How to resize Image in Android App?

This example demonstrate about How to resize Image in Android App.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<? xml version= "1.0" encoding= "utf-8" ?>
<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 :gravity= "center"
   tools :context= ".MainActivity" >
   <ImageView
      android :id= "@+id/ivImage"
      android :layout_width= "wrap_content"
      android :layout_height= "wrap_content"
      android :layout_centerHorizontal= "true"
      android :contentDescription= "@string/app_name"
      android :src= "@drawable/ic_launcher_foreground" />
   <LinearLayout
      android :layout_width= "match_parent"
      android :layout_height= "wrap_content"
      android :layout_below= "@+id/ivImage"
      android :layout_centerHorizontal= "true" >
      <Button
         android :layout_width= "0dp"
         android :layout_height= "wrap_content"
         android :layout_marginTop= "8dp"
         android :layout_weight= "1"
         android :onClick= "uploadImage"
         android :text= "Upload Image" />
      <Button
         android :layout_width= "0dp"
         android :layout_height= "wrap_content"
         android :layout_marginTop= "8dp"
         android :layout_weight= "1"
         android :onClick= "resizeImage"
         android :text= "Resize Image" />
   </LinearLayout>
</RelativeLayout>

Step 3 − Add the following code to src/MainActivity.java

package app.tutorialspoint.com.sample ;
import android.app.Activity ;
import android.content.Intent ;
import android.graphics.Bitmap ;
import android.net.Uri ;
import android.provider.MediaStore ;
import android.support.v7.app.AppCompatActivity ;
import android.os.Bundle ;
import android.view.View ;
import android.widget.ImageView ;
import java.io.IOException ;
public class MainActivity extends AppCompatActivity {
   ImageView ivImage ;
   public static final int PICK_IMAGE = 1 ;
   Bitmap yourBitmap ;
   @Override
   protected void onCreate (Bundle savedInstanceState) {
      super .onCreate(savedInstanceState) ;
      setContentView(R.layout. activity_main ) ;
      ivImage = findViewById(R.id. ivImage ) ;
   }
   public void uploadImage (View view) {
      Intent intent = new Intent(Intent. ACTION_GET_CONTENT ) ;
      intent.setType( "image/*" ) ;
      startActivityForResult(intent , PICK_IMAGE ) ;
   }
   public void resizeImage (View view) {
      Bitmap resized = Bitmap. createScaledBitmap ( yourBitmap , 400 , 400 , true ) ;
      ivImage .setImageBitmap(resized) ;
   }
   @Override
   public void onActivityResult ( int requestCode , int resultCode , Intent data) {
      super .onActivityResult(requestCode , resultCode , data) ;
      if (requestCode == PICK_IMAGE && resultCode == Activity. RESULT_OK ) {
         if (data == null ) {
            //Display an error
            return;
         }
         try {
            Uri imageUri = data.getData() ;
            yourBitmap =
            MediaStore.Images.Media. getBitmap ( this .getContentResolver() , imageUri) ;
            ivImage .setImageBitmap( yourBitmap ) ;
         } catch (IOException e) {
            e.printStackTrace() ;
         }
      }
   }
}

Step 4 − Add the following code to androidManifest.xml

<? xml version= "1.0" encoding= "utf-8" ?>
<manifest xmlns: android = "http://schemas.android.com/apk/res/android"
   package= "app.tutorialspoint.com.sample" >
   <application
      android :allowBackup= "true"
      android :icon= "@mipmap/ic_launcher"
      android :label= "@string/app_name"
      android :roundIcon= "@mipmap/ic_launcher_round"
      android :supportsRtl= "true"
      android :theme= "@style/AppTheme" >
      <activity android :name= ".MainActivity" >
         <intent-filter>
            <action android :name= "android.intent.action.MAIN" />
            <category android :name= "android.intent.category.LAUNCHER" />
         </intent-filter>
      </activity>
   </application>
</manifest>