Question

I want to be able to detect a single click or a double click when the menu button is pressed. If a single click is detected one even will happen, if a double click is detected a different event will happen. Here is what I’ve tried(Using toast in place of events):

private static final long DOUBLE_PRESS_INTERVAL = 250; // in millis
private long lastPressTime;

@Override
public boolean onPrepareOptionsMenu(Menu menu) {    

    // Get current time in nano seconds.
    long pressTime = System.currentTimeMillis();


    // If double click...
    if (pressTime - lastPressTime <= DOUBLE_PRESS_INTERVAL) {
        Toast.makeText(getApplicationContext(), "Double Click Event", Toast.LENGTH_SHORT).show();
        return true;
    }

    // If not double click....
    Toast.makeText(getApplicationContext(), "Single Click Event", Toast.LENGTH_SHORT).show();

    // record the last time the menu button was pressed.
    lastPressTime = pressTime;      
    return true;
}

The problem is that a single click event is detected every time before a double click event.

Answer 1

Simple logic mistake. You are returning before recording the new lastPressTime. You should only have one return call if they are both returning the same thing:

boolean mHasDoubleClicked = false;

    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {    

        // Get current time in nano seconds.
        long pressTime = System.currentTimeMillis();


        // If double click...
        if (pressTime - lastPressTime <= DOUBLE_PRESS_INTERVAL) {
            Toast.makeText(getApplicationContext(), "Double Click Event", Toast.LENGTH_SHORT).show();
            mHasDoubleClicked = true;
        }
        else {     // If not double click....
            mHasDoubleClicked = false;
            Handler myHandler = new Handler() {
                 public void handleMessage(Message m) {
                      if (!mHasDoubleClicked) {
                            Toast.makeText(getApplicationContext(), "Single Click Event", Toast.LENGTH_SHORT).show();
                      }
                 }
            };
            Message m = new Message();
            myHandler.sendMessageDelayed(m,DOUBLE_PRESS_INTERVAL);
        }
        // record the last time the menu button was pressed.
        lastPressTime = pressTime;      
        return true;
    }