我有一个数据集,可能会在刷新时发生变化。确定现有数据集中的哪些条目已被更改是非常不可预测的。我通读了recyclerview适配器描述和我遇到的主要问题。
更有效地确定哪些数据视图已更改,然后对受影响的范围使用notifyItemRangeChanged,还是应该在每次更改数据视图后逐个更改它们然后再更改notifyItemChanged?
稍微复杂一点,因为根据改变的内容,每个视图的顺序可能已经改变,然后它是为受影响的范围调用notifyItemRangeInserted,notifyItemRangeRemoved或逐个调用notifyItemMoved的参数?
这种方式或其他方式更有效吗?
由于
答案 0 :(得分:5)
这是源代码v7-22.1.1
/**
* Notify any registered observers that the item at <code>position</code> has changed.
*
* <p>This is an item change event, not a structural change event. It indicates that any
* reflection of the data at <code>position</code> is out of date and should be updated.
* The item at <code>position</code> retains the same identity.</p>
*
* @param position Position of the item that has changed
*
* @see #notifyItemRangeChanged(int, int)
*/
public final void notifyItemChanged(int position) {
mObservable.notifyItemRangeChanged(position, 1);
}
/**
* Notify any registered observers that the <code>itemCount</code> items starting at
* position <code>positionStart</code> have changed.
*
* <p>This is an item change event, not a structural change event. It indicates that
* any reflection of the data in the given position range is out of date and should
* be updated. The items in the given range retain the same identity.</p>
*
* @param positionStart Position of the first item that has changed
* @param itemCount Number of items that have changed
*
* @see #notifyItemChanged(int)
*/
public final void notifyItemRangeChanged(int positionStart, int itemCount) {
mObservable.notifyItemRangeChanged(positionStart, itemCount);
}
因此,notifyItemChanged(int)
notifyItemRangeChanged(int, int)
答案 1 :(得分:2)
RecyclerView还没有&#39;尽可能合并这些变更事件虽然这是我们正在考虑的事情(低优先级)。
除非您要发送数百个事件,否则它应该没问题,但如果您可以发送Range
事件,那么对RecyclerView来说当然更好。