Android: How to Capture Screen in Gingerbread (screenshot in 2.3)

 

The sample code is as follows:

Frameworks \ base \ services \ surfaceflinger \ tests \ screencap. cpp

 

/*

* Copyright (C) 2010 The Android Open Source Project

*

* Licensed under the Apache License, Version 2.0 (the "License ");

* You may not use this file before t in compliance with the License.

* You may obtain a copy of the License

*

* Http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* Distributed under the License is distributed on an "as is" BASIS,

* Without warranties or conditions of any kind, either express or implied.

* See the License for the specific language governing permissions and

* Limitations under the License.

*/

 

# Include <utils/Log. h>

 

# Include <binder/IPCThreadState. h>

# Include <binder/ProcessState. h>

# Include <binder/IServiceManager. h>

 

# Include <binder/IMemory. h>

# Include <surfaceflinger/ISurfaceComposer. h>

 

# Include <SkImageEncoder. h>

# Include <SkBitmap. h>

 

Using namespace android;

 

Int main (int argc, char ** argv)

{

If (argc! = 2 ){

Printf ("usage: % s path \ n", argv [0]);

Exit (0 );

}

 

Const String16 name ("SurfaceFlinger ");

Sp <ISurfaceComposer> composer;

GetService (name, & composer );

 

Sp <IMemoryHeap> heap;

Uint32_t w, h;

PixelFormat f;

Status_t err = composer-> captureScreen (0, & heap, & w, & h, & f, 0, 0 );

If (err! = NO_ERROR ){

Fprintf (stderr, "screen capture failed: % s \ n", strerror (-err ));

Exit (0 );

}

 

Printf ("screen capture success: w = % u, h = % u, pixels = % p \ n ",

W, h, heap-> getBase ());

 

Printf ("saving file as PNG in % s... \ n", argv [1]);

 

SkBitmap B;

B. setConfig (SkBitmap: kARGB_8888_Config, w, h );

B. setPixels (heap-> getBase ());

SkImageEncoder: EncodeFile (argv [1], B,

SkImageEncoder: kPNG_Type, SkImageEncoder: kDefaultQuality );

 

Return 0;

}

Compile and generate/system/bin/test-screencap

Enter test-screencap/mnt/sdcard/scapxx.png

You can see scapxx.png. The default size is the screen resolution.

 

If you want to write this function to your own application

Write a JNI file. Refer to the code above, but remember the permission statement.

 

<Span style = "font-size: 24px;"> <uses-permission android: name = "android. permission. READ_FRAME_BUFFER"/> </span>

 

Of course, it is best to implement it at the system level and respond to a combination of keys for screenshots, such as Android4.0.

 

Author zmyde2010