电子技术论坛_中国专业的电子工程师学习交流社区-中电网技术论坛

标题: Picasso使用简介及分析（9） [打印本页]

作者: look_w 时间: 2019-2-18 19:57 标题: Picasso使用简介及分析（9）

10. 当从硬盘或者服务器获取Bitmap之后，就可以通过Action来执行各种自定义的callback了

//dispatcher.dispatchComplete()用来处理bitmap成功获取后的逻辑，
//经过一系列的转发，最终逻辑是在Picasso类里的complete方法中执行的。
void complete(BitmapHunter hunter) {
   Action single = hunter.getAction();
   List<Action> joined = hunter.getActions();
   boolean hasMultiple = joined != null && !joined.isEmpty();
   boolean shouldDeliver = single != null || hasMultiple;
   if (!shouldDeliver) {
      return;
   }
   Uri uri = hunter.getData().uri;
   Exception exception = hunter.getException();
   Bitmap result = hunter.getResult();
   LoadedFrom from = hunter.getLoadedFrom();
   if (single != null) {
      deliverAction(result, from, single);
   }
   if (hasMultiple) {
      //noinspection ForLoopReplaceableByForEach
      for (int i = 0, n = joined.size(); i < n; i++) {
      Action join = joined.get(i);
      deliverAction(result, from, join);
      }
   }
   if (listener != null && exception != null) {
      listener.onImageLoadFailed(this, uri, exception);
      }
   }


private void deliverAction(Bitmap result, LoadedFrom from, Action action) {
   if (action.isCancelled()) {
      return;
   }
   if (!action.willReplay()) {
      targetToAction.remove(action.getTarget());
   }
   if (result != null) {
      if (from == null) {
         throw new AssertionError("LoadedFrom cannot be null.");
      }
      //这里的action就是前面提到的ImageViewAction，其他还有RemoteViewsAction，TargetAction等
      action.complete(result, from);
      ...
   } else {
      action.error();
      ...
   }
}

欢迎光临电子技术论坛_中国专业的电子工程师学习交流社区-中电网技术论坛 (http://bbs.eccn.com/)