I have a code in which,I am placing an Image on the canvas and tries to draw on it with Fingerpaint. But while I am using the Eraser to erase the last drawn lines or something with Fingerpaint, It is erasing the background image also...I am copying the code below.If you have any solution,please let me know.
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
String pathName = Environment.getExternalStorageDirectory().toString()+"/test.jpg";
Bitmap image = LoadBMPsdcard(pathName);
// 开发者_如何转开发Bitmap image = BitmapFactory.decodeResource(getResources(),R.drawable.hp).copy(Bitmap.Config.ARGB_8888, true);
mBitmap = Bitmap.createScaledBitmap(image, sketchBoard.getWidth(), sketchBoard.getHeight(), true);
//mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap);
}
private Bitmap LoadBMPsdcard(String path)
{
//creates a 'File' object, to check if the image exists (Thanks to Jbeerdev for the tip)
File imageFile = new File(path);
//if the file exists
if(imageFile.exists())
{
//load the bitmap from the given path
return BitmapFactory.decodeFile(path).copy(Bitmap.Config.ARGB_8888, true);
}
else
{
//return the standard 'Image not found' bitmap placed on the res folder
return BitmapFactory.decodeResource(getResources(), R.drawable.imagenotfound).copy(Bitmap.Config.ARGB_8888, true);
}
}
@Override
protected void onDraw(Canvas canvas) {
try{
canvas.drawColor(0x000FFF);
//canvas.drawBitmap(mBitmap, srcRect, dstRect,mBitmapPaint);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mPath, mPaint);
}catch(Exception e){
e.printStackTrace();
}
}
And the menu part that includes the eraser option is....
public boolean onOptionsItemSelected(MenuItem item) {
mPaint.setXfermode(null);
mPaint.setAlpha(0xFF);
switch (item.getItemId()) {
case R.id.newf:
sketchBoard.removeAllViews();
view.invalidate();
view= new MyView(this);
setContentView(view);
return true;
case R.id.red:
// mPaint.reset();
mPaint.setColor(0xFF3300);
mPaint.setAntiAlias(true);
//view.invalidate();
return true;
case R.id.white:
// mPaint.reset();
mPaint.setColor(0xFFFFFF);
mPaint.setAntiAlias(true);
// view.invalidate();
return true;
case R.id.blue:
//mPaint.reset();
mPaint.setColor(0x0033FF);
// view.invalidate();
return true;
case R.id.save:
cReatePNG();
return true;
case R.id.eraser:
mPaint.setXfermode(new PorterDuffXfermode(
PorterDuff.Mode.CLEAR));
return true;
case R.id.reset:
sketchBoard.removeAllViews();
view.invalidate();
view= new MyView(this);
setContentView(view);
return true;
case R.id.exit:
finish();
}
return super.onOptionsItemSelected(item);
}
Thanks in Advance
Arun
if you are just trying to clear the path that you have drawn then just call
mPath.reset();
invalidate();
setbackground to your draw view and
at canvas.drawColor(0x000FFF);
replace with canvas.drawColor(0x00000000);
Try placing the picture on a different layout. I am working on a similar project and I ran into the same issue. I used the following view:
<FrameLayout
android:layout_width="fill_parent"
android:id="@+id/get_user_fingerpaint"
android:layout_height="fill_parent">
<ImageView
android:id="@+id/main_image"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</FrameLayout>
Then in my application I placed the background image on the ImageView and I write on the FrameLayout. This way you never alter your original image.
Hope it helps.
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