Android ListView 局部刷新

private Handler mHandler = new Handler() {
public void handleMessage(android.os.Message msg) {
int what = msg.what;
switch (what) {
case CMD_UPDATE_TASK:
int index = msg.arg1;
DownloadTask task = mListItem.get(index);
int firstVisible = mListView.getFirstVisiblePosition();
int lastVisible = mListView.getLastVisiblePosition();
if (index >= firstVisible && index <= lastVisible) {
ViewHolder holder = (ViewHolder) (mListView
.getChildAt(index - firstVisible).getTag());
updateListViewItem(holder, task);
}
break;

default:
break;
}
// 避免全部刷新引起按钮响应很慢
// mDownloadListAdapter.notifyDataSetChanged();
};
};

private void updateListViewItem(ViewHolder holder, DownloadTask task) {
// Log.d(TAG, "updateListViewItem "+task);
holder.title.setText(task.name);
holder.progress.setProgress(task.percent);
switch (task.status) {
case NOT_STARTED:
holder.status.setText("开始");
break;
case RUNNING:
holder.status.setText("下载中");
break;
case PAUSING:
holder.status.setText("暂停");
break;
case WAITING:
holder.status.setText("等待");
break;
case FINISHED:
holder.status.setText("完成");
break;
default:
break;
}
}