android4.0 支持监控鼠标事件hover

public class HoverDemoActivity extends Activity {
    private Button btnBottom;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        btnBottom = (Button) findViewById(R.id.btn_bottom);

        btnBottom.setOnHoverListener(new OnHoverListener() {
            @Override
            public boolean onHover(View v, MotionEvent event) {
                int what = event.getAction();
                switch(what){
                 case MotionEvent.ACTION_HOVER_ENTER: //鼠标进入view
                     System.out.println("bottom ACTION_HOVER_ENTER");
                     break;
                 case MotionEvent.ACTION_HOVER_MOVE: //鼠标在view上
                     System.out.println("bottom ACTION_HOVER_MOVE");
                     break;
                 case MotionEvent.ACTION_HOVER_EXIT: //鼠标离开view
                     System.out.println("bottom ACTION_HOVER_EXIT");
                     break;
                }
                return false;
            }
        });
    }
}