Here is a small spinning wheel example on how to do this with an old style ASCII spinning wheel animation. Enter the LabelProgressIndicator.mxml component:

<?xml version="1.0" ?>
<mx:HBox xmlns:mx="http://www.adobe.com/2006/mxml">
    <mx:Script><![CDATA[
        [Bindable]
        private var statusText:String;

        [Bindable]
        private var progressText:String;

        private const SPIN_CHARS:String = "/-\\|/-\\|";

        private var workingDotsTimer:Timer;
        private var progressCounter:int;

        public function startProgress(status:String):void {
            if (workingDotsTimer == null) {
                statusText = status;
                workingDotsTimer = new Timer(200);
                progressCounter = 0;
                workingDotsTimer.addEventListener(TimerEvent.TIMER, onWorkingDotsTimer);
                workingDotsTimer.start();
            }
        }

        public function stopProgress():void {
            if (workingDotsTimer != null) {
                workingDotsTimer.removeEventListener(TimerEvent.TIMER, onWorkingDotsTimer);
                workingDotsTimer.stop();
                workingDotsTimer = null;
                statusText = null;
                progressText = null;
            }
        }

        private function onWorkingDotsTimer(event:TimerEvent):void {
            if (progressCounter == SPIN_CHARS.length - 1) {
                progressCounter = 0;
            } else {
                progressCounter++;
            }
            progressText = SPIN_CHARS.charAt(progressCounter);
        }

        ]]></mx:Script>

    <mx:Label id="status" text="{statusText}"/>
    <mx:Label id="progress" text="{progressText}" fontFamily="courier" fontWeight="bold"/>
</mx:HBox>

and here is how to use it:

<?xml version="1.0"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:ui="*">

    <mx:Button click="progress.startProgress('working')" label="Start"/>
    <mx:Button click="progress.stopProgress()" label="Stop"/>

    <ui:LabelProgressIndicator id="progress" />

</mx:Application>

Vanilla Example

Here is a dead simple vanilla sample of flex that does a little bit of data binding:

<?xml version="1.0" ?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
    <mx:Script><![CDATA[
        [Bindable] public var value: String = "blah";
    ]]></mx:Script>

    <mx:TextInput id="textInput" text="{value}"/>
</mx:Application>

where value is bound into textInput.text will generate quite a bit of supporting code, when being mxmlc’ed. Basically, it seems like flex operates with two concepts behind the scenes: Bindings and Watchers.

Bindings

A Binding is a one-way connection, that can read a value from a source and set it on a destination, but only when explicitly executed. There is not listening for changes built into a binding as such, it is just a mechanism that can be executed by someone, to transfer a value between a source and a destination.

So, how does a binding get executed? It does so, when the Watchers it is connected to fires. A binding acts as listener for watcherFired on a Watcher, which is how it gets executed when changes happen.

Here is the binding setup, that flex generates for the above example:

        binding = new mx.binding.Binding(this,
            function():String {
                var result:* = (value);
                var stringResult:String = (result == undefined ? null : String(result));
                return stringResult;
            },
            function(_sourceFunctionReturnValue:String):void {
                textInput.text = _sourceFunctionReturnValue;
            },
            "textInput.text");

basically, it instantiates a mx.binding.Binding with the parameters:

• this which is this context – pun intended – means the FlexTest application class
• a function that can read the source value when executed
• a function that can set the target property when executed
• a textual string of the target (docs says it is used for validation)

this sets up a “channel” from source to target.

Watchers

While Bindings only implement the reading of the source and setting into target, the other big part of flex data bindings is actually determining if and when, a binding should execute. This is where Watchers come in.

A Watcher can watch for changes on something, one typical example is a change of a property value. When such a change is detected, the watcher notifies its listeners (which are Binding instances) about the change. It is then up to the listener (the bindings), to actually read out the source and set the target (aka: Execute the binding). It is the Watcher, that determines if a value has actually changed.

Here is the watcher setup, that flex generates for the above example:

        watchers[0] = new mx.binding.PropertyWatcher("value",
            { propertyChange: true },
            [ bindings[0] ],
            propertyGetter);

as you can see, it instantiates a mx.binding.PropertyWatcher instance, as it is a property we are binding from, with the following parameters:

• a map of event names as keys, that are the event to listen for, when watching changes. This is what can be overridden with [Bindable("otherEventNameHere"])
• an array of listeners, that get called on their watcherFired method when the watcher detects a change (the listeners are Binding instances, and in this context bindings[0] is the exact binding that we saw the code for just before
• and lastly propertyGetter is a method, that can return access to properties in the context watched

I am sure you can image how this works then. By hey, … when is the “propertyChange” event being dispatched in our code. I mean, when you look at the initial example code, if I was to assign a new value to the value property, there sure ain’t any code there, which fires any events.

Well, it turns out mxmlc has generated code for that too:

    [Bindable(event="propertyChange")]
    public function get value():String {
        return this._111972721value;
    }

    public function set value(value:String):void {
    	var oldValue:Object = this._111972721value;
        if (oldValue !== value) {
            this._111972721value = value;
            this.dispatchEvent(mx.events.PropertyChangeEvent.createUpdateEvent(this, "value", oldValue, value));
        }
    }

it simply moves the original value property to a generated name _111972721value and adds a get/set pair on the value name instead. Clever. And hey, look into that setter. It dispatches the propertyChange event, when changed.

This is what the script does:

• Ask the user for an input folder and an output folder
• Ask the user for which ratio he wants to check against (e.g. 1.5 if you want a 2:3 ratio)
• Run throug all image files in the input folder, check if the ratio is the requested, and if not, moves files to output folder

All I have to do then, is to crop the files moved to the output folder, to my requested ratio. Actually, the “Image Events” library that I use to check dimensions can also crop, but it does so from the center. I want to control what is cropped myself.

And respect to Apple for giving us such an easy to use yet still powerful tool like AppleScript. I used the AppleScript Editor to write the script, and then noticed how I could just save it as an application. Cool!
Here’s the script:

-- ask for input folder containing images
set theInputFolder to (choose folder with prompt "Pick the folder containing the images to check ratio against") as string

-- ask for output folder to move files that does not fulfill ratio
set theOutputFolder to (choose folder with prompt "Move image files not fulfilling ratio where?" without multiple selections allowed and invisibles) as string

-- check folders are not the same
if theInputFolder is equal to theOutputFolder then
	error "Input and output folder may not be the same" number 500
end if

-- ask user for the ratio
display dialog "Enter image ratio" default answer "1.5"
set theRatio to text returned of result as real

tell application "System Events"
	set theImageFiles to every file of folder theInputFolder whose name does not start with "." and (file type is "TIFF" or file type is "JPEG" or name extension is "tiff" or name extension is "tif" or name extension is "jpeg" or name extension is "jpg")
end tell

repeat with i from 1 to the count of theImageFiles
	set theImgFile to (item i of theImageFiles as alias)
	tell application "Image Events"
		set theImg to open theImgFile
		set theDimensions to dimensions of theImg
		set theWidth to item 1 of theDimensions
		set theHeight to item 2 of theDimensions
		set min to theHeight
		set max to theWidth
		if (theWidth < theHeight) then
			set min to theWidth
			set max to theHeight
		end if
		close theImg
	end tell

	-- a little rounding
	set theImgRatio to (((max / min) * 10) as integer) / 10

	if (theImgRatio is not equal to theRatio) then
		tell application "Finder"
			move theImgFile to theOutputFolder
		end tell
	end if
end repeat

display dialog "Done" buttons {"OK"} default button 1

Sparks Creativity

Well, that one was kind of obvious, as that was one of the main reasons I started doing it. Nevertheless, it is pretty important.

Okay, I could have gone for a 365 days challenge, but that just seemed too much for me. Anyways, faced with the task of doing 30 self portraits in a row, one has to come up with some ideas. For starters, I have some myself, but what I also did (and do) was to go out there on the net, and see what others have done. Searching flickr for self portraits has proven really helpful, and sparked many ideas to new ways of doing portraits.

Force Learning of Techniques

Even though I have had a DSLR for some years now, it is only within the last copuple of months, that I bought myself a decent tripod. And even then, I haven’t taken that many shots using it yet. Going into self portraits, I am using my tripod for many of the shots. And already now, I feel much more confident using the tripod, setting it up, knowing what it can do and what it cannot, etc.

Another learning experience I am into currently, is setting up flashes. Not long ago, I bough some cheap wireless Cactus triggers and an extra cheap-o Hong-Kong flash. These are really fun to play with. More and more, I am starting to think lighting into my pictures. And that does not only go for the portaits, but for all shots. I acknowledge, that I should have done this long ago, but I haven’t.

Opportunity to Gear Up

We all know it. Photography is a gear sport and I simply had to buy a wireless remote trigger for this project. Still eagerly awaiting it though, … from Hong-Kong again.

So, if you are into photography, I can only recommend taking up a photography challenge of some sort. You can follow the results of my challenge in my flickr set here.

A restrospective in an agile process is the simple idea about “stepping back and looking at the process”. What we did, was take out 30-45 minutes, where:

1. the development team meet up
2. an outsider acts as facilitator

I like agile processes for software development, but aside from that, I do not care much for a lot of process. I like my time spent on development – designing and writing code. This is also why I liked (and was surprised that) an agile restrospective can be so short and lightweight.

In the retrospective I participated in, I acted as the facilitator. As such, I was not a part of the development team. I had some, albeit little, knowledge of what they were developing, but that turned out to matter less. In short, this is what we did:

• on the morning of the retrospective day, we agreed on time to meet later
• at that time, the team and I met up in a meeting room – pretty much blank and unprepared
• I, the facilitator, started asking questions against the process
• the team answered and discussed back and forth

The whole thing took around 30 minutes. The questions asked were stuff like:

• what went well in the last sprint?
• what did not go that well?
• what to take with us and repeat in coming sprints?
• what to do better in coming sprints?
• …

but the really nice thing is, that having a project-external facilitator proved to be really helpful in the way that:

• He (the external facilitator) will ask the questions, that lies as implicit knowledge in team members, and hence wouldn’t be touched upon. Like, when I asked “how do you do your etimates”, which led to a discussion on diffent ways to do estimation.
• The team being retrospected can get new input from the knowledge of the facilitator – and the other way around, making the facilitator take something with him too (a true win-win)
• The facilitator gets insight into how other projects in the organisation is run and what they do. This is knowledge and project-status sharing while retrospecting.

All in all, I had the fealing that this was helpful. As a consequence of this, I repeated it on a project at a client where I was part of the team, and we brought in another party as facilitator – a developer on another project, but from the same organization.

Some important rules I feel compelled to emphasize:

1. Keep the retrospective short (less than 60 min), and
2. Come largely unprepared and resist documenting the output.

Now, do not get me wrong. I think everybody should pay for what they use. I think pirates are a bad thing. But we need an open solution, that everyone are free to provide implementations of, without the need to buy specs or pay roalties for the use or implementation of a certain codec.

This is also why I think Opera and The Mozilla Foundation are doing the right thing when speaking about which video codec to choose for the open web platform. Of course, either H.264 should be patent free or everybody should team up around an open, patent free codec like Ogg Theora.

If not, consumers will pay. Less products/players to choose from. No free players or encoders. Platform locked features. Etc. For instance, currently I have no way to use the SF Anytime VOD service on my Mac, because they have choosen to tie it to the Windows Media format and player. I understand their choice, given the current availability of DRM solutions around.

If everybody would just team up on an open, patent free codec, like Theora, I am sure there would be viable DRM solutions around too. Solutions that would play on all major platforms, and not just in one specific player on one specific platform. Instead of battling patents with eachother, the major players should battle on providing the best implementation and best products with the coolest features. Stuff that would really give the users a better experience.

Nice to see JetBrains are thinking some of the same thoughts, considering we never followed through on our own idea way back.

Currently, with the IDEA8, there is some support for importing POMs that use flexmojos. With the upcoming Maia release, this integration is further enhanced.

In this blogpost, JetBrains explains how to import for POM, and there are some good pointers, that I need to remember for my next POM import. Most notably, enabling the generation of a compiler config file, to have the same settings used by IDEA as flexmojos do at compilation.

Due to serious color-related limitations on the display of my wifes laptop, she currently imports her pictures onto my Mac. In addition, my oldest child is taking more and more pictures with her camera, all of which also goes onto my Mac. To avoid “polluting” my own iPhoto library, I wanted to create and manage separate libraries.

It turns out, that if you hold down the Option-key (Alt-key) while starting iPhoto, it will popup a dialog with the options to either create a new library or choose an existing one.

Nice!

So, starting your program, application server, … with -Djaxp.debug=true enables all sorts of initialization/bootstrap debug information, that can be helpful.

I wrote the below code on Java5, thinking this was a way of validating a piece of XML against a schema definition. And indeed, it does work on Java5:

SchemaFactory sf = SchemaFactory.newInstance("http://www.w3.org/2001/XMLSchema");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setSchema(sf.newSchema(schemaUrl));
DocumentBuilder parser = dbf.newDocumentBuilder();
parser.parse(new InputSource(new CharArrayReader(xml.toCharArray())));

Only thing is, this does not validate on Java6. In fact, if I install an ErrorHandler on the DocumentBuilder that simply rethrows exceptions, the parsing will complain about the very first attribute it meets, even though the Schema allows it.

It took me a while, to figure out what to do. In the process, I debugged into both Apache and the com.sun…apache packages, to try and find out what was different with parser behaviour on Java6. In the end, it proved really simple. I just hard to learn to actually use the javax.xml.validation API instead. An API made for, … validation. Duuh! Here is the code, that works on both Java5 and Java6:

SchemaFactory sf = SchemaFactory.newInstance("http://www.w3.org/2001/XMLSchema");
Schema schema = sf.newSchema(schemaUrl);
Validator validator = schema.newValidator();
Source source = new StreamSource(new CharArrayReader(xml.toCharArray()));
validator.validate(source);

But sometimes, it would be nice to have direct access to the instance behind the proxy. In my case, it was in a test case, where I wanted to inject one dependency out of many, with a stub implementation. I am using the spring AbstractJpaTests class, which will inject proxied dependencies of beans into my testcase. All the dependencies of the injected, proxied class has also been setup by spring from the context, but I would like to set one specific of them to a stub implementation.

Problem is, the setters for dependency injection is not on the bean interface, and as such, I cannot call them on the bean instance. I also cannot cast it to the implementation class, because in my case, spring is applying the aspect using a JDK proxy, hence it is not the the implementation type, only the interface type.

Here is the code I ended up with for getting the target object:

  @SuppressWarnings({"unchecked"})
  protected <T> T getTargetObject(Object proxy, Class<T> targetClass) throws Exception {
    if (AopUtils.isJdkDynamicProxy(proxy)) {
      return (T) ((Advised)proxy).getTargetSource().getTarget();
    } else {
      return (T) proxy; // expected to be cglib proxy then, which is simply a specialized class
    }
  }

I found out (by debugger inspection), that the proxy class that spring generates implements Advised, which contains the getTargetSource() method. And on a TargetSource, one can get the actual target. I am not sure if all spring proxies always implement Advised, but it seems to do in my code

I am using the code like this:

  @Override
  protected void onSetUp() throws Exception {
    getTargetObject(fooBean, FooBeanImpl.class).setBarRepository(new MyStubBarRepository());
  }

One question: The targetClass parameter on the above getTargetObject method is not used within the method itself. But I cannot find another good way to pass the type paramter into the method. Can you?

Another question: Are there any other good ways, from a test, to inject one dependency on a spring managed bean?

When you write a groovy script, chances are that, when it gets just a little bigger than damn-small, it will require some third party dependencies, to be able to run properly. So, what do you do? You end up either a) package dependent jars in a lib folder and dist as a zip with a script that can build a classpath or, b) re-package all dependencies into one big runnable jar including both dependencies and your not so little script anymore.

But now, there’s “Grab”

@Grab(group='com.ancientprogramming.fixedformat4j', module='fixedformat4j', version='1.2.2')
class Grabber {
  Grabber() {
    println "Code that is supposed to use fixedformat4j"
  }
}
new Grabber()

The “Grabber” class above is an example of a class, which is pretending it needs fixedformat4j in its classpath. When compiled, the groovy compiler will add code to lookup and download the dependencies from some repository (maven, ivy). When run, this generated code is executed, dependencies located and downloaded (if needed), and your script is then executed with access to the downloaded classes/jars.

After trying it out, a little digging around made me discover, that the downloaded dependencies end up in $HOME/.groovy/grapes

Cool?

Through annotations, one is able to tell the compiler to change the code, before it is producing actual byte-code output from the AST. One example is the ever present Singleton “pattern”, which is implemented as an annotation, like this:

@Singleton
public class SingletonTest {
}
new SingletonTest()

When run, this code will produce an exception at runtime, like this:

Caught: java.lang.RuntimeException: Can't instantiate singleton SingletonTest. Use SingletonTest.instance
  at SingletonTest.<init>(SingletonMain.groovy)
  at SingletonMain.run(SingletonMain.groovy:4)

What happens here is, that the compiler is producing a singleton from SingletonTest, putting a property “instance” on the class, at compile-time.

I guess stuff like this are making the job even harder for IDE developers. Not only do they not get as much type information to work with as with statically typed languages, but also shall they know about meta-programming like this, that changes the code when compiled. The code above does not color red in IDEA (yet).

First thing to do was to go into iPhoto preferences “General” and set Photoshop Elements as the external editor program. Nice and easy. I then tried to open my photos in external editor and sure enough, photoshop elements opened up, … with the JPEG image

Here is the tip: You need to set the “Use RAW when using external editor” inside iPhoto preferences “Advanced”. Like this pictures shows:

Only thing I need now, is to find out how to make iPhoto notice the edits in Photoshop Elements when I come back. Anyone know how to do that?

Error starting JDBC transaction. Cause: java.sql.SQLException: Io-exeption: The Network Adapter could not establish the connection.

..turned out to lead me in the wrong direction.

I have had these kind of exceptions before, saying “The Network Adapter could not establish the connection”, and it has always been a problem of network connectivity. But this time, it was due to a driver misconfiguration. Or at least, an update of the ojdbc14.jar inside weblogic lib directory made the problem go away.

I do not know which version of ojdbc14.jar that came with my weblogic 8.1, but I dropped a v10.2.0.2.0 there, and it worked.

When using the Image component as a drop-in item renderer in a Flex DataGrid, there are things to remember or know about sizing. You can give the individual columns a width setting of their own, but the row height is a little different:

• either (a) set rowHeight of the grid, which will render all rows same height no matter the dimensions of the images…
• or, (b) set variableRowHeight to true, in which can the dimensions of the images will determine the height of each individual row

Well, just to be fair, I thought I would post a short blog entry about how things have changed.

Since then, many of the issues I and others have reported in the IDEA Feedback Jira have been solved, sometimes within hours of them being reported. Currently, I am really enjoying Flex development using IDEA, and I am doing it day in and day out.

What is really nice is, that when I am not doing Flex code, I am doing backend code for the Flex client. And that code is Java. And IDEA never left being the greatest IDE for Java development. Now, it is also great for Flex.

Sincerely, an IDEA fan boy!

So, I went into IDEA settings for keyboard bindings and found what the picture below shows:

First thing: I assume, that “Move Caret to Text End” is what I want, as in, other words for “goto file end”. Am I right?

Next thing: What the heck is that oblique arrow doing in the shortcut I looked hard but could not find it on my MacBook Pro keyboard:

I then got to looking on the external keyboard for the mac of a colleague of mine, and spotted the keys on that keyboard, like here:

Is there any way for me to emulate these keybindings on my MacBook Pro, using some kind of weird and hard to remember combination of shift, fn, ctrl, option, arrows, command key or something completely different like a secret trackpad gesture?

java.lang.NullPointerException
        at com.intellij.psi.stubs.StubTree.(StubTree.java:9)
        at com.intellij.lang.javascript.index.JSPackageIndex$2.map(JSPackageIndex.java:60)
        at com.intellij.lang.javascript.index.JSPackageIndex$2.map(JSPackageIndex.java:91)
        at com.intellij.util.indexing.MapReduceIndex.mapNew(MapReduceIndex.java:82)
        ...

and

java.lang.AssertionError
        at com.intellij.util.io.storage.Storage.deleteRecord(Storage.java:315)
        at com.intellij.openapi.vfs.newvfs.persistent.FSRecords.b(FSRecords.java:213)
        at com.intellij.openapi.vfs.newvfs.persistent.FSRecords.a(FSRecords.java:296)
        ...

In addition, one file showed in IDEA to have strange content, looking like it came from another sourcefile. Though, when i looked into the file from the console, it wasn’t changed at all.

I ended up solving this by closing down IDEA and deleting its cache files (on my Mac stored in ~Library/Caches/IntelliJIDEA8x/caches).

Starting IDEA again and opening my project, it rebuilt indices and everything seems to work again