Question

I am newbie android, I study android by work with demo code, here is my code:

public class MainActivity extends Activity {

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        TextView txt = (TextView) findViewById(R.id.txtHello);
        txt.setText("Hello World!");
    }
}

And here is XML file :

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
    android:id="@+id/txtHello"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />
</LinearLayout>

But when I run this project, I cannot see this textview, everyone help me please :(, I do not know my problem is..?

Answer 1

The solution seems to be easy.

• Move your mouse pointer over the green lock
• Press and hold mouse button
• Move your mouse while holing the left button, until the green lock reaches the orange circle.
• If you pressed the green play button in Eclipse, your app will show up under the Screen you see now. (called Lock Screen)

Not to be rude, but it’s better to start learning Android on http://developer.android.com . You will find it really useful, especially the http://developer.android.com/training/index.html part.