本文主要是介绍Android8.1 MTK平台 SystemUI源码分析之 Notification流程，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
流程图
代码流程
1、先看UI显示，StatuBar加载 CollapsedStatusBarFragment 替换 status_bar_container(状态栏通知显示区域)
SystemUI\src\com\android\systemui\statusbar\phone\StatusBar.java
FragmentHostManager.get(mStatusBarWindow).addTagListener(CollapsedStatusBarFragment.TAG, (tag, fragment) -> {CollapsedStatusBarFragment statusBarFragment =(CollapsedStatusBarFragment) fragment;statusBarFragment.initNotificationIconArea(mNotificationIconAreaController);mStatusBarView = (PhoneStatusBarView) fragment.getView();mStatusBarView.setBar(this);mStatusBarView.setPanel(mNotificationPanel);mStatusBarView.setScrimController(mScrimController);mStatusBarView.setBouncerShowing(mBouncerShowing);setAreThereNotifications();checkBarModes();/// M: add for plmn display feature @{attachPlmnPlugin();///@}}).getFragmentManager().beginTransaction().replace(R.id.status_bar_container, new CollapsedStatusBarFragment(),CollapsedStatusBarFragment.TAG).commit();
statusBarFragment.initNotificationIconArea(mNotificationIconAreaController) 初始化通知栏区域，这是我们关心的
mStatusBarView.setBar(this) 传递statusBar处理下拉事件
mStatusBarView.setPanel(mNotificationPanel) 传递 NotificationPanelView 显示下拉UI控制
2、跟进 CollapsedStatusBarFragment 中，先看布局文件 status_bar.xml
1、notification_lights_out---ImageView默认gone2、status_bar_contents--LinearLayoutnotification_icon_area--FrameLayoutsystem_icon_area--LinearLayoutsystem_icons.xml(蓝牙、wifi、VPN、网卡、SIM卡信号、飞行模式等) 电池clock--Clock.java 3、emergency_cryptkeeper_text--ViewStub（延迟加载 紧急电话文字）
这就是我们看到的statusBar的布局，本篇只关心 notification_icon_area，其它的以后再进行分析。继续看到之前的 initNotificationIconArea()
SystemUI\src\com\android\systemui\statusbar\phone\CollapsedStatusBarFragment.java
public void initNotificationIconArea(NotificationIconAreaControllernotificationIconAreaController) {ViewGroup notificationIconArea = mStatusBar.findViewById(R.id.notification_icon_area);mNotificationIconAreaInner =notificationIconAreaController.getNotificationInnerAreaView();if (mNotificationIconAreaInner.getParent() != null) {((ViewGroup) mNotificationIconAreaInner.getParent()).removeView(mNotificationIconAreaInner);}notificationIconArea.addView(mNotificationIconAreaInner);// Default to showing until we know otherwise.showNotificationIconArea(false);
}
获取到 notification_icon_area，FrameLayout转为ViewGroup，调用 notificationIconAreaController 获取通知要显示的view(LinearLayout)，
如果已经有显示的view，通过 view 父布局将其自身remove，然后再重新addView。最后将 mNotificationIconAreaInner 显示出来(设置透明度为1，visibility为VISIBLE)
可以看到 CollapsedStatusBarFragment 中定义了几个如下的方法。
public void hideSystemIconArea(boolean animate) {animateHide(mSystemIconArea, animate);
}public void showSystemIconArea(boolean animate) {animateShow(mSystemIconArea, animate);
}public void hideNotificationIconArea(boolean animate) {animateHide(mNotificationIconAreaInner, animate);
}public void showNotificationIconArea(boolean animate) {animateShow(mNotificationIconAreaInner, animate);
}
当状态栏下拉时，状态栏中的图标icon会慢慢的变成透明和不可见，就是通过hideSystemIconArea(true), hideNotificationIconArea(true）
3、接下来，我们需要跟进 getNotificationInnerAreaView()方法中看看通知栏icon对应的容器
SystemUI\src\com\android\systemui\statusbar\phone\NotificationIconAreaController.java
public View getNotificationInnerAreaView() {return mNotificationIconArea;
}protected void initializeNotificationAreaViews(Context context) {reloadDimens(context);LayoutInflater layoutInflater = LayoutInflater.from(context);mNotificationIconArea = inflateIconArea(layoutInflater);mNotificationIcons = (NotificationIconContainer) mNotificationIconArea.findViewById(R.id.notificationIcons);mNotificationScrollLayout = mStatusBar.getNotificationScrollLayout();
}protected View inflateIconArea(LayoutInflater inflater) {return inflater.inflate(R.layout.notification_icon_area, null);
}//notification_icon_area.xml
<com.android.keyguard.AlphaOptimizedLinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/notification_icon_area_inner"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<com.android.systemui.statusbar.phone.NotificationIconContainerandroid:id="@+id/notificationIcons"android:layout_width="match_parent"android:layout_height="match_parent"android:layout_alignParentStart="true"android:gravity="center_vertical"android:orientation="horizontal"/>
</com.android.keyguard.AlphaOptimizedLinearLayout>
好了，观察上面的代码，现在基本上已经理清 notification_icon_area 的布局结构了
notification_icon_area(FrameLayout) 中添加 notification_icon_area_inner(LinearLayout),
每一个通知对应的bean为 NotificationData，创建 Notification 添加到 NotificationIconContainer(FrameLayout)中
4、紧接着我们就来看下 Notification 的监听加载流程，回到 statusBar 的start()中注册 NotificationListenerWithPlugins 作为系统service监听通知消息
try {mNotificationListener.registerAsSystemService(mContext,new ComponentName(mContext.getPackageName(), getClass().getCanonicalName()),UserHandle.USER_ALL);} catch (RemoteException e) {Log.e(TAG, "Unable to register notification listener", e);}private final NotificationListenerWithPlugins mNotificationListener =new NotificationListenerWithPlugins() {@Overridepublic void onListenerConnected() {...... services成功启动，获取当前处于活动状态的通知(没被移除的通知)，添加到通知栏，此处应该是重启后重新加载}@Overridepublic void onNotificationPosted(final StatusBarNotification sbn,final RankingMap rankingMap) {...... 收到通知消息，添加或者修改if (isUpdate) {updateNotification(sbn, rankingMap);} else {addNotification(sbn, rankingMap);}}@Overridepublic void onNotificationRemoved(StatusBarNotification sbn,final RankingMap rankingMap) {...... 移除通知消息if (sbn != null && !onPluginNotificationRemoved(sbn, rankingMap)) {final String key = sbn.getKey();mHandler.post(() -> removeNotification(key, rankingMap));}}@Overridepublic void onNotificationRankingUpdate(final RankingMap rankingMap) {..... 通知的排序优先级改变，修改通知位置if (rankingMap != null) {RankingMap r = onPluginRankingUpdate(rankingMap);mHandler.post(() -> updateNotificationRanking(r));}}};
继续来看下 addNotification()方法
public void addNotification(StatusBarNotification notification, RankingMap ranking)throws InflationException {String key = notification.getKey();if (true/**DEBUG*/) Log.d(TAG, "addNotification key=" + key);mNotificationData.updateRanking(ranking);Entry shadeEntry = createNotificationViews(notification);......
}
可以看到是通过 createNotificationViews()来创建通知 View对象，内部继续调用 inflateViews()
protected NotificationData.Entry createNotificationViews(StatusBarNotification sbn)throws InflationException {if (DEBUG) {Log.d(TAG, "createNotificationViews(notification=" + sbn);}NotificationData.Entry entry = new NotificationData.Entry(sbn);Dependency.get(LeakDetector.class).trackInstance(entry);entry.createIcons(mContext, sbn);// Construct the expanded view.inflateViews(entry, mStackScroller);return entry;
}protected void inflateViews(Entry entry, ViewGroup parent) {PackageManager pmUser = getPackageManagerForUser(mContext,entry.notification.getUser().getIdentifier());final StatusBarNotification sbn = entry.notification;if (entry.row != null) {entry.reset();updateNotification(entry, pmUser, sbn, entry.row);} else {new RowInflaterTask().inflate(mContext, parent, entry,row -> {bindRow(entry, pmUser, sbn, row);updateNotification(entry, pmUser, sbn, row);});}}
看到上面的方法中，entry在 createNotificationViews 中创建，只赋值了icons， entry.row 为null，进入 RowInflaterTask 中
SystemUI\src\com\android\systemui\statusbar\notification\RowInflaterTask.java
public void inflate(Context context, ViewGroup parent, NotificationData.Entry entry,RowInflationFinishedListener listener) {mListener = listener;AsyncLayoutInflater inflater = new AsyncLayoutInflater(context);mEntry = entry;entry.setInflationTask(this);inflater.inflate(R.layout.status_bar_notification_row, parent, this);
}
这里我们得到了 Notification 对应的layout为 status_bar_notification_row.xml，
回调方法中将 row 和 entry 绑定，继续再调用 updateNotification()，注意这个方法是四个参数的，该类中还有重载方法是两个参数的。
private void updateNotification(Entry entry, PackageManager pmUser,StatusBarNotification sbn, ExpandableNotificationRow row) {.....entry.row = row;entry.row.setOnActivatedListener(this);boolean useIncreasedCollapsedHeight = mMessagingUtil.isImportantMessaging(sbn,mNotificationData.getImportance(sbn.getKey()));boolean useIncreasedHeadsUp = useIncreasedCollapsedHeight && mPanelExpanded;row.setUseIncreasedCollapsedHeight(useIncreasedCollapsedHeight);row.setUseIncreasedHeadsUpHeight(useIncreasedHeadsUp);row.updateNotification(entry);
}
紧接着调用了 ExpandableNotificationRow的 updateNotification()，内部继续调用 NotificationInflater.inflateNotificationViews()
SystemUI\src\com\android\systemui\statusbar\notification\NotificationInflater.java
@VisibleForTesting
void inflateNotificationViews(int reInflateFlags) {if (mRow.isRemoved()) {// We don't want to reinflate anything for removed notifications. Otherwise views might// be readded to the stack, leading to leaks. This may happen with low-priority groups// where the removal of already removed children can lead to a reinflation.return;}StatusBarNotification sbn = mRow.getEntry().notification;new AsyncInflationTask(sbn, reInflateFlags, mRow, mIsLowPriority,mIsChildInGroup, mUsesIncreasedHeight, mUsesIncreasedHeadsUpHeight, mRedactAmbient,mCallback, mRemoteViewClickHandler).execute();
}
new AsyncInflationTask().execute();
@Override
protected InflationProgress doInBackground(Void... params) {try {final Notification.Builder recoveredBuilder= Notification.Builder.recoverBuilder(mContext,mSbn.getNotification());Context packageContext = mSbn.getPackageContext(mContext);Notification notification = mSbn.getNotification();if (mIsLowPriority) {int backgroundColor = mContext.getColor(R.color.notification_material_background_low_priority_color);recoveredBuilder.setBackgroundColorHint(backgroundColor);}if (notification.isMediaNotification()) {MediaNotificationProcessor processor = new MediaNotificationProcessor(mContext,packageContext);processor.setIsLowPriority(mIsLowPriority);processor.processNotification(notification, recoveredBuilder);}return createRemoteViews(mReInflateFlags,recoveredBuilder, mIsLowPriority, mIsChildInGroup,mUsesIncreasedHeight, mUsesIncreasedHeadsUpHeight, mRedactAmbient,packageContext);} catch (Exception e) {mError = e;return null;}
}@Override
protected void onPostExecute(InflationProgress result) {if (mError == null) {mCancellationSignal = apply(result, mReInflateFlags, mRow, mRedactAmbient,mRemoteViewClickHandler, this);} else {handleError(mError);}
}
从msbn中获取 notifaction，判断是否是媒体类型的通知，进行对应的主题背景色修改，通过传递的优先级设置通知背景色，继续看核心方法 createRemoteViews()
private static InflationProgress createRemoteViews(int reInflateFlags,Notification.Builder builder, boolean isLowPriority, boolean isChildInGroup,boolean usesIncreasedHeight, boolean usesIncreasedHeadsUpHeight, boolean redactAmbient,Context packageContext) {InflationProgress result = new InflationProgress();isLowPriority = isLowPriority && !isChildInGroup;if ((reInflateFlags & FLAG_REINFLATE_CONTENT_VIEW) != 0) {result.newContentView = createContentView(builder, isLowPriority, usesIncreasedHeight);}if ((reInflateFlags & FLAG_REINFLATE_EXPANDED_VIEW) != 0) {result.newExpandedView = createExpandedView(builder, isLowPriority);}if ((reInflateFlags & FLAG_REINFLATE_HEADS_UP_VIEW) != 0) {result.newHeadsUpView = builder.createHeadsUpContentView(usesIncreasedHeadsUpHeight);}if ((reInflateFlags & FLAG_REINFLATE_PUBLIC_VIEW) != 0) {result.newPublicView = builder.makePublicContentView();}if ((reInflateFlags & FLAG_REINFLATE_AMBIENT_VIEW) != 0) {result.newAmbientView = redactAmbient ? builder.makePublicAmbientNotification(): builder.makeAmbientNotification();}result.packageContext = packageContext;return result;
}
这里就是创建各种布局 CONTENT_VIEW、EXPANDED_VIEW、HEADS_UP_VIEW、PUBLIC_VIEW、AMBIENT_VIEW，
然后回到 AsyncInflationTask 的 onPostExecute()中执行 apply(),代码太多就不贴了, SystemUI部分的通知流程分析技术，欢迎留言讨论。
statusBar左边区域(notification_icon_area)看完了，接下来看下右边的系统图标区域(system_icon_area)
Android8.1 SystemUI源码分析之 电池时钟刷新
从根源上屏蔽Notification
frameworks/base/services/core/java/com/android/server/notification/NotificationManagerService.java
注释如下代码
mHandler.post(new EnqueueNotificationRunnable(userId, r))
这篇关于Android8.1 MTK平台 SystemUI源码分析之 Notification流程的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
