Setting alpha using animation library

[francoisg]

Hi All,

Is it possible to permanently set the alpha of an item to say 0.5 and then only once the user clicks on it it will become fully opaque?

I am using:

a.InitializeAlpha("a", 0.5, 0.5)
a.Duration = 0 'adjust your blinking speed
a.RepeatCount = 0
a.Start(btn)

i.e. Instead of blinking i want it to stay transparent until clicked on...

Regards
Francois

 

[Erel]

Try this library: http://www.b4x.com/forum/additional...dates/21313-lib-animationplus.html#post123188

 

[francoisg]

Hi,
thank you for the reply. Is it at all possible to create dynamically (in code) a button, set the button image to display and make it (the button, with the image) say 50% transparent?

Maybe using drawable somehow?

 

[yttrium]

Hi,
thank you for the reply. Is it at all possible to create dynamically (in code) a button, set the button image to display and make it (the button, with the image) say 50% transparent?

Maybe using drawable somehow?

This should be possible using a Statelist Drawable, which has an alpha field. Set it to 127.

 

[francoisg]

Hi,
I'm using the following code but (obviously) this does not work with bitmaps:

   Dim cd As ColorDrawable
   cd.Initialize(Colors.ARGB(127, 255, 128, 128), 5)
   Dim sld As StateListDrawable
   sld.Initialize
   sld.AddState (sld.State_Disabled, cd)
   sld.AddState (sld.State_Pressed, cd)
   sld.AddCatchAllState (cd)
   btn.Background = sld

Any suggestions on how to get it working WITH a bitmap???

 

[yttrium]

Hi,
I'm using the following code but (obviously) this does not work with bitmaps:

   Dim cd As ColorDrawable
   cd.Initialize(Colors.ARGB(127, 255, 128, 128), 5)
   Dim sld As StateListDrawable
   sld.Initialize
   sld.AddState (sld.State_Disabled, cd)
   sld.AddState (sld.State_Pressed, cd)
   sld.AddCatchAllState (cd)
   btn.Background = sld

Any suggestions on how to get it working WITH a bitmap???

You should be sure to also set sld.State_Enabled, the default button value. As for the bitmap, perhaps something using ABExtDrawing would be more akin to your liking:

Dim ed As ABExtDrawing
Dim p As ABPaint
p.SetAlpha(127)
ed.drawBitmap

You should be able to figure out the rest of that, just be sure to use p as the paint for ed.drawBitmap. Basically just draw the bitmap loaded from an image to a new bitmap, and when drawing it use that paint to make it partially transparent. Then set the button to that bitmap.

 

[Informatix]

Hi All,

Is it possible to permanently set the alpha of an item to say 0.5 and then only once the user clicks on it it will become fully opaque?

I am using:

a.InitializeAlpha("a", 0.5, 0.5)
a.Duration = 0 'adjust your blinking speed
a.RepeatCount = 0
a.Start(btn)

i.e. Instead of blinking i want it to stay transparent until clicked on...

As Erel said, you can use my AnimationPlus library to set a transparency level:
a.InitializeAlpha(myButton, 0.5, 0.5)
a.PersistAfter = True
a.Start(myButton)
Then, in the Click event:
a.InitializeAlpha(myButton, 0.5, 1)
a.Start(myButton)

This code allows to do a smooth transition from transparent to opaque. If you don't care of this transition, you can use my Accelerated Surface library. There's a function called AlterColors in the class AS_ImageUtils that allows to modify the transparency (+ hue and saturation) of a bitmap with an optimized algorithm (it can be used in real-time).

 

[francoisg]

Thank you! The hint about using ABExtDrawing worked 100% !!!!