How to work with Picasso in Android

This example demonstrates how to work with Picasso

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:id="@+id/activity_main"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="16dp"
   tools:context=".MainActivity">
<Button
   android:id="@+id/btnDrawable"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignParentStart="true"
   android:layout_centerVertical="true"
   android:text="Drawable" />
<ImageView
   android:id="@+id/imageView"
   android:layout_width="200dp"
   android:layout_height="200dp"
   android:layout_centerHorizontal="true"
   android:src="@mipmap/ic_launcher" />
<Button
   android:id="@+id/btnPlaceholder"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignBaseline="@+id/btnUrl"
   android:layout_alignBottom="@+id/btnUrl"
   android:layout_centerHorizontal="true"
   android:text="Placeholder" />
<Button
   android:id="@+id/btnUrl"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignBaseline="@+id/btnDrawable"
   android:layout_alignBottom="@+id/btnDrawable"
   android:layout_alignParentEnd="true"
   android:text="URL" />
<Button
   android:id="@+id/btnError"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_below="@+id/btnDrawable"
   android:layout_alignParentStart="true"
   android:layout_marginTop="12dp"
   android:text="Error" />
<Button
   android:id="@+id/btnCallBack"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignBaseline="@+id/btnError"
   android:layout_alignStart="@+id/btnPlaceholder"
   android:layout_alignBottom="@+id/btnError"
   android:text="Callback" />
<Button
   android:id="@+id/btnResize"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignBaseline="@+id/btnCallBack"
   android:layout_alignBottom="@+id/btnCallBack"
   android:layout_alignParentEnd="true"
   android:text="Resize" />
<Button
   android:id="@+id/btnRotate"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_below="@+id/btnError"
   android:layout_alignParentStart="true"
   android:layout_marginTop="12dp"
   android:text="Rotate" />
<Button
   android:id="@+id/btnScale"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignStart="@+id/btnCallBack"
   android:layout_alignBottom="@+id/btnTarget"
   android:text="Scale" />
<Button
   android:id="@+id/btnTarget"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_alignBaseline="@+id/btnRotate"
   android:layout_alignBottom="@+id/btnRotate"
   android:layout_alignParentEnd="true"
   android:text="Targets" />
</RelativeLayout>

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

package app.com.sample;
import androidx.appcompat.app.AppCompatActivity;
import android.graphics.Bitmap;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import com.squareup.picasso.Callback;
import com.squareup.picasso.Picasso;
import com.squareup.picasso.Target;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
   ImageView imageView;
   int i = 0;
   Button btnDrawableImage, btnUrlImage, btnErrorImage, btnPlaceholderImage, btnCallback, btnResizeImage,
   btnRotateImage, btnScaleImage, btnTarget;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      initView();
   }
   private void initView() {
      imageView = findViewById(R.id.imageView);
      btnDrawableImage = findViewById(R.id.btnDrawable);
      btnUrlImage = findViewById(R.id.btnUrl);
      btnPlaceholderImage = findViewById(R.id.btnPlaceholder);
      btnErrorImage = findViewById(R.id.btnError);
      btnCallback = findViewById(R.id.btnCallBack);
      btnResizeImage = findViewById(R.id.btnResize);
      btnRotateImage = findViewById(R.id.btnRotate);
      btnScaleImage = findViewById(R.id.btnScale);
      btnTarget = findViewById(R.id.btnTarget);
      btnDrawableImage.setOnClickListener(this);
      btnPlaceholderImage.setOnClickListener(this);
      btnUrlImage.setOnClickListener(this);
      btnCallback.setOnClickListener(this);
      btnResizeImage.setOnClickListener(this);
      btnErrorImage.setOnClickListener(this);
      btnRotateImage.setOnClickListener(this);
      btnScaleImage.setOnClickListener(this);
      btnTarget.setOnClickListener(this);
   }
   @Override
   public void onClick(View view) {
      switch (view.getId()) {
         case R.id.btnDrawable:
         Picasso.with(this).load(R.drawable.image).into(imageView);
         break;
         case R.id.btnPlaceholder:
         Picasso.with(this).load("www.journaldev.com").placeholder(R.drawable.placeholder).into(imageView);
      break;
      case R.id.btnUrl:
      Picasso.with(this).load("http://cdn.journaldev.com/wp-content/uploads/2017/01/android-         constraintlayout-sdk-tool-install.png").placeholder(R.drawable.placeholder).into(imageView);
      break;
      case R.id.btnError:
   Picasso.with(this).load("www.journaldev.com").placeholder(R.drawable.placeholder).error(R.drawable.
error).into(imageView);
      break;
      case R.id.btnCallBack:
      Picasso.with(this).load("www.journaldev.com").error(R.mipmap.ic_launcher).into(imageView, new Callb ack() {
      @Override
      public void onSuccess() {
         Log.d("TAG", "onSuccess");
      }
      @Override
      public void onError() {
         Toast.makeText(getApplicationContext(), "An error occurred", Toast.LENGTH_SHORT).show();
      }
   });
   break;
   case R.id.btnResize:
   Picasso.with(this).load(R.drawable.image).resize(200, 200).into(imageView);
   break;
   case R.id.btnRotate:
   Picasso.with(this).load(R.drawable.image).rotate(90f).into(imageView);
   break;
   case R.id.btnScale:
   if (i == 3)
   i = 0;
   else {
      if (i == 0) {
      Picasso.with(this).load(R.drawable.image).fit().into(imageView);
      Toast.makeText(getApplicationContext(), "Fit", Toast.LENGTH_SHORT).show();
   }
    else if (i == 1) {
      Picasso.with(this).load(R.drawable.image).resize(200, 200).centerCrop().into(imageView);
      Toast.makeText(getApplicationContext(), "Center Crop", Toast.LENGTH_SHORT).show();
   }
   else if (i == 2) {
      Picasso.with(this).load(R.drawable.image).resize(200, 200).centerInside().into(imageView);
      Toast.makeText(getApplicationContext(), "Center Inside", Toast.LENGTH_SHORT).show();
   }
   i++;
}
break;
   case R.id.btnTarget:
   Picasso.with(this).load("http://cdn.journaldev.com/wp-content/uploads/2017/01/android-      constraintlayout-sdk-tool-      install.png").placeholder(R.drawable.placeholder).error(R.drawable.error).into(target);
   break;
   }
}
private Target target = new Target() {
   @Override
   public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
      imageView.setImageBitmap(bitmap);
   }
   @Override
   public void onBitmapFailed(Drawable errorDrawable) {
      imageView.setImageDrawable(errorDrawable);
   }
   @Override
   public void onPrepareLoad(Drawable placeHolderDrawable) {
      imageView.setImageDrawable(placeHolderDrawable);
      }
   };
}

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.com.sample">
   <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
   <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>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from the android studio, open one of your project's activity files and click the Run icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −