@Override

    protected boolean onMiddleClicked() {

        switch (mStatusBar.getBarState()) {

            case StatusBarState.KEYGUARD:

                if (!mDozingOnDown) {

                    EventLogTags.writeSysuiLockscreenGesture(

                            EventLogConstants.SYSUI_LOCKSCREEN_GESTURE_TAP_UNLOCK_HINT,

                            0 /* lengthDp - N/A */, 0 /* velocityDp - N/A */);

                    startUnlockHintAnimation();

                }

                return true;

            case StatusBarState.SHADE_LOCKED:

                if (!mQsExpanded) {

                    mStatusBar.goToKeyguard();

                }

                return true;

            case StatusBarState.SHADE:

                // This gets called in the middle of the touch handling, where the state is still

                // that we are tracking the panel. Collapse the panel after this is done.

                //wtrom,zhaoxiaohui,20170221,for drop down menu

                if(!isSupportWTRom){

                    post(mPostCollapseRunnable);

                }

                return false;

            default:

                return true;

        }

    }