Android WMS--Window相关数据类

WindowManagerService主要是负责管理WindowState和窗口动画的

1:WMS有关Window相关的数据结构

WMS数据结构.png

2:RootWindowContainer

RootWindowContainer的初始化是在WMS中完成的，其主要是用来管理显示屏幕的，其关联着一组DisplayContent,设备上的所有显示 屏幕都是其来管理

WindowList<E> mChildren，E代表的是DisplayContent
protected final SurfaceAnimator mSurfaceAnimator;//窗口动画

3:DisplayContent

DisplayContent代表的是一块显示屏幕，其被RootWindowContainer所管理,该显示屏上的窗口以栈的形式管理,DisplayContent有四种类型的container,分别用来存储不同类型的窗口:应用程序窗口，系统类型的窗口，输入法窗口和壁纸窗口，在addWindowToken中来决定需要加入到哪个Container中

/** Unique identifier of this stack. */
    private final int mDisplayId;
    /** The containers below are the only child containers the display can have. */
    // Contains all window containers that are related to apps (Activities)
    private final TaskStackContainers mTaskStackContainers = new TaskStackContainers(mService);
    // Contains all non-app window containers that should be displayed above the app containers
    // (e.g. Status bar)
    private final AboveAppWindowContainers mAboveAppWindowsContainers =
            new AboveAppWindowContainers("mAboveAppWindowsContainers", mService);
    // Contains all non-app window containers that should be displayed below the app containers
    // (e.g. Wallpaper).
    private final NonAppWindowContainers mBelowAppWindowsContainers =
            new NonAppWindowContainers("mBelowAppWindowsContainers", mService);
    // Contains all IME window containers. Note that the z-ordering of the IME windows will depend
    // on the IME target. We mainly have this container grouping so we can keep track of all the IME
    // window containers together and move them in-sync if/when needed. We use a subclass of
    // WindowContainer which is omitted from screen magnification, as the IME is never magnified.
    private final NonMagnifiableWindowContainers mImeWindowsContainers =
            new NonMagnifiableWindowContainers("mImeWindowsContainers", mService);
 // Mapping from a token IBinder to a WindowToken object on this display.
    private final HashMap<IBinder, WindowToken> mTokenMap = new HashMap();

4:TaskStack

用来管理Window的，形式就是栈的形式,对应AMS端的ActivityStack

   /** Unique identifier */
    final int mStackId;
    /** The display this stack sits under. */
    // TODO: Track parent marks like this in WindowContainer.
    private DisplayContent mDisplayContent;
    /** Application tokens that are exiting, but still on screen for animations. */
    final AppTokenList mExitingAppTokens = new AppTokenList();
    final AppTokenList mTmpAppTokens = new AppTokenList();

5:Task

Task可以理解成一个任务栈，用来管理AppWindowToken的，对应AMS端的TaskRecord

 TaskStack mStack;
 final int mTaskId;
 final int mUserId;
 //表明Task关联着一组AppWindowToken,WindowList<E> mChildren表示的是WindowList<AppWindowToken> mChildRen
 class Task extends WindowContainer<AppWindowToken>

6:AppWindowToken

AppWindowToken关联着一组有相同Token值的WindowState,WindowState并不是和Activity一一对应的，因为窗口有子窗口，系统窗口，应用程序窗口三种，子窗口和应用程序窗口共用相同的token值

 // Non-null only for application tokens.
 final IApplicationToken appToken;
 WindowList<WindowState> mChildren;存储的所有的WindowState

7:WindowState

WindowState代表是WMS端的窗口对象，WindowState是应用程序通过WindowManager.addView创建的，WindowState是有层级的，其层级是有layer来决定，最终是由窗口类型来决定的

 final Session mSession;
 final IWindow mClient;
 final WindowId mWindowId;
 WindowToken mToken;
 // The same object as mToken if this is an app window and null for non-app windows.
 AppWindowToken mAppToken;
 final int mBaseLayer;//baselayer
 final int mSubLayer;//sublayer
 final boolean mLayoutAttached;
 final boolean mIsImWindow;//输入法窗口
 final boolean mIsWallpaper;//壁纸窗口
 final WindowManager.LayoutParams mAttrs//窗口属性