How to save draw paint with custom view android?

android, bitmap, drawing, paint, save

Solution

I made a few changes to your code and it works. I also added a save option.

public class FingerPaintActivity extends GraphicsActivity implements ColorPickerDialog.OnColorChangedListener {    

MyView mv;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   mv= new MyView(this);
   mv.setDrawingCacheEnabled(true);
   setContentView(mv);
   mPaint = new Paint();
   mPaint.setAntiAlias(true);
   mPaint.setDither(true);
   mPaint.setColor(0xFFFF0000); 
   mPaint.setStyle(Paint.Style.STROKE);
   mPaint.setStrokeJoin(Paint.Join.ROUND);
   mPaint.setStrokeCap(Paint.Cap.ROUND);
   mPaint.setStrokeWidth(12);

   mEmboss = new EmbossMaskFilter(new float[] { 1, 1, 1 },
                           0.4f, 6, 3.5f);

   mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL);
   }

   private Paint       mPaint;
   private MaskFilter  mEmboss;
   private MaskFilter  mBlur;

   public void colorChanged(int color) {
   mPaint.setColor(color);
   }

   public class MyView extends View {

   private static final float MINP = 0.25f;
   private static final float MAXP = 0.75f;

   private Bitmap  mBitmap;
   private Canvas  mCanvas;
   private Path    mPath;
   private Paint   mBitmapPaint;
   Context context;

   public MyView(Context c) {
    super(c);
    context=c;

  //mBitmap = Bitmap.createBitmap(320, 480, Bitmap.Config.ARGB_8888);


   mPath = new Path();
   mBitmapPaint = new Paint(Paint.DITHER_FLAG);
  }

  @Override
  protected void onSizeChanged(int w, int h, int oldw, int oldh) {
  super.onSizeChanged(w, h, oldw, oldh);
  mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
  mCanvas = new Canvas(mBitmap);
  }

 @Override
 protected void onDraw(Canvas canvas) {
 canvas.drawColor(0xFFAAAAAA);

 canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);

 canvas.drawPath(mPath, mPaint);
 }

private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;

private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
} 
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
    mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
    mX = x;
    mY = y;
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
// commit the path to our offscreen
mCanvas.drawPath(mPath, mPaint);
// kill this so we don't double draw
mPath.reset();
mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SCREEN));
mPaint.setMaskFilter(null);
}

@Override
public boolean onTouchEvent(MotionEvent event) {
float x = event.getX();
float y = event.getY();

switch (event.getAction()) {
    case MotionEvent.ACTION_DOWN:
        touch_start(x, y);
        invalidate();
        break;
    case MotionEvent.ACTION_MOVE:
        touch_move(x, y);
        invalidate();
        break;
    case MotionEvent.ACTION_UP:
        touch_up();
        invalidate();
        break;
}
return true;
}
}

 private static final int COLOR_MENU_ID = Menu.FIRST;
 private static final int EMBOSS_MENU_ID = Menu.FIRST + 1; 
 private static final int BLUR_MENU_ID = Menu.FIRST + 2;
 private static final int ERASE_MENU_ID = Menu.FIRST + 3;
 private static final int SRCATOP_MENU_ID = Menu.FIRST + 4;
 private static final int Save = Menu.FIRST + 5;

 @Override 
  public boolean onCreateOptionsMenu(Menu menu) {
  super.onCreateOptionsMenu(menu);

    menu.add(0, COLOR_MENU_ID, 0, "Color").setShortcut('3', 'c');
    menu.add(0, EMBOSS_MENU_ID, 0, "Emboss").setShortcut('4', 's');
    menu.add(0, BLUR_MENU_ID, 0, "Blur").setShortcut('5', 'z');
    menu.add(0, ERASE_MENU_ID, 0, "Erase").setShortcut('5', 'z');
    menu.add(0, SRCATOP_MENU_ID, 0, "SrcATop").setShortcut('5', 'z');
    menu.add(0, Save, 0, "Save").setShortcut('5', 'z');

     /****   Is this the mechanism to extend with filter effects?
     Intent intent = new Intent(null, getIntent().getData());
     intent.addCategory(Intent.CATEGORY_ALTERNATIVE);
     menu.addIntentOptions(
                  Menu.ALTERNATIVE, 0,
                  new ComponentName(this, NotesList.class),
                  null, intent, 0, null);
      *****/
      return true;
      }

      @Override
       public boolean onPrepareOptionsMenu(Menu menu) {
       super.onPrepareOptionsMenu(menu);
        return true;
        }

@Override
public boolean onOptionsItemSelected(MenuItem item) {
mPaint.setXfermode(null);
mPaint.setAlpha(0xFF);

switch (item.getItemId()) {
case COLOR_MENU_ID:
    new ColorPickerDialog(this, this, mPaint.getColor()).show();
    return true;
case EMBOSS_MENU_ID:
    if (mPaint.getMaskFilter() != mEmboss) {
        mPaint.setMaskFilter(mEmboss);
    } else {
        mPaint.setMaskFilter(null);
    }
    return true;
case BLUR_MENU_ID:
    if (mPaint.getMaskFilter() != mBlur) {
        mPaint.setMaskFilter(mBlur);
    } else {
        mPaint.setMaskFilter(null);
    }
    return true;
case ERASE_MENU_ID:
    mPaint.setXfermode(new PorterDuffXfermode(
                                            PorterDuff.Mode.CLEAR));
    return true;
case SRCATOP_MENU_ID:

    mPaint.setXfermode(new PorterDuffXfermode(
                                        PorterDuff.Mode.SRC_ATOP));
    mPaint.setAlpha(0x80);
    return true;
case Save:
    AlertDialog.Builder editalert = new AlertDialog.Builder(FingerPaintActivity.this);
        editalert.setTitle("Please Enter the name with which you want to Save");
        final EditText input = new EditText(FingerPaintActivity.this);
        LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                LinearLayout.LayoutParams.FILL_PARENT,
                LinearLayout.LayoutParams.FILL_PARENT);
        input.setLayoutParams(lp);
        editalert.setView(input);
        editalert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {

            String name= input.getText().toString();
            Bitmap bitmap = mv.getDrawingCache();

         String path = Environment.getExternalStorageDirectory().getAbsolutePath(); 
            File file = new File("/sdcard/"+name+".png");           
            try 
            {
                if(!file.exists())
            {
                file.createNewFile();
            }
                FileOutputStream ostream = new FileOutputStream(file);
                bitmap.compress(CompressFormat.PNG, 10, ostream);
                    System.out.println("saving......................................................"+path);
                ostream.close();
                mv.invalidate();                            
            } 
            catch (Exception e) 
            {
                e.printStackTrace();
            }finally
            {

                mv.setDrawingCacheEnabled(false);                           
            }
            }
        });

        editalert.show();       
    return true;    
}
 return super.onOptionsItemSelected(item);
}
}

Edit :

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap);
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.afor);
mCanvas.drawBitmap(bmp, 0, 0, mPaint);
}

Problem

Original source