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Android Build an Interactive Story App (Retired) User Input Finding Views by IDs

Sonya Cook
Sonya Cook
1,307 Points
Posted by Sonya Cook
Sonya Cook
1,307 Points

Help needed: Challenge Task 1

Having problems with this challenge

MainActivity.java 
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {

    protected Button mExterminateButton;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Declare our view variables

    }

}

1 Answer

Christopher Augg
Christopher Augg
21,223 Points
Christopher Augg
Christopher Augg
21,223 Points

Hello Sonya,

I always like to break down the instructions to get a good understanding of what I need to do for a challenge:

Initialize the member variable mExterminateButton using the findViewById() method. The ID for the button is button1. Don't forget to cast the generic View returned by the method!

  • Initialize mExterminateButton using findViewById() method.
  • The id for the button is button1. We need to pass R.id.button1 into the findViewById() method.
  • We need to cast the generic view we get from calling the findViewById() to a Button in order to assign it to mExterminateButton.

mExterminateButton = (Button) findViewById(R.id.button1);

As you can see, we are calling the findViewById method and passing it R.id.button1. This returns a generic view based on that id. Therefore, we cast it using (Button) to assign it to mExterminateButton.

Remember, the R class is dynamically generated during the build process. It provides a link to the resources like Strings, android widgets, graphics, and layouts. You can check this out to get a better understanding.

Hope this helps.

Regards,

Chris