Star Rating in Android

What we will do ?
-> We will create an application with five stars. As we select stars we will get the numbers associated with it.

What we will need ?

LinearLayout and Rating Bar in activity_main.xml

Additions in MainActivity.java

Step 1 : Create a new Application. Go to File->New->Android Application Project.

Step 2 : Give a Name(RatingDemo) and a package name(mia) to your Application. Click Next continuously then click Finish.

Step 3 : Drag RatingBar and Button in activity_main.xml layout.Or else copy the below code in activity_main.xml.

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    <RatingBar
        android:id="@+id/ratingBar1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="50dp"
        android:numStars="5" />
    <Button
        android:id="@+id/button1"
        android:layout_width="174dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="50dp"
        android:text="OK" />
</LinearLayout>

Step 4 : Open MainActivity.java from src->com.mia.ratingdemo. Copy the code below in it.

MainActivity.java

package com.mia.ratingdemo;

import android.os.Bundle;
import android.app.Activity;
import android.view.View;
import android.widget.Button;
import android.widget.RatingBar;
import android.widget.RatingBar.OnRatingBarChangeListener;
import android.widget.Toast;

public class MainActivity extends Activity
{
        RatingBar ratingBar;
        Button btn;
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
   
    ratingBar=(RatingBar)findViewById(R.id.ratingBar1);
    btn=(Button)findViewById(R.id.button1);
    
    ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener() {
        public void onRatingChanged(RatingBar ratingBar, float rating,
        boolean fromUser) {
        Toast.makeText(getApplicationContext(),"Your Selected Ratings  : " + String.valueOf(rating),Toast.LENGTH_LONG).show();
        }
        });


 btn.setOnClickListener(new View.OnClickListener() {         
        public void onClick(View arg0) {
        // TODO Auto-generated method stub
        float rating=ratingBar.getRating();
        Toast.makeText(getApplicationContext(),"Your Selected Ratings  : " + String.valueOf(rating),Toast.LENGTH_LONG).show();
        }
        });
    }

}

Step 5 : Run the Application.

Explanation of the code :

Explanation from activity_main.xml

We just add a RatingBar with a Button in a LinearLayout. numStars:5 is used to limit the rating to 5 .

<RatingBar
        android:id="@+id/ratingBar1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="50dp"
        android:numStars="5" />

Explanation from MainActivity.java

Create a variable of RatingBar as ratingBar and of Button type as btn;

RatingBar ratingBar;
Button btn;

We relate the rating bar and the button from the layout to the variables respectively using findViewById().

ratingBar=(RatingBar)findViewById(R.id.ratingBar1);
btn=(Button)findViewById(R.id.button1);

the onRatingBarChangeListener() method is used to perform action on clicking the RatingBar. Here we will display a Toast with the number of starts given by the user, when the action is performed.The float rating variable stores the rating value in float number.

ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener() {
        public void onRatingChanged(RatingBar ratingBar, float rating,
        boolean fromUser) {
        Toast.makeText(getApplicationContext(),"Your Selected Ratings  : " + String.valueOf(rating),Toast.LENGTH_LONG).show();