Image Flipping (Mirroring) in ImageView (Android)

Before Flipping

After Flipping

flipped horizontal in mobile

Horizontal Flip

Create new Android Project

Project Name: PlayingwithBitmaps

Build Target: Android 2.3.3   //or greater than that

Application Name: PlayingwithBitmaps

Package Name: com.hamad.playingwithbitmaps

Create Activity: Main

Min SDK: 10 // or greater than that

1. create main layout:

• One image view to display the image.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#000000" >

    <ImageView
        android:id="@+id/imViewAndroid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:src="@drawable/car" />

</RelativeLayout>

 2. code of main activity:

package com.shaikhhamadali.blogspot.playingwithbitmaps;

import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.widget.ImageView;

public class Main extends Activity {
 ImageView imViewAndroid;
 public static final int FLIP_VERTICAL = 1;
 public static final int FLIP_HORIZONTAL = 2;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  imViewAndroid = (ImageView) findViewById(R.id.imViewAndroid);
  imViewAndroid.setImageBitmap(flipImage(BitmapFactory.decodeResource(getResources(), R.drawable.car),2));
 }
 public Bitmap flipImage(Bitmap src, int type) {
  // create new matrix for transformation
  Matrix matrix = new Matrix();
  // if vertical
  if(type == FLIP_VERTICAL) {
   // y = y * -1
   matrix.preScale(1.0f, -1.0f);
  }
  // if horizonal
  else if(type == FLIP_HORIZONTAL) {
   // x = x * -1
   matrix.preScale(-1.0f, 1.0f);
   // unknown type
  } else {
   return null;
  }

  // return transformed image
  return Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
 }
}

3. note that:

• With the help of this,flipImage() method you can flip image on image on click,on action_down,on etc.
• This technique is basically same as rotation, however, it transforms rotation with a reverse direction.
  - For vertical flipping: [ x = x, y = y * -1 ]
  - For horizontal flipping: [ x = x * -1, y = y ]

4. conclusion:

• Some information about Matrix and Image Flipping.
• Know how to flip image bitmap from drawables.

5. About the post:

•  The code seems to explain itself due to comments, and is very easy to understand.
•  Don’t mind to write a comment whatever you like to ask, to know,to suggest or recommend.
•  Hope you enjoy it!

6. Source Code:

        you can download the source code here

Cheers,

Hamad Ali Shaikh