AbstractListView源码分析8

/**
     * Maximum distance to record overscroll 记录overscroll的最大的距离
     */
    int mOverscrollMax;


    /**
     * Content height divided by this is the overscroll limit.内容的高度除以这个数值，为overscroll的limit
     */

    static final int OVERSCROLL_LIMIT_DIVISOR = 3;

/**
     * How many positions in either direction we will search to try to
     * find a checked item with a stable ID that moved position across
     * a data set change. If the item isn't found it will be unselected.
     */
    private static final int CHECK_POSITION_SEARCH_DISTANCE = 20;在一个方向将要搜索的位置数目，来寻找一个checked的条目（带有stable ID）整个数据集的改变。如果这个item没有被发现，它将是unselected。

 /**
     * Used to request a layout when we changed touch mode被用来请求一个布局当我们改变了touchmode
     */
    private static final int TOUCH_MODE_UNKNOWN = -1;
    private static final int TOUCH_MODE_ON = 0;
    private static final int TOUCH_MODE_OFF = 1;

 private int mLastTouchMode = TOUCH_MODE_UNKNOWN;

    private static final boolean PROFILE_SCROLLING = false;
    private boolean mScrollProfilingStarted = false;

/**
     * The StrictMode "critical time span" objects to catch animation
     * stutters.  Non-null when a time-sensitive animation is
     * in-flight.  Must call finish() on them when done animating.
     * These are no-ops on user builds.
     */
    private StrictMode.Span mScrollStrictSpan = null;
    private StrictMode.Span mFlingStrictSpan = null;

/**
     * The last CheckForLongPress runnable we posted, if any
     */
    private CheckForLongPress mPendingCheckForLongPress;


    /**
     * The last CheckForTap runnable we posted, if any
     */
    private CheckForTap mPendingCheckForTap;


    /**
     * The last CheckForKeyLongPress runnable we posted, if any
     */
    private CheckForKeyLongPress mPendingCheckForKeyLongPress;