A encapsulated popup window which show given content view(mostly menus).

gistfile1.java

/**
 * 
 * @author viyu
 * 
 */
public class MenuPopWindow extends PopupWindow implements OnClickListener {

	private Activity mActivity = null;
	private CustomView mContentView = null;
	private TextView mItemQuit = null;
	//
	public MenuPopWindow(Activity activity) {
		super(activity);
		mActivity = activity;
		initUI();
	}

	protected MenuPopWindow(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	private void initUI() {
		LayoutInflater mInflater = mActivity.getLayoutInflater();
		mContentView = (CustomView) mInflater.inflate(R.layout.menu_pop_window, null);
		//如果要用menu键来控制window，可以注册这个
		mContentView.setKeyEventCallback(new KeyEventCallback() {
			@Override
			public void onMenuKeyDown() {
				showPopWindow(....);
			}
		});
		setContentView(mContentView);
		//
		mItemQuit = (TextView) mContentView.findViewById(R.id.menu_pop_window_quit);
		mItemQuit.setOnClickListener(this);
		//
		setOutsideTouchable(true);
		setFocusable(true);
		//
		mContentView.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
		setWidth(mContentView.getMeasuredWidth());
		setHeight(mContentView.getMeasuredHeight());
		//
		setBackgroundDrawable(...);
	}

	@Override
	public void onClick(View v) {
		if (v == mItemQuit) {
			 ...
		}
		dismiss();
	}

 	public void showPopWindow(View mHostView, xOff, yOff) {
		//
		if (isShowing()) {
			dismiss();
			return;
		}
		//
		showAsDropDown(mHostView, xOff, yOff);
	}
}

gistfile2.java

/**
 * 
 * @author viyu
 * 
 */
public class CustomView extends LinearLayout {

	private KeyEventCallback mKeyEventCallback = null;

	public CustomView(Context context) {
		super(context);
		setFocusableInTouchMode(true);
	}

	public CustomView(Context context, AttributeSet attrs) {
		super(context, attrs);
		setFocusableInTouchMode(true);
	}

	public void setKeyEventCallback(KeyEventCallback keyEventCallback) {
		mKeyEventCallback = keyEventCallback;
	}

	@Override
	public boolean dispatchKeyEvent(KeyEvent event) {
		if (event.getAction() == KeyEvent.ACTION_DOWN && event.getKeyCode() == KeyEvent.KEYCODE_MENU) {
			if (mKeyEventCallback != null) {
				mKeyEventCallback.onMenuKeyDown();
			}
		}
		return super.dispatchKeyEvent(event);
	}

	public interface KeyEventCallback {
		public void onMenuKeyDown();
	}
}