How to rotate shape on canvas to any specified degrees angle on android activity on button click.

In this tutorial we are using canvas.rotate() method to rotate the rectangle shape above canvas. So here is the complete step by step tutorial for Rotate Rectangle shape on Canvas in android programmatically.

How to Rotate Rectangle shape on Canvas in android programmatically.

Code for MainActivity.java file.

 package com.rotaterectangleshapeoncanvas_android_examples.com;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;


public class MainActivity extends Activity {

 ImageView imageview;
 Button button;
 Bitmap bitmap;
 Canvas canvas;
 Paint paint;
 int ShapePadding = 80;
 Rect rectangleShape;
 int degreesAngle = 35 ;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 
 imageview = (ImageView)findViewById(R.id.imageView1);
 button = (Button)findViewById(R.id.button1);
 
 button.setOnClickListener(new View.OnClickListener() {
 
 @Override
 public void onClick(View v) {
 // TODO Auto-generated method stub
 
 CreateBitmap();

 CreateCanvas();
 
 CreatePaint();
 
 canvas.save(Canvas.MATRIX_SAVE_FLAG);
 
 canvas.rotate(
 degreesAngle,
 canvas.getWidth() / 2,
 canvas.getHeight() / 2
 );
 
 CreateRectangleShape(); 
 
 imageview.setImageBitmap(bitmap);
 
 }
 });
 }
 
 public void CreateBitmap(){
 
 bitmap = Bitmap.createBitmap(
 400,
 300,
 Bitmap.Config.RGB_565
 );
 
 }
 
 public void CreateCanvas(){
 
 canvas = new Canvas(bitmap);

 canvas.drawColor(Color.CYAN);
 
 }
 
 public void CreatePaint(){
 
 paint = new Paint();
 
 paint.setStyle(Paint.Style.FILL);
 
 paint.setColor(Color.BLUE);
 
 paint.setAntiAlias(true);
 
 }
 
 public void CreateRectangleShape()
 {
 canvas.drawRect(
 ShapePadding,
 ShapePadding,
 canvas.getWidth() - ShapePadding,
 canvas.getHeight() - ShapePadding,
 paint
 );

 canvas.restore();
 
 } 
 
}

Code for activity_main.xml layout file.

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:paddingBottom="@dimen/activity_vertical_margin"
 android:paddingLeft="@dimen/activity_horizontal_margin"
 android:paddingRight="@dimen/activity_horizontal_margin"
 android:paddingTop="@dimen/activity_vertical_margin"
 tools:context="com.rotaterectangleshapeoncanvas_android_examples.com.MainActivity" >

 <ImageView
 android:id="@+id/imageView1"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_alignParentTop="true"
 android:layout_centerHorizontal="true"
 />

 <Button
 android:id="@+id/button1"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_centerHorizontal="true"
 android:layout_centerVertical="true"
 android:text="How to Rotate Rectangle shape on Canvas in android programmatically" />

</RelativeLayout>

Screenshot: