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Android Build an Interactive Story App (Retired) Intents and Multiple Activities Starting a New Activity

setOnClickListener() , View.onClickListener() , View datatype.

What does setOnClickListener() , View.onClickListener() mean?? explain me briefly what does "View" datatype really mean in java programming?? why do we write LaunchActivity extends Activity??

LaunchActivity.java
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class LaunchActivity extends Activity {

  public Button mLaunchButton;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_launch);

    mLaunchButton = (Button)findViewById(R.id.launchButton);
    mLaunchButton.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        // Add your code in here!
        Intent 
      }
    });
  }
}

1 Answer

Views are specific to android development and are just Objects. View is the super class(or Parent class) that all other child class views( like Button, TextView, ImageView) inherit from. Having a View class and its child classes also allows you to interact with your UI inside of your java code. LaunchActivity extends Activity is an example of setting up that inheritance. What you are telling your compiler in that line is that you want all the functionality that Activity has to be available to LaunchActivity.

what about setOnClickListener()??