How to make a phone call on clicking a button in android

In some of the apps that we develop we may need to make a call through it. This could easily be done by using implicit Intent with appropriate actions.We can use Android Intent to make phone call by calling built-in Phone Call functionality of the Android.In my code i will be using ACTION_DIAL where we will be having option to modify hard coded phone number before making a call instead of making direct call.

Intent callIntent = new Intent(Intent.ACTION_DIAL, number);

Following code snippet shows  how to use Android Intent to make phone call to the given mobile number.

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Button callbutton = (Button) findViewById(R.id.callbtn);
    callbutton.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {

        Uri number = Uri.parse("tel:0123456789");
        Intent callIntent = new Intent(Intent.ACTION_DIAL, number);

        startActivity(callIntent);
    }

});
}

We need to add the following button code in xml:
<Button
    android:id="@+id/callbtn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginLeft="50dp"
    android:layout_marginTop="130dp"
    android:text="0123456789"
    />