Fading images i live wallpaper


Licensed User
Longtime User
I started writing a live wall paper using Erels tutorial live wallpaper image.
I select different fotos I have on my device and with the timer show them every 10 seconds.
It all works fine, but now I want to make a fade in and out on every change of the foto, can't find to work it out.
Is there someone who can help me.

Bye, Pal57


Licensed User
Longtime User
I've moved your thread to the questions forum.

You will need to manually draw the fading effect. You should use the timer and draw a semi transparent layer above the image.

Hello Erel, I am struggling with the same problem at the moment. If we try to draw fading images in the live wallpaper context, then we would have to draw it on the engine.canvas and it does not seem to support an alpha parameter out of the box. So I searched for other objects and libraries I could work with. Accelerated surface seems to work only with imageviews, so nothing I can use in a LWP. Animation and Animation Plus do not seem to work either. RSImageprocessing has a lot of powerful features but none to change the alpha value from what I could see..... It can tell you if a bitmap has alpha and it can invert an image and even extract alpha but not change alpha.....

I can imagine that it would work if one takes a bitmap, parses the channels (including alpha channel that should be 100% if the image was opaque) and then rebuilds the rgb channels with alpha channel set to 50% or so.....

I am quite new as you may already have discovered, and am not sure if I will get this to work. Seems quite a challenge for a newbie...
So my question: Is there a library that already can set an alpha on a bitmap and which is fast enough for realtime rendering?
I have read some entries and posts here asking for methods to fade in / out images. This is exactly what I am also trying to do but it seems as if nobody found a solution so far in the live wallpaper context....

I know you are busy and I don't expect to work out the solution, but if you could tell me an out of the box lib, then it would help me a lot. If not, then I will have to figure out a way myself. IN this case maybe you can tell me the right approach (without working it out in detail).

Many thanks in advance.
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