使用recyclerView时一般用notifyItemChanged(int position)刷新列表某一项，onBindViewHolder(@NonNull VH holder, int position)会被调用，在这里处理ui变化。
当频繁调用（如修改进度百分比）时，该item的onBindViewHolder会被频繁调用，如果还有耗时操作或图片加载，会导致资源浪费或图片闪动。而我们需要的只是修改该item的部分UI，其他操作都是不必要的。
找了下recyclerView的api，确实有部分刷新item的方法：

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/**
 * Notify any registered observers that the item at <code>position</code> has changed with
 * an optional payload object.
 *
 * <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 is out of date and should be updated.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>
 *
 * <p>
 * Client can optionally pass a payload for partial change. These payloads will be merged
 * and may be passed to adapter's {@link #onBindViewHolder(ViewHolder, int, List)} if the
 * item is already represented by a ViewHolder and it will be rebound to the same
 * ViewHolder. A notifyItemRangeChanged() with null payload will clear all existing
 * payloads on that item and prevent future payload until
 * {@link #onBindViewHolder(ViewHolder, int, List)} is called. Adapter should not assume
 * that the payload will always be passed to onBindViewHolder(), e.g. when the view is not
 * attached, the payload will be simply dropped.
 *
 * @param position Position of the item that has changed
 * @param payload Optional parameter, use null to identify a "full" update
 *
 * @see #notifyItemRangeChanged(int, int)
 */
public final void notifyItemChanged(int position, @Nullable Object payload) {
    mObservable.notifyItemRangeChanged(position, 1, payload);
}

根据以上注释，实现onBindViewHolder(@NonNull VH holder, int position, @NonNull List<Object> payloads)

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public void onBindViewHolder(@NonNull VH holder, int position, @NonNull List<Object> payloads){
    if (preloads.isEmpty()){
        onBindViewHolder(holder, position);
    } else {
        // 实现局部刷新逻辑
        ...
    }
}

按以上方法实现刷新item局部UI后，就会发现图片不再闪动了，大功告成！