Android Development Learning Path-log use

I have written a onkeydown function that captures the upper and lower keyboards, following a general tutorial, that is, Android primer to Mastery.

The use of the four keycode_dpad_up,, but actually did not respond. Then with the help of log in the terminal output, found the problem.

1. Import the LOG packet imports Android.util.Log first;

2. class defines a private string type private static final string tag= "KeyEvent";

3. Internal function, output

LOG.V (TAG, "onkeydown:keycode=" +keycode);
LOG.V (TAG, "onkeydown:string=" +msg.tostring ());

4. Check the Logcat file when the key is pressed while the program is running

Android Development Learning Path-log use