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

Posted by wang hong
wang hong
Courses Plus Student 147 Points

hello，how can I solve this problem ?No matter how hard I try ,it can not through ,give me a hand please,thanks.

hello，how can I solve this problem ?No matter how hard I try ,it can not through ,I don't know how to solve this ,give me a hand please,thanks.

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

    }

}

2 Answers

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Let's do this!

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!

We have mExterminateButton declared in the class, we to initialize inside onCreate(). The GUI has a button called button1 that needs linking to this variable in the code. We use findViewById() to do this, casting the returned object to the required type. That's a Button in this case. 

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

That should do it!

Steve.

wang hong
wang hong
Courses Plus Student 147 Points

yes,I also write like yours,but it show me it is wrong!What happened?

Steve Hunter
Steve Hunter
57,712 Points

Let me try that again ... ?!

Steve Hunter
Steve Hunter
57,712 Points

That code does work:

http://goo.gl/QgG6yh

Can you paste your code, please?

Steve. 

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

}
wang hong
wang hong
Courses Plus Student 147 Points

Thanks,the code I have paste there.

Steve Hunter
Steve Hunter
57,712 Points

That's really strange.

I suggest you hit Ctrl+F5 to reload the challenge fully and try that code again - there seems nothing wrong with it!

wang hong
wang hong
Courses Plus Student 147 Points

ok,Thank you,if I have problem,I will ask you again.Thank you very much .

Steve Hunter
Steve Hunter
57,712 Points

Please do, yes - let's got you through this!

wang hong
PLUS
wang hong
Courses Plus Student 147 Points
wang hong
wang hong
Courses Plus Student 147 Points 
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
          mExterminateButton = (Button) findViewById(R.id.button1);
    }

}