本文是实际开发遇到的问题,结合情景,给出解决方案,很有启示作用。
1、比如列表有收藏按钮,当前页面收藏
private List> mList = new ArrayList<>();
...
mList.get(position).put("favorites", "1");
notifyDataSetChanged();2、比如列表有收藏按钮,下个页面也有收藏功能
这种情况下,下个页面收藏成功后,按照常理最好返回列表页刷新以下收藏按钮的状态(话说新浪微博没有这样做)。
DataAdapter
Intent intent = new Intent(activity, NextActivity.class);
intent.putExtra("position", position);
startActivityForResult(intent,AppConfig.REQUEST_CODE_DIALOGUE);NextActivity.class
Intent intent;
intent = new Intent();
Bundle bundle = new Bundle();
bundle.putInt("position", position);
bundle.putString("isCollection", "1";intent.putExtras(bundle);
setResult(RESULT_OK, intent);
finish();onActivityResult 回到上页面的onActivityResult方法
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == AppConfig.REQUEST_CODE_DIALOGUE
&& resultCode == RESULT_OK) {
int position = data.getExtras().getInt("position");
String isCollection = data.getExtras().getString("isCollection ");
Object object = dataAdapter.getItem(position);
if (object instanceof DoctorList) {
DoctorList doctorList = (DoctorList) object;
doctorList.setIsCollection(isCollection);
dataAdapter.notifyDataSetChanged();
}
} super.onActivityResult(requestCode, resultCode, data);
}DoctorList
class DialogueBean {
private String result;
private ArrayList doctorList;
public class DoctorList implements Serializable {
private String isCollection;
}
}3、以上只是未重新请求接口下刷新View,未真正局部刷新
以上应该是大部分人会使用的一种解决思路,但是很抱歉,使用notifyDataSetChanged方法,未做到局部刷新。
ListView局部刷新
private List> mData; private ListView mListView; @Override
protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mData = getData();
MyAdapter adapter = new MyAdapter(this);
mListView = (ListView) findViewById(R.id.listView);
mListView.setAdapter(adapter);
} private List> getData() {
List> list = new ArrayList<>();
Map map; for (int i = 0; i < 50; i++) {
map = new HashMap<>();
map.put("title", "G" + i);
list.add(map);
} return list;
} public class MyAdapter extends BaseAdapter { private LayoutInflater mInflater; public MyAdapter(Context context) { this.mInflater = LayoutInflater.from(context);
} @Override
public int getCount() { return mData.size();
} @Override
public Object getItem(int arg0) { return mData.get(arg0);
} @Override
public long getItemId(int arg0) { return arg0;
} @Override
public View getView(final int position, View convertView, ViewGroup parent) {
Log.d("wxl", "getView=" + position);
ViewHolder holder = null; if (convertView == null) {
holder = new ViewHolder();
convertView = mInflater.inflate(R.layout.listview_item, null);
holder.textview = (TextView) convertView.findViewById(R.id.textview);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.textview.setText((String) mData.get(position).get("title"));
convertView.setOnClickListener(new View.OnClickListener() { @Override
public void onClick(View v) {
updateItemView(position);
}
}); return convertView;
} public class ViewHolder { public TextView textview;
}
} public void updateItemView(int position) {
int visiblePosition = mListView.getFirstVisiblePosition();
int index = position - visiblePosition;
if (index >= 0) {
View view = mListView.getChildAt(index);
MyAdapter.ViewHolder holder = (MyAdapter.ViewHolder) view.getTag();
holder.textview.setText("测试数据");
mData.get(index).put("title", "测试数据");
}
}
}listview_item.xml
RecyclerView局部刷新
RecyclerView已经替代了ListView,局部刷新很有必要知道
mList.get(position).put("favorites", "0");ViewHolder viewHolder = (ViewHolder) mRecyclerView.findViewHolderForAdapterPosition(position); viewHolder.mCheck.setBackgroundResource(R.mipmap.collect_normal);要想了解更多,可以点击底部「阅读原文」跳转至我的博客。
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