I'm taking screenshots in Android Jelly Bean (using Galaxy Nexus)
using DDMS I can take screenshot. Like this.
In Home Screen
But here's the problem.
When I opened the camera app and take a screenshot from DDMS.
Result is... A Black Image...
Even in device It can't take also screenshot.
Why is this happening??
Any help will be appreciated..
Try going to the Android Virtual Device Manager, edit the affected device, and uncheck "Use Host GPU" under Emulation Options near the bottom of the window.
It's probably that the camera image is being fed directly to the framebuffer using a video overlay on this device, rather than going through the usual rendering path. Thus the 'main' framebuffer is empty.
This is the same sort of problem you often see on PC if you try to take a screenshot of a video player or some other software that uses an overlay: you get a grey or blue box on the screen where the overlaid content ought to be. The mechanism is a little different, because Android's composition framework does a lot more of this behind the scenes, but the root is the same.
Since this is to do with how camera images are composited on this device, you could avoid the problem by using a device with a different chipset. For example, Samsung's i9300 can take screenshots of the camera app.
