Adobe AIR Development

[steve_web]

As any "good" developer does... I want to try and avoid hardcoding any screen size information in my AIR based apps to ensure that they can work on the PlayBook (1024x600), the BB10 FullTouch (1280x720), the BB10 w/Keyboard (720x720)... and anything else that may ever come up in the future... (even though RIM has indicated they are constraining themsleves for BB10 to the above dimensions as noted here: http://devblog.blackberry.com/2012/08/blackberry-10-screen-resolutions/ )

So in order for this to work... I need to ensure:

a.) any default configuration doesn't lock in a size...

b.) I need to be able to programatically read in the device dimensions (and know if I need to "rotate" my view)

For item (a) I've been a bit confused by the opening line I've seen in documentation for your *.as class files that starts like this...

package{
  import abc;
  ...

  [SWF(width="1024", height="600", backgroundColor="#000000", frameRate="30")]
  public class MyAppName extends Sprite{
    ...
  }
}

Although I'll be honest I haven't even tried... can I drop that metadata line? or can I change the values to variables like ${DeviceWidth}, $DeviceHeight}...? or is there a better option?

For item (b) I need to be able to read in the actual device dimensions.... (width, height) and potentially "know" how to force the rotation.

e.g. for a Game I'm making... it is intended to run in the "Landscape" orientation on the PlayBook (and on a full touch BB10 phone)... and although it really wouldn't matter... I'm guessing I'd prefer the "portrait" orientation for a BB10 keyboard phone (even though the screen resolution would be the same at any orientation.

Am I right to be looking at these values for width and height?

var width:int = qnx.display.DisplayMode.width;
var height:int = qnx.display.DisplayMode.height;

 and for orientation... this one?

var isPreferred:Boolean = qnx.display.DisplayMode.isPreferred;

Cheers,

Steve

[Ebscer]

If you are looking to force the application into Portriat or Landscape mode, you are best off doing that from the xml file instead of in code.

Also I believe that it is safe to drop the metadata line (but have to admit that I haven't tried it).

[steve_web]

Yeah I could do that... but I must confess I'm also not sure for BB10 phones with a keyboard where the screen is actually a square... is "Landscape" considered to be the phone orientation like the Bold 9900 where the device is longer in the vertical... but the screen is longer in the horizontal... OR is the BB10 devices with a keyboard the opposite... and "Landscape" is when the device is turned 90 degrees... and thus the horizontal length is longer (720+the sideways keyboard). ;-)

[jtegen]

You can drop the meta line and include this in your main constructor:

this.stage.frameRate = 30;
this.stage.align     = StageAlign.TOP_LEFT;
this.stage.scaleMode = StageScaleMode.NO_SCALE;

 The stage size is picked up from the device boundary.

In the update display function, you can compare the width and height to determine orientation.  Portrait ( w < h ) is "normal" orientation of the device.

[steve_web]

Thanks jtegen I'll check it out!

[dmalik]

Sarah Northway wrote a good article on this topic here - http://www.adobe.com/devnet/air/articles/multiple-screen-sizes.html 

Cheers,
Dustin