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

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>