Play Sound Android Example

Warning in AndroidManifest.xml:
tag should specify a target API level (the highest verified version; when running on
later versions, compatibility behaviors may be enabled) with android:targetSdkVersion="?"

Solution:

    <uses-sdk android:minSdkVersion="4"
         android:targetSdkVersion="16" />

If you create a button or view programmatically with OnClickListener you can set a tag key before button in parent layout is added.
And get correct button by this tag getTag() instead getId() in OnClickListener etc.

Button button = new Button(getApplicationContext());
int idOfButton = button.getId(); // return -1

button.setTag("my_button");
String sTag = (String) button.getTag(); // return "my_button"

drawArc(), Canvas, Paint, setStyle()

public class MainActivity extends Activity {
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {

		// CONSTRUCTOR
		public SampleView(Context context) {
			super(context);
			setFocusable(true);

		}

		@Override
		protected void onDraw(Canvas canvas) {

			canvas.drawColor(Color.CYAN);
			Paint p = new Paint();
			// smooths
			p.setAntiAlias(true);
			p.setColor(Color.RED);
			p.setStyle(Paint.Style.STROKE); 
			p.setStrokeWidth(5);
			// opacity
			//p.setAlpha(0x80); //
 
			RectF rectF = new RectF(50, 20, 100, 80);
			canvas.drawOval(rectF, p);
			p.setColor(Color.BLACK);
			canvas.drawArc (rectF, 90, 45, true, p);
		}

	}
}

Cut, shear, clip, snip, crop a bitmap, picture, image Android example

public class ApokusActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {

		// CONSTRUCTOR
		public SampleView(Context context) {
			super(context);
			setFocusable(true);

		}

		@Override
		protected void onDraw(Canvas canvas) {
			Paint paint = new Paint();

			canvas.drawColor(Color.YELLOW);


			// you need to insert a image flower_blue into res/drawable folder
			paint.setFilterBitmap(true);
			Bitmap bitmapOrg = BitmapFactory.decodeResource(getResources(),
					R.drawable.flower_blue);

			Bitmap croppedBmp = Bitmap.createBitmap(bitmapOrg, 0, 0,
					bitmapOrg.getWidth() / 2, bitmapOrg.getHeight());
			int h = bitmapOrg.getHeight();
			canvas.drawBitmap(bitmapOrg, 10, 10, paint);
			canvas.drawBitmap(croppedBmp, 10, 10 + h + 10, paint);

		}

	}
}

Select file in project explorer
Menu:
File - Make File Read-only - to lock
File - Make File Writable - to unlock