which ever of
these sub items of the cusom component is clicked?
Here is the code for my custom component
<?xml version="1.0" encoding="utf-8"?>
<mx:Canvas xmlns:mx="
http://www.adobe.com/2006/mxml"
width="240" height="60" cornerRadius="15" borderStyle="none"
backgroundColor="#ffffff" themeColor="#ff0000">
<mx:Script>
<![CDATA[
[Bindable]
public var studentName:String ="Student Name";
]]>
</mx:Script>
<mx:Text x="64" y="24" text="{studentName}" />
<mx:SWFLoader x="10" y="10" width="32" height="24"
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<mx:SWFLoader x="19" y="42" width="11" height="11"
source="@Embed('assets/cfStatusIcon.swf')" />
</mx:Canvas>

Custom Component or Other solution to this problem...

Hello,
In my pages I have a wizard type menu consisting of:
[ prev   curr-title    next ]
The code to build this menu looks like so:
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(2) ...it possible to wrap this code in a jsp tag and pass in the messages binding string as a parameter...I have tried this before but sadly passing #{...} into a tag throws up errors.
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JC.

Create a custom component. You may define your own attributes to pass the parameters.
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Importing a custom component from Flash Catalyst with Assets

I am experimenting with Flash Catalyst to see if it would work well for us to create components for Flash Builder to use. As a test I created a very simple component with a Pie Chart and a button and exported it as a fxpl file. In Flash Builder I created a Flex library project and imported the component to it. When I tried to use the component in a trivial test app it gave me an error, saying 'Could not resolve <graphics:fc_pie> to a component implementation', presumably because it had not put the component files in the right place of the library tree - by default they were put in a folder at the same level as components but with the name of the component, below which it had a components folder and an assets folder. If I move the files in these folders to the corresponding folders under src then it works fine.
The question is, how do I get Flash Builder to do this correctly? I assume I'm missing something obvious but I am a real Flash Builder Novice and this process is about evaluating which tools to use. Sorry if I'm being a numpty. I'm using Flash builder 4.5 and Flash Catalyst CS5.5.
Any help much appreciated.

If you look in the library panel, there should be an entry for your custom component - probably something like CustomComponent1.mxml. Drag this out onto the artboard to create a new instance of the component.
In the case of a custom component, you can't change much on the second instance. If you have something like a text input skin though, you can change the text it is displaying for each instance.
We are working on making this sort of thing easier in the future, so stay tuned

UI delegate for a custom component

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