Android6.0 WMS（四） WMS中常用变量分析

这篇博客我们分析WMS的一些常用变量，我们依然从主线addWindow开始分析，碰到一些常用的变量再进行分析。

DisplayContent

我们再来看如下DisplayContent 类

            final DisplayContent displayContent = getDisplayContentLocked(displayId);

我们再来看getDisplayContentLocked函数，当mDisplayContents没有对应displayId对应的DisplayContent，会调用newDisplayContentLocked函数创建一个DisplayContent 然后放入mDisplayContents。

    public DisplayContent getDisplayContentLocked(final int displayId) {
        DisplayContent displayContent = mDisplayContents.get(displayId);
        if (displayContent == null) {
            final Display display = mDisplayManager.getDisplay(displayId);
            if (display != null) {
                displayContent = newDisplayContentLocked(display);
            }
        }
        return displayContent;
    }

DisplayContent 的mWindows放了该显示设备所有的window。

WindowManager.LayoutParams  token

我们看addWindow这个函数的一个参数WindowManager.LayoutParams attrs，这个参数有很多地方修改，最基本的是在Activity应用中调用setContentView的时候会初始化。

现在我们来看其中一个重要的成员变量token。

先看下面代码，当该窗口是一个子窗口时，会调用windowForClientLocked来查找主窗口的WindowState。这个WindowState也就是子窗口的attachedWindow。

            if (type >= FIRST_SUB_WINDOW && type <= LAST_SUB_WINDOW) {
                attachedWindow = windowForClientLocked(null, attrs.token, false);
                if (attachedWindow == null) {
                    Slog.w(TAG, "Attempted to add window with token that is not a window: "
                          + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_SUBWINDOW_TOKEN;
                }
                if (attachedWindow.mAttrs.type >= FIRST_SUB_WINDOW
                        && attachedWindow.mAttrs.type <= LAST_SUB_WINDOW) {
                    Slog.w(TAG, "Attempted to add window with token that is a sub-window: "
                            + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_SUBWINDOW_TOKEN;
                }
            }

我们来看下windowForClientLocked函数，就是从mWindowMap中获取其attrs.token的WindowState，说明子窗口的attrs.token放的是其父窗口的token。

    final WindowState windowForClientLocked(Session session, IBinder client,
            boolean throwOnError) {
        WindowState win = mWindowMap.get(client);
        ......

        return win;
    }

那我们先来看看这个token是从何而来，

我们知道WMS的addWindow，是用ActivityThread的handleResumeActivity函数调用如下代码发起的，我们先来看看WindowManagerImpl的addView函数

            if (r.window == null && !a.mFinished && willBeVisible) {
                r.window = r.activity.getWindow();
                View decor = r.window.getDecorView();
                decor.setVisibility(View.INVISIBLE);
                ViewManager wm = a.getWindowManager();
                WindowManager.LayoutParams l = r.window.getAttributes();
                a.mDecor = decor;
                l.type = WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
                l.softInputMode |= forwardBit;
                if (a.mVisibleFromClient) {
                    a.mWindowAdded = true;
                    wm.addView(decor, l);
                }

WindowManagerImpl的addView函数，直接调用了WindowMangerGlobal的addView函数

    @Override
    public void addView(@NonNull View view, @NonNull ViewGroup.LayoutParams params) {
        applyDefaultToken(params);
        mGlobal.addView(view, params, mDisplay, mParentWindow);
    }

WindowMangerGlobal的addView函数先调用了其parentWindow的adjustLayoutParamsForSubWindow函数，然后就是创建ViewRooImpl对象，再调用其setView函数，就是在这个函数中通过Binder调用了WMS的addWindow函数。

    public void addView(View view, ViewGroup.LayoutParams params,
            Display display, Window parentWindow) {
        if (view == null) {
            throw new IllegalArgumentException("view must not be null");
        }
        if (display == null) {
            throw new IllegalArgumentException("display must not be null");
        }
        if (!(params instanceof WindowManager.LayoutParams)) {
            throw new IllegalArgumentException("Params must be WindowManager.LayoutParams");
        }

        final WindowManager.LayoutParams wparams = (WindowManager.LayoutParams) params;
        if (parentWindow != null) {
            parentWindow.adjustLayoutParamsForSubWindow(wparams);
        }
        ......
        
            root = new ViewRootImpl(view.getContext(), display);

            view.setLayoutParams(wparams);

            mViews.add(view);
            mRoots.add(root);
            mParams.add(wparams);
        }

        // do this last because it fires off messages to start doing things
        try {
            root.setView(view, wparams, panelParentView);
        } 
        ......
    }

那我们先要看这个parentWindow是谁，这个parentWindow是在创建WindowManagerImpl 时传进来的。

    public WindowManagerImpl createLocalWindowManager(Window parentWindow) {
        return new WindowManagerImpl(mDisplay, parentWindow);
    }

这个函数是在Activity的attach中调用的，代码如下：

        mWindow.setWindowManager(
                (WindowManager)context.getSystemService(Context.WINDOW_SERVICE),
                mToken, mComponent.flattenToString(),
                (info.flags & ActivityInfo.FLAG_HARDWARE_ACCELERATED) != 0);

最后我们看传参是this，就是代表Activity中创建的PhoneWindow对象。

    public void setWindowManager(WindowManager wm, IBinder appToken, String appName,
            boolean hardwareAccelerated) {
        mAppToken = appToken;
        mAppName = appName;
        mHardwareAccelerated = hardwareAccelerated
                || SystemProperties.getBoolean(PROPERTY_HARDWARE_UI, false);
        if (wm == null) {
            wm = (WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE);
        }
        mWindowManager = ((WindowManagerImpl)wm).createLocalWindowManager(this);
    }

Window的adjustLayoutParamsForSubWindow函数如下，会把wp的token改成mAppToken。

    void adjustLayoutParamsForSubWindow(WindowManager.LayoutParams wp) {
        CharSequence curTitle = wp.getTitle();
        if (wp.type >= WindowManager.LayoutParams.FIRST_SUB_WINDOW &&
           ......
        } else if (wp.type >= WindowManager.LayoutParams.FIRST_SYSTEM_WINDOW &&
           .......
        } else {
            if (wp.token == null) {
                wp.token = mContainer == null ? mAppToken : mContainer.mAppToken;
            }
            if ((curTitle == null || curTitle.length() == 0)
                    && mAppName != null) {
                wp.setTitle(mAppName);
            }
        }
        if (wp.packageName == null) {
            wp.packageName = mContext.getPackageName();
        }
        if (mHardwareAccelerated) {
            wp.flags |= WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED;
        }
    }

而这个mAppToken就是在setWindowManager时赋值的，因此这个token就是Activity的mToken。就是每一个Activity的全局唯一性。

    public void setWindowManager(WindowManager wm, IBinder appToken, String appName,
            boolean hardwareAccelerated) {
        mAppToken = appToken;
        mAppName = appName;
        mHardwareAccelerated = hardwareAccelerated
                || SystemProperties.getBoolean(PROPERTY_HARDWARE_UI, false);
        if (wm == null) {
            wm = (WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE);
        }
        mWindowManager = ((WindowManagerImpl)wm).createLocalWindowManager(this);
    }

mTokenMap

我们再回想之前分析的博客，每个Activity启动的时候会在ActivityStack中调用mWindowManager.addAppToken函数，WMS的addAppToken函数如下，就是放入mTokenMap中，key就是appToken，Value就是APPWindowToken。

    @Override
    public void addAppToken(int addPos, IApplicationToken token, int taskId, int stackId,
            int requestedOrientation, boolean fullscreen, boolean showForAllUsers, int userId,
            int configChanges, boolean voiceInteraction, boolean launchTaskBehind) {
        ......

        synchronized(mWindowMap) {
            AppWindowToken atoken = findAppWindowToken(token.asBinder());
            if (atoken != null) {
                Slog.w(TAG, "Attempted to add existing app token: " + token);
                return;
            }
            atoken = new AppWindowToken(this, token, voiceInteraction);
            ......

            mTokenMap.put(token.asBinder(), atoken);

            // Application tokens start out hidden.
            atoken.hidden = true;
            atoken.hiddenRequested = true;

        }
    }

继续回到addWindow函数，下面是一些出错处理。首先就是传来的appToken一定要在mTokenMap有对应的WindowToken。

            WindowToken token = mTokenMap.get(attrs.token);
            if (token == null) {
                if (type >= FIRST_APPLICATION_WINDOW && type <= LAST_APPLICATION_WINDOW) {
                    Slog.w(TAG, "Attempted to add application window with unknown token "
                          + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
                if (type == TYPE_INPUT_METHOD) {
                    Slog.w(TAG, "Attempted to add input method window with unknown token "
                          + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
                if (type == TYPE_VOICE_INTERACTION) {
                    Slog.w(TAG, "Attempted to add voice interaction window with unknown token "
                          + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
                if (type == TYPE_WALLPAPER) {
                    Slog.w(TAG, "Attempted to add wallpaper window with unknown token "
                          + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
                if (type == TYPE_DREAM) {
                    Slog.w(TAG, "Attempted to add Dream window with unknown token "
                          + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
                if (type == TYPE_ACCESSIBILITY_OVERLAY) {
                    Slog.w(TAG, "Attempted to add Accessibility overlay window with unknown token "
                            + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
                token = new WindowToken(this, attrs.token, -1, false);
                addToken = true;
            } else if (type >= FIRST_APPLICATION_WINDOW && type <= LAST_APPLICATION_WINDOW) {
                AppWindowToken atoken = token.appWindowToken;
                if (atoken == null) {
                    Slog.w(TAG, "Attempted to add window with non-application token "
                          + token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_NOT_APP_TOKEN;
                } else if (atoken.removed) {
                    Slog.w(TAG, "Attempted to add window with exiting application token "
                          + token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_APP_EXITING;
                }
                if (type == TYPE_APPLICATION_STARTING && atoken.firstWindowDrawn) {
                    // No need for this guy!
                    if (localLOGV) Slog.v(
                            TAG, "**** NO NEED TO START: " + attrs.getTitle());
                    return WindowManagerGlobal.ADD_STARTING_NOT_NEEDED;
                }
            } else if (type == TYPE_INPUT_METHOD) {
                if (token.windowType != TYPE_INPUT_METHOD) {
                    Slog.w(TAG, "Attempted to add input method window with bad token "
                            + attrs.token + ".  Aborting.");
                      return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
            } else if (type == TYPE_VOICE_INTERACTION) {
                if (token.windowType != TYPE_VOICE_INTERACTION) {
                    Slog.w(TAG, "Attempted to add voice interaction window with bad token "
                            + attrs.token + ".  Aborting.");
                      return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
            } else if (type == TYPE_WALLPAPER) {
                if (token.windowType != TYPE_WALLPAPER) {
                    Slog.w(TAG, "Attempted to add wallpaper window with bad token "
                            + attrs.token + ".  Aborting.");
                      return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
            } else if (type == TYPE_DREAM) {
                if (token.windowType != TYPE_DREAM) {
                    Slog.w(TAG, "Attempted to add Dream window with bad token "
                            + attrs.token + ".  Aborting.");
                      return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
            } else if (type == TYPE_ACCESSIBILITY_OVERLAY) {
                if (token.windowType != TYPE_ACCESSIBILITY_OVERLAY) {
                    Slog.w(TAG, "Attempted to add Accessibility overlay window with bad token "
                            + attrs.token + ".  Aborting.");
                    return WindowManagerGlobal.ADD_BAD_APP_TOKEN;
                }
            } else if (token.appWindowToken != null) {
                Slog.w(TAG, "Non-null appWindowToken for system window of type=" + type);
                // It is not valid to use an app token with other system types; we will
                // instead make a new token for it (as if null had been passed in for the token).
                attrs.token = null;
                token = new WindowToken(this, null, -1, false);
                addToken = true;
            }

mWindowMap

然后就新建一个WindowState对象，加入到mWindowMap中，注意这里的key是client.asBinder

            WindowState win = new WindowState(this, session, client, token,
                    attachedWindow, appOp[0], seq, attrs, viewVisibility, displayContent);
            ......
            win.attach();
            mWindowMap.put(client.asBinder(), win);

这里的client，是ViewRootImpl的mWindow 对象用来和WMS通信的，一个ViewRootImpl一个mWindow对象。

        mWindow = new W(this);

token.windows

再回到addWindow函数，下面是关于新窗口确定插入的位置的相关代码：

            if (type == TYPE_INPUT_METHOD) {
                win.mGivenInsetsPending = true;
                mInputMethodWindow = win;
                addInputMethodWindowToListLocked(win);
                imMayMove = false;
            } else if (type == TYPE_INPUT_METHOD_DIALOG) {
                mInputMethodDialogs.add(win);
                addWindowToListInOrderLocked(win, true);
                moveInputMethodDialogsLocked(findDesiredInputMethodWindowIndexLocked(true));
                imMayMove = false;
            } else {
                addWindowToListInOrderLocked(win, true);
                if (type == TYPE_WALLPAPER) {
                    mLastWallpaperTimeoutTime = 0;
                    displayContent.pendingLayoutChanges |= FINISH_LAYOUT_REDO_WALLPAPER;
                } else if ((attrs.flags&FLAG_SHOW_WALLPAPER) != 0) {
                    displayContent.pendingLayoutChanges |= FINISH_LAYOUT_REDO_WALLPAPER;
                } else if (mWallpaperTarget != null
                        && mWallpaperTarget.mLayer >= win.mBaseLayer) {
                    // If there is currently a wallpaper being shown, and
                    // the base layer of the new window is below the current
                    // layer of the target window, then adjust the wallpaper.
                    // This is to avoid a new window being placed between the
                    // wallpaper and its target.
                    displayContent.pendingLayoutChanges |= FINISH_LAYOUT_REDO_WALLPAPER;
                }
            }

我们主要看下addWindowToListInOrderLocked函数，这个函数分有附属窗口和没有附属窗口，我们先看下有附属窗口的处理。

    private void addWindowToListInOrderLocked(final WindowState win, boolean addToToken) {
        if (DEBUG_FOCUS_LIGHT) Slog.d(TAG, "addWindowToListInOrderLocked: win=" + win +
                " Callers=" + Debug.getCallers(4));
        if (win.mAttachedWindow == null) {
            final WindowToken token = win.mToken;
            int tokenWindowsPos = 0;
            if (token.appWindowToken != null) {
                tokenWindowsPos = addAppWindowToListLocked(win);
            } else {
                addFreeWindowToListLocked(win);
            }
            if (addToToken) {
                if (DEBUG_ADD_REMOVE) Slog.v(TAG, "Adding " + win + " to " + token);
                token.windows.add(tokenWindowsPos, win);
            }
        } else {
            addAttachedWindowToListLocked(win, addToToken);
        }

        if (win.mAppToken != null && addToToken) {
            win.mAppToken.allAppWindows.add(win);
        }
    }

addAttachedWindowToListLocked函数，先调用getTokenWindowsOnDisplay函数，来得到所有这个WindowToken的WindowState，然后根据这个WindowState插入合适位置。并且把要插入的windowState，也放入token.windows。

    private void addAttachedWindowToListLocked(final WindowState win, boolean addToToken) {
        final WindowToken token = win.mToken;
        final DisplayContent displayContent = win.getDisplayContent();
        if (displayContent == null) {
            return;
        }
        final WindowState attached = win.mAttachedWindow;

        WindowList tokenWindowList = getTokenWindowsOnDisplay(token, displayContent);

        // Figure out this window's ordering relative to the window
        // it is attached to.
        final int NA = tokenWindowList.size();
        final int sublayer = win.mSubLayer;
        int largestSublayer = Integer.MIN_VALUE;
        WindowState windowWithLargestSublayer = null;
        int i;
        for (i = 0; i < NA; i++) {
            WindowState w = tokenWindowList.get(i);
            final int wSublayer = w.mSubLayer;
            if (wSublayer >= largestSublayer) {
                largestSublayer = wSublayer;
                windowWithLargestSublayer = w;
            }
            if (sublayer < 0) {
                // For negative sublayers, we go below all windows
                // in the same sublayer.
                if (wSublayer >= sublayer) {
                    if (addToToken) {
                        if (DEBUG_ADD_REMOVE) Slog.v(TAG, "Adding " + win + " to " + token);
                        token.windows.add(i, win);//放入WindowToken的windows
                    }
                    placeWindowBefore(wSublayer >= 0 ? attached : w, win);//插入合适位置
                    break;
                }
            } else {
                // For positive sublayers, we go above all windows
                // in the same sublayer.
                if (wSublayer > sublayer) {
                    if (addToToken) {
                        if (DEBUG_ADD_REMOVE) Slog.v(TAG, "Adding " + win + " to " + token);
                        token.windows.add(i, win);
                    }
                    placeWindowBefore(w, win);
                    break;
                }
            }
        }
        if (i >= NA) {
            if (addToToken) {
                if (DEBUG_ADD_REMOVE) Slog.v(TAG, "Adding " + win + " to " + token);
                token.windows.add(win);
            }
            if (sublayer < 0) {
                placeWindowBefore(attached, win);
            } else {
                placeWindowAfter(largestSublayer >= 0
                                 ? windowWithLargestSublayer
                                 : attached,
                                 win);
            }
        }
    }

我们先看下getTokenWindowsOnDisplay函数，就是遍历WindowToken的windows，是得同一个DisplayContent对象。

    WindowList getTokenWindowsOnDisplay(WindowToken token, DisplayContent displayContent) {
        final WindowList windowList = new WindowList();
        final int count = token.windows.size();
        for (int i = 0; i < count; i++) {
            final WindowState win = token.windows.get(i);
            if (win.getDisplayContent() == displayContent) {
                windowList.add(win);
            }
        }
        return windowList;
    }

DisplayContent的mWindows

再来看placeWindowBefore函数，插入到windows的pos位置

    private void placeWindowBefore(WindowState pos, WindowState window) {
        final WindowList windows = pos.getWindowList();
        int i = windows.indexOf(pos);
        if (DEBUG_FOCUS || DEBUG_WINDOW_MOVEMENT || DEBUG_ADD_REMOVE) Slog.v(
            TAG, "Adding window " + window + " at "
            + i + " of " + windows.size() + " (before " + pos + ")");
        if (i < 0) {
            Slog.w(TAG, "placeWindowBefore: Unable to find " + pos + " in " + windows);
            i = 0;
        }
        windows.add(i, window);
        mWindowsChanged = true;
    }

getWindowList就是返回DisplayContent 得到mWindows，所以在placeWindowBefore插入window，最终也都是插入DisplayContent的mWindows

    WindowList getWindowList() {
        final DisplayContent displayContent = getDisplayContent();
        return displayContent == null ? null : displayContent.getWindowList();
    }

继续看addWindowToListInOrderLocked函数，对没有附属窗口的调用addAppWindowToListLocked，就是调用WindowState的getWindowList来获取displayContent.getWindowList，然后调用placeWindowBefore插入合适的位置。

    private int addAppWindowToListLocked(final WindowState win) {
        final IWindow client = win.mClient;
        final WindowToken token = win.mToken;
        final DisplayContent displayContent = win.getDisplayContent();
        if (displayContent == null) {
            // It doesn't matter this display is going away.
            return 0;
        }

        final WindowList windows = win.getWindowList();
        final int N = windows.size();
        WindowList tokenWindowList = getTokenWindowsOnDisplay(token, displayContent);
        int tokenWindowsPos = 0;
        int windowListPos = tokenWindowList.size();
        if (!tokenWindowList.isEmpty()) {
            // If this application has existing windows, we
            // simply place the new window on top of them... but
            // keep the starting window on top.
            if (win.mAttrs.type == TYPE_BASE_APPLICATION) {
                // Base windows go behind everything else.
                WindowState lowestWindow = tokenWindowList.get(0);
                placeWindowBefore(lowestWindow, win);
                ......
            }
        }
    }

Task TaskStack

我们再来看看WMS的addAppToken函数，这个函数中新建了APPWindowToken之后，会看mTaskIdToTask是否有这个taskId，没有会调用createTaskLocked根据AMS传进来的taskId和stackId创建Task和TaskStack。

            AppWindowToken atoken = findAppWindowToken(token.asBinder());
            if (atoken != null) {
                Slog.w(TAG, "Attempted to add existing app token: " + token);
                return;
            }
            atoken = new AppWindowToken(this, token, voiceInteraction);
            ......

            Task task = mTaskIdToTask.get(taskId);
            if (task == null) {
                task = createTaskLocked(taskId, stackId, userId, atoken);
            }
            task.addAppToken(addPos, atoken);

            mTokenMap.put(token.asBinder(), atoken);

createTaskLocked函数如下，TaskStack会在ActivityStackSupervisor中调用WMS的attachStack函数创建，这里然后创建Task，再把task放入mTaskIdToTask中。再把task加入到TaskStack中。

    private Task createTaskLocked(int taskId, int stackId, int userId, AppWindowToken atoken) {
        if (DEBUG_STACK) Slog.i(TAG, "createTaskLocked: taskId=" + taskId + " stackId=" + stackId
                + " atoken=" + atoken);
        final TaskStack stack = mStackIdToStack.get(stackId);
        if (stack == null) {
            throw new IllegalArgumentException("addAppToken: invalid stackId=" + stackId);
        }
        EventLog.writeEvent(EventLogTags.WM_TASK_CREATED, taskId, stackId);
        Task task = new Task(taskId, stack, userId, this);
        mTaskIdToTask.put(taskId, task);
        stack.addTask(task, !atoken.mLaunchTaskBehind /* toTop */, atoken.showForAllUsers);
        return task;
    }

WMS的attachStack函数如下，当mStackIdToStack没有这个stackId，这个时候新建TaskStack，然后加入到mStackIdToStack。

    public void attachStack(int stackId, int displayId) {
        final long origId = Binder.clearCallingIdentity();
        try {
            synchronized (mWindowMap) {
                final DisplayContent displayContent = mDisplayContents.get(displayId);
                if (displayContent != null) {
                    TaskStack stack = mStackIdToStack.get(stackId);
                    if (stack == null) {
                        if (DEBUG_STACK) Slog.d(TAG, "attachStack: stackId=" + stackId);
                        stack = new TaskStack(this, stackId);//新建TaskStack
                        mStackIdToStack.put(stackId, stack);//加入到mStackIdToStack
                    }
                    stack.attachDisplayContent(displayContent);
                    displayContent.attachStack(stack);
                    moveStackWindowsLocked(displayContent);
                    final WindowList windows = displayContent.getWindowList();
                    for (int winNdx = windows.size() - 1; winNdx >= 0; --winNdx) {
                        windows.get(winNdx).reportResized();
                    }
                }
            }

AppWindowToken 的mTask

我们再回到WMS的addAppToken函数，创建完task，之后调用了Task的addAppToken函数

            Task task = mTaskIdToTask.get(taskId);
            if (task == null) {
                task = createTaskLocked(taskId, stackId, userId, atoken);
            }
            task.addAppToken(addPos, atoken);

Task的addAppToken把AppWindowToken 放入到Task的mAppTokens中，并且赋值AppWindowToken 的mTask

    void addAppToken(int addPos, AppWindowToken wtoken) {
        final int lastPos = mAppTokens.size();
        if (addPos >= lastPos) {
            addPos = lastPos;
        } else {
            for (int pos = 0; pos < lastPos && pos < addPos; ++pos) {
                if (mAppTokens.get(pos).removed) {
                    // addPos assumes removed tokens are actually gone.
                    ++addPos;
                }
            }
        }
        mAppTokens.add(addPos, wtoken);
        wtoken.mTask = this;
        mDeferRemoval = false;
    }