【Android 7.1.1】 锁屏界面点击“空白处”响应事件

frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/stack/NotificationStackScrollLayout.java

frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationPanelView.java

frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/PanelView.java

1. NotificationStackScrollLayout.java

2.NotificationPanelView.java

@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;
        }
    }

3.PanelView.java