我有一个带有像这样的项目装饰的recyclerView:
public class VerticalItemDecoration extends RecyclerView.ItemDecoration{
private int space;
public VerticalItemDecoration(int space){
this.space = space;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state){
outRect.top = space;
Log.e("Decor", "Parent: " + parent + " Childs: " + parent.getChildCount());
if (parent.getChildLayoutPosition(view) == 0){
outRect.top = 0;
}
}
}
每10秒钟,我在此回收站视图中迭代数据并调用iterator.remove()
。在那之后,我通知适配器项目已被删除。但是,在删除项目后,将为该回收站视图调用两次getItemOffsets()
。它第一次显示1个子视图,这是正确的,因为我删除了一个。但在此之后它再次被调用并报告2个子视图。只有在删除项目时才会发生这种情况。造成这种情况的原因是什么?
我正在这样迭代:
for (Iterator<Client> iterator = AdapterClients.listClients.iterator(); iterator.hasNext();){
Client client1 = iterator.next();
if (client.getMacAddress().equals(client1.getMacAddress())){
//This client is already on the adapter
clientExists = true;
//Make sure the client is still reachable
if (ApManager.isClientReachable(client1, 3000)){
//Client is still reachable
//Update the client's information
if (client1.getHostName().equals("Unknown Host Name")){
client1.setHostName(ApManager.getHostName(client1));
notifyAdapter("itemChanged", AdapterClients.listClients.indexOf(client1));
}
}else{
//Client is no longer reachable, remove it from the adapter
int index = AdapterClients.listClients.indexOf(client1);
iterator.remove();
Log.e("Arp", "index: " + index + " objIndex: " + AdapterClients.listClients.indexOf(client1));
notifyAdapter("itemRemoved", index);
DataLogger.log("Client " + client1.getIpAddress() + " disconnected from \"" + ApManager.getActiveHotspot().getSsid() + "\"");
}
}
}
notifyAdapter()
方法如下所示:
private static void notifyAdapter(final String action, final int index){
new Handler(Looper.getMainLooper()).post(new Runnable(){
@Override
public void run(){
switch (action){
case "itemInserted":
Log.e("Arp", "itemInserted");
FragmentClients.adapterClients.notifyItemInserted(index);
break;
case "itemRemoved":
Log.e("Arp", "itemRemoved");
FragmentClients.adapterClients.notifyItemRemoved(index);
Log.e("Arp", "after itemRemoved");
break;
//Other cases...
}
FragmentClients.updateText();
//FragmentClients.adapterClients.notifyItemChanged(0);
FragmentHotspots.adapterHotspots.notifyItemChanged(AdapterHotspots.listHotspots.indexOf(ApManager.getActiveHotspot()));
}
});
}
这是logcat的输出:
05-23 18:58:57.143 4726-5658/com.example E/Arp: index: 0 objIndex: -1
05-23 18:58:57.154 4726-4726/com.example E/Arp: itemRemoved
05-23 18:58:57.154 4726-4726/com.example E/Arp: after itemRemoved
05-23 18:58:57.171 4726-4726/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{b0a533b VFED.... .F....I. 0,0-1080,1509 #7f0e009b app:id/recyclerViewClients} Childs: 1
05-23 18:58:57.174 4726-4726/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{b0a533b VFED.... .F....I. 0,0-1080,1509 #7f0e009b app:id/recyclerViewClients} Childs: 2
05-23 18:58:57.187 4726-4726/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{3d927634 VFED.... ......I. 0,0-1080,1509 #7f0e009d app:id/recyclerViewHotspots} Childs: 1
注意:使用notifyDataSetChanged()
代替notifyItemRemoved()
有效,但动画未显示。
答案 0 :(得分:0)
我已通过将getItemOffsets()
方法更改为此
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state){
outRect.top = space;
Log.e("Decor", "Parent: " + parent + " Childs: " + parent.getChildCount() + " pos: " + parent.getChildLayoutPosition(view));
if (parent.getChildCount() == 1){
outRect.top = 0;
}
}
在调用notifyItemRemoved()
时,似乎视图以错误的顺序更新,因为在初始化期间,日志是:
05-23 20:51:56.889 14129-14129/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{323b3d54 VFED.... ......ID 0,0-1080,1845 #7f0e009d app:id/recyclerViewHotspots} Childs: 1 pos: 0
05-23 20:51:56.895 14129-14129/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{323b3d54 VFED.... ......ID 0,0-1080,1845 #7f0e009d app:id/recyclerViewHotspots} Childs: 2 pos: 1
05-23 20:51:56.899 14129-14129/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{323b3d54 VFED.... ......ID 0,0-1080,1845 #7f0e009d app:id/recyclerViewHotspots} Childs: 3 pos: 2
删除第一项后,日志为:
05-23 20:52:15.498 14129-14129/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{323b3d54 VFED.... .F....I. 0,0-1080,1509 #7f0e009d app:id/recyclerViewHotspots} Childs: 1 pos: 1
05-23 20:52:15.499 14129-14129/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{323b3d54 VFED.... .F....ID 0,0-1080,1509 #7f0e009d app:id/recyclerViewHotspots} Childs: 2 pos: 2
05-23 20:52:15.499 14129-14129/com.example E/Decor: Parent: android.support.v7.widget.RecyclerView{323b3d54 VFED.... .F....ID 0,0-1080,1509 #7f0e009d app:id/recyclerViewHotspots} Childs: 3 pos: 0
在调用notifyItemRemoved
之后很清楚,它没有从回收站视图中正确删除视图,而是最后更新它而不是第一次。