Android button Example With Listerner | Android Example | Button

Android button Example

Android Button speaks to a push-catch. The android.widget.Button is subclass of TextView class and CompoundButton is the subclass of Button class.

There are distinctive kinds of catches in android, for example, RadioButton, ToggleButton, CompoundButton and so on.

Android button Example With Listerner

Here, we will make two textfields and one catch for whole of two numbers. In the event that client clicks catch, aggregate of two information esteems is shown on the Toast.

We can perform activity on catch utilizing distinctive sorts, for example, calling audience on catch or including onClick property of catch in action's xml record.

button.setOnClickListener(new View.OnClickListener() {  

            @Override  

            public void onClick(View view) {  

               //code  

            }  

});  

<Button  

        android:onClick="methodName"  

/>

Drag The component of write the code for  UI in activity_main.xml

Above all else, drag 2 textfields from the Text Fields palette and one catch from the Form Widgets palette as appeared in the accompanying figure.

File :- activity_main.xml

<?xml version="1.0" encoding="utf-8"?>  

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  

    xmlns:app="http://schemas.android.com/apk/res-auto"  

    xmlns:tools="http://schemas.android.com/tools"  

    android:layout_width="match_parent"  

    android:layout_height="match_parent"  

    tools:context="example.javatpoint.com.sumoftwonumber.MainActivity">  

  

    <EditText  

        android:id="@+id/editText1"  

        android:layout_width="wrap_content"          

   android:layout_height="wrap_conte"  

        android:layout_alignParentTop="true"  

        android:layout_centerHorizontal="true"  

        android:layout_marginTop="61dp"  

        android:ems="10"  

        android:inputType="number"  

        tools:layout_editor_absoluteX="84dp"  

        tools:layout_editor_absoluteY="53dp" />  

  

    <EditText  

        android:id="@+id/editText2"  

        android:layout_width="wrap_content"  

        android:layout_height="wrap_content"  

        android:layout_below="@+id/editText1"  

        android:layout_centerHorizontal="true"  

        android:layout_marginTop="32dp"  

        android:ems="10"  

        android:inputType="number"  

        tools:layout_editor_absoluteX="84dp"  

        tools:layout_editor_absoluteY="127dp" />  

  

    <Button  

        android:id="@+id/button"  

        android:layout_width="wrap_content"  

        android:layout_height="wrap_content"  

        android:layout_below="@+id/editText2"  

        android:layout_centerHorizontal="true"  

        android:layout_marginTop="109dp"  

        android:text="ADD"  

        tools:layout_editor_absoluteX="148dp"  

        tools:layout_editor_absoluteY="266dp" />  

</RelativeLayout>              

Activity Class

Now write the code to display the sum of two numbers.

File: MainActivity.java

package example.javatpoint.com.sumoftwonumber;  

  

import android.support.v7.app.AppCompatActivity;  

import android.os.Bundle;  

import android.view.View;  

import android.widget.Button;  

import android.widget.EditText;  

import android.widget.Toast;  

  

public class MainActivity extends AppCompatActivity {  

    private EditText edittext1, edittext2;  

    private Button buttonSum;  

  

    @Override  

    protected void onCreate(Bundle savedInstanceState) {  

        super.onCreate(savedInstanceState);  

        setContentView(R.layout.activity_main);  

  

        addListenerOnButton();  

    }  

  

    public void addListenerOnButton() {  

        edittext1 = (EditText) findViewById(R.id.editText1);  

        edittext2 = (EditText) findViewById(R.id.editText2);  

        buttonSum = (Button) findViewById(R.id.button);  

  

        buttonSum.setOnClickListener(new View.OnClickListener() {  

            @Override  

            public void onClick(View view) {  

                String value1=edittext1.getText().toString();  

                String value2=edittext2.getText().toString();  

                int a=Integer.parseInt(value1);  

                int b=Integer.parseInt(value2);  

                int sum=a+b;  

                Toast.makeText(getApplicationContext(),String.valueOf(sum), Toast.LENGTH_LONG).show();  

            }  

        });  

    }  

}  

Out Put :-