Screenshot in android

Question

Below is the code that I use to take a screenshot using GLSurfaceView. But I do not know why the onDraw () method in the GLSurfaceView.Renderer class is not called.

Please, if someone can look at the code below and indicate what I'm doing wrong.

public class MainActivity extends Activity {

    private GLSurfaceView mGLView;
    int x,y,w,h;
    Display disp;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        // ToDo add your GUI initialization code here

        setContentView(R.layout.main);
        x=0;
        y=0;

        disp = getWindowManager().getDefaultDisplay();

        w = disp.getWidth();
        h = disp.getHeight();

       mGLView = new ClearGLSurfaceView(this);


    }

    class ClearGLSurfaceView extends GLSurfaceView {
    public ClearGLSurfaceView(Context context) {
        super(context);
        setDebugFlags(DEBUG_CHECK_GL_ERROR | DEBUG_LOG_GL_CALLS);
        mRenderer = new ClearRenderer();
        setRenderer(mRenderer);
    }

        ClearRenderer mRenderer;
}


    class ClearRenderer implements GLSurfaceView.Renderer {

    public void onSurfaceCreated(GL10 gl, EGLConfig config) {
        // Do nothing special.
    }

    public void onSurfaceChanged(GL10 gl, int w, int h) {
        //gl.glViewport(0, 0, w, h);
    }

    public void onDrawFrame(GL10 gl) {
        //gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
        int b[]=new int[w*(y+h)];

         int bt[]=new int[w*h];

         IntBuffer ib=IntBuffer.wrap(b);

         ib.position(0);

         gl.glReadPixels(x, 0, w, y+h, GL10.GL_RGBA, GL10.GL_UNSIGNED_BYTE, ib);



         for(int i=0, k=0; i<h; i++, k++)

         {//remember, that OpenGL bitmap is incompatible with Android bitmap

          //and so, some correction need.

              for(int j=0; j<w; j++)

              {

                   int pix=b[i*w+j];

                   int pb=(pix>>16)&0xff;

                   int pr=(pix<<16)&0x00ff0000;

                   int pix1=(pix&0xff00ff00) | pr | pb;

                   bt[(h-k-1)*w+j]=pix1;

              }

         }




         Bitmap bmp = Bitmap.createBitmap(bt, w, h,Bitmap.Config.ARGB_8888);

         try

                {
                        File f = new File("/sdcard/testpicture.png");
                        f.createNewFile();
                        FileOutputStream fos=new FileOutputStream(f);

                        bmp.compress(CompressFormat.PNG, 100, fos);

                        try

                        {

                                fos.flush();

                        }

                        catch (IOException e)

                        {

                                // TODO Auto-generated catch block

                                e.printStackTrace();

                        }

                        try

                        {

                                fos.close();

                        }

                        catch (IOException e)

                        {

                                // TODO Auto-generated catch block

                                e.printStackTrace();

                        }



                }

                catch (FileNotFoundException e)

                {

                        // TODO Auto-generated catch block

                        e.printStackTrace();

                }
                catch(IOException e)
                {
                    e.printStackTrace();
                }

    }
}

}

Please help me. I just started learning to work on Android.

Answer 1

Although you create a surface view, you do not set it as the current content

setContentView(mGLView);

In addition, you create a screenshot of each frame, which is very inefficient and probably not what you need.