[TIMOB-1768] Android: KS alerts are not respecting opacity.

Here's a sample app.js that shows the problem (so you don't have to build KS):

   /*global Ti, Titanium, alert, JSON */
   Titanium.UI.setBackgroundColor('#000');
   var win = Titanium.UI.createWindow({  
       title:'Test',
       backgroundColor:'#fff',
       fullscreen: true,
       exitOnClose: true
   });
   
   
   var messageView = Titanium.UI.createView({
       top: 0,
       height:30,
       width:250,
       borderRadius:10,
       backgroundColor:'blue',
       opacity:0.7,
       touchEnabled:false
   });
   win.add(messageView);
   
   var v = Titanium.UI.createView({
       top: 50,
       height:30,
       width:250,
       borderRadius:10,
       backgroundColor:'blue',
       touchEnabled:false
   });
   win.add(v);
   win.open();
   

The top view -- which sets opacity -- should look different than the bottom view, which is otherwise the same. Because of this bug, they look identical.

What's happening is that because a border property is being set in addition to background, a TiBackgroundDrawable is being used. TiBackgroundDrawable maintains its own copy of a drawable which it draws to the canvas. It doesn't respect any of the alpha stuff being done in TiUIHelper.setDrawableOpacity.

I can get it to work properly by...

• Overriding setAlpha() in TiBackgroundDrawable and keeping track of the alpha value internally there, then setting it in the internal "background" variable (a drawable) before it draws to canvas.

• In http://github.com/appcelerator/titanium_mobile/blob/master/android/titanium/src/org/appcelerator/titanium/util/TiUIHelper.java#L599"> TiUIHelper.setDrawableOpacity, change ...

   if (drawable instanceof ColorDrawable) {
        ColorDrawable colorDrawable = (ColorDrawable) drawable;
        colorDrawable.setAlpha(Math.round(opacity * 255));
   ....
   

... to ...

   if (drawable instanceof ColorDrawable || drawable instanceof TiBackgroundDrawable) {
        drawable.setAlpha(Math.round(opacity * 255));
   ....
   

This means, however, that TiBackgroundDrawable doesn't get the color matrix / color filter stuff -- .setColorFilter() is not called on it. I tried overriding .setColorFilter in TiBackgroundDrawable and passing the value to its private 'background' Drawable, but that didn't work at all. Are we sure the color filter / color matrix thing works?

I haven't committed these changes, as I'm not strong in this area of drawables, color filters, etc. If Don/Marshall wants me to, I can.

here's a diff patch (based on master) in case you wanna use it.

(from [df00caa5c7758796ef957e3b58eb3b742e271e4a]) merging Bill's original patch for fixing opacity on views with custom background drawables. tested with [#2031] as well to verify [#1768 state:fixed-in-qa] https://github.com/appcelerator/titanium_mobile/commit/df00caa5c7758796ef957e3b58eb3b742e271e4a"> https://github.com/appcelerator/titanium_mobile/commit/df00caa5c775...

Failed in 1.6 and 2.1, seems to work fore createImageView, but not createView.
Titanium SDK version: 1.5.0 (11/22/10 20:42 19a59fd)

used the test code above

passed Android 2.1 Titanium SDK version: 1.5.0 (11/24/10 12:05 c0aff27)
passed Android 1.6 Titanium SDK version: 1.5.0 (11/24/10 12:05 c0aff27)