OnClickListener interface in Android

Question

I am new to programming, I have very basic knowledge in android. As I learned in java that an Interface cannot be instantiated And that new is a keyword in Java that indicates creating an instance. I came across following code in Android:

public class MyActivity extends Activity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);

    setContentView(R.layout.mylayout);
    findViewById(R.id.button1).setOnClickListener(mButton1_OnClickListener);
  }  

  //On click listener for button1
  final OnClickListener mButton1_OnClickListener = new OnClickListener() {
    public void onClick(final View v) {
        //Inform the user the button has been clicked
        Toast.makeText(this, "Button1 clicked.", Toast.LENGTH_SHORT).show();               
    }
  };
}

Above code OnClickListener is a public interface and onClick(final View v) is an abstract method, Here goes my question: OnClickListener being an interface, how is possible to create an instance of it by using the new keyword in the example above?

Answer 1

Here you are not instantiating an interface you are doing by Anonymous inner class.Your are not creating the object of the interface .you are creating this for the Anonymous class which is you gonna create in next step inside {Anonymous inner class};.If want to know more details of this you have to through Anonymous inner class.

Check it out below links:

http://c2.com/cgi/wiki?AnonymousInnerClass

http://docs.oracle.com/javase/tutorial/java/javaOO/anonymousclasses.html