Android implements an example of drawing operations in View via onDraw
- 2020-05-17 06:28:03
- OfStack
The Android drawing operation, which is implemented by inheriting View, is implemented in the onDraw function.
Here's a simple example:
Here's a simple example:
public class AndroidTest extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyView mv = new MyView(this);
setContentView(mv);
}
public class MyView extends View {
MyView(Context context) {
super(context);
}
@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
// First of all define 1 a paint
Paint paint = new Paint();
// Draw a rectangular area - Solid rectangular
// Set the color
paint.setColor(Color.BLUE);
// Set the style - fill
paint.setStyle(Style.FILL);
// draw 1 A rectangular
canvas.drawRect(new Rect(0, 0, getWidth(), getHeight()), paint);
// Draw hollow rectangle
// Set the color
paint.setColor(Color.RED);
// Set the style - A hollow rectangular
paint.setStyle(Style.STROKE);
// draw 1 A rectangular
canvas.drawRect(new Rect(10, 10, 100, 30), paint);
// Paint with words
// Set the color
paint.setColor(Color.GREEN);
// Paint with words
canvas.drawText("Hello", 10, 50, paint);
// drawing
// Generate bitmaps from resource files
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
// drawing
canvas.drawBitmap(bitmap, 10, 60, paint);
}
}
}