Send a DEBUG log message @param tag @param msg

Send an INFO log message @param tag @param msg

@return true if this adapter doesn't contain any data. This is used to determine whether the empty view should be displayed. A typical implementatio

Call this when data is loaded. The UI will perform complete at once or after a delay, depends on the time elapsed is greater then {@link #mLoadingMinT

@param index Index into the color array of the color to display in the progress spinner.

@return The amount the progress spinner is currently rotated, between [0..1].

@param contentView @param loadMoreView @param onClickLoadMoreListener @return 是否有 init ILoadMoreView

Send a VERBOSE log message. @param tag @param msg

初始化 @param footViewHolder @param onClickLoadMoreListener 加载更多的点击事件，需要点击调用加载更多的按钮都可以设置这个监听

Do real refresh work. If there is a hook, execute the hook first. @param ignoreHook

perform UI after refresh

prepare for loading @param frame

@param show Set to true to show the arrow head on the progress spinner.

If the start / end trim are offset to begin with, store them so that animation starts from that offset.

Scroll back to to if is not under touch

Check can do refresh or not. For example the content is empty or the first child is in view. <p/> {@link PtrDefaultHandler#checkContentCanBePulledDown

Send an ERROR log message @param tag @param msg

Proceed to the next available ring color. This will automatically wrap back to the beginning of colors.