Draw something on a Canvas

Simple draw something (drawRect) on a Canvas over a bitmap on a View.



Modify from the previous article "Draw a bitmap on View". In order to draw something, a object of Paint class have to been create, and set some parameter; such as color, style, Strok.

Modify the code:

package com.exercise.AndroidPaint;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Bundle;
import android.view.View;

public class AndroidPaint extends Activity {
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      //setContentView(R.layout.main);
      setContentView(new myView(this));
  }

  private class myView extends View{

public myView(Context context) {
 super(context);
 // TODO Auto-generated constructor stub
}

@Override
protected void onDraw(Canvas canvas) {
 // TODO Auto-generated method stub
 Bitmap myBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.googlelogo320x480);
          canvas.drawBitmap(myBitmap, 0, 0, null);
        
          Paint myPaint = new Paint();
          myPaint.setColor(Color.GREEN);
          myPaint.setStyle(Paint.Style.STROKE);
          myPaint.setStrokeWidth(3);
          canvas.drawRect(10, 10, 100, 100, myPaint);
}
  }
}

Download the files.

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Next: Custom View with User Interaction