Android7.0 Notification控制

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

当有通知过来的时候就会走这里，如果想invalid所以通知就在这里做。

@Override
public void onNotificationPosted(final StatusBarNotification sbn,
        final RankingMap rankingMap) {
    if (DEBUG) Log.d(TAG, "onNotificationPosted: " + sbn);
    if (sbn != null) {
        mHandler.post(new Runnable() {
            @Override
            public void run() {
                processForRemoteInput(sbn.getNotification());
                String key = sbn.getKey();
                mKeysKeptForRemoteInput.remove(key);
                boolean isUpdate = mNotificationData.get(key) != null;
                // In case we don't allow child notifications, we ignore children of
                // notifications that have a summary, since we're not going to show them
                // anyway. This is true also when the summary is canceled,
                // because children are automatically canceled by NoMan in that case.
                if (!ENABLE_CHILD_NOTIFICATIONS  && mGroupManager.isChildInGroupWithSummary(sbn)) {
                    if (DEBUG) {
                        Log.d(TAG, "Ignoring group child due to existing summary: " + sbn);
                    }

                    // Remove existing notification to avoid stale data.
                    if (isUpdate) {
                        removeNotification(key, rankingMap);
                    } else {
                        mNotificationData.updateRanking(rankingMap);
                    }
                    return;
                }
                if (isUpdate) {
                    updateNotification(sbn, rankingMap);
                } else {
                    addNotification(sbn, rankingMap, null /* oldEntry */);
                }
            }
        });
    }
}