Android List view refresh
I have one ListView which is showing me some data through an array (which is in another class and I'm accessi开发者_运维技巧ng it through it's object).
Whenever I delete an element from the ListView through context menu, the list is not refreshing but the element is deleted from the array. How can I refresh the list to show this?
Code:
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
if (v.getId()==R.id.mainListView) {
AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo)menuInfo;
post=info.position;
menu.setHeaderTitle(stocks[info.position]);
String[] menuItems = stt;
for (int i = 0; i<menuItems.length; i++) {
menu.add(Menu.NONE, i, i, menuItems[i]);
}
}
}
@Override
public boolean onContextItemSelected(MenuItem item) {
AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo)item.getMenuInfo();
int menuItemIndex = item.getItemId();
String[] menuItems = stt;
String menuItemName = menuItems[menuItemIndex];
listItemName = stocks[info.position];
stockname.remove(post-1);
return true;
}
You have to notify your ListView adapter that the data has changed.
listViewAdapater.notifyDataSetChanged();
If that for some reason doesn't work and there are some wierd situations where it seems like it wasn't notifying, you can just reassign your adapter via the constructor with the updated array.
I have no notifyDataSetChanged()
method (Android 2.3).
The following worked for me:
getListView().invalidate();
In my case I have changed the whole adapter and it still didn't refresh, so for me the method described above is the only working solution.
Try getListView().refreshDrawableState
private static ArrayList<Radio> m_streamsList;
final ListView listView = (ListView) rootView.findViewById(R.id.stream_listRS);
//my class where i insert data into my array
m_myDBHelp = new DBHelper();
m_streamsList = m_myDBHelp.selectStreamsList();
// my list adapter - this is a class created by me
RadioAdapter adapt = new RadioAdapter(context, m_streamsList);
listView.setAdapter(adapt);
////////////------------- so . when i inserted a row in db, i need to refresh the list
m_myDBHelp.insertStreamIntoDB(String name, String url);
/// in my case method invalidate works fine
listView.invalidate();
m_streamsList = null;
m_streamsList = m_myDBHelp.selectStreamsList();
//you need to set adapter again
RadioAdapter adapt2 = new RadioAdapter(context, m_streamsList);
listView.setAdapter(adapt2);
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.example.npopa.musicplayern.R;
import com.example.npopa.musicplayern.Radio;
import java.util.ArrayList;
public class RadioAdapter extends BaseAdapter{
private ArrayList<Radio> m_streams;
private LayoutInflater m_stramInf;
public RadioAdapter(Context c, ArrayList<Radio> theStreams){
m_streams = theStreams;
m_stramInf = LayoutInflater.from(c);
}
@Override
public int getCount() {
return m_streams.size();
}
@Override
public Object getItem(int arg0) {
return null;
}
@Override
public long getItemId(int arg0) {
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
//map to radio_s layout
LinearLayout streamLay = (LinearLayout) m_stramInf.inflate(R.layout.all_songs_t, parent, false);
TextView name = (TextView) streamLay.findViewById(R.id.song_title);
TextView url = (TextView) streamLay.findViewById(R.id.song_artist);
ImageView imgALb = (ImageView) streamLay.findViewById(R.id.albumicon);
//get all_songs_t using position
Radio currStream = m_streams.get(position);
name.setText(currStream.getName());
url.setText(currStream.getUrl());
imgALb.setImageResource(R.drawable.radio_stream);
//set position as tag
streamLay.setTag(position);
return streamLay;
}
}
public class Radio {
private int id;
private String name;
private String url;
public Radio(int id, String name, String url) {
this.id = id;
this.name = name;
this.url = url;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
}
List refreshing for me: listView.invalidateViews();
It'll do:
mDataChanged = true;
rememberSyncState();
requestLayout();
invalidate();
The case as to manage some list item removal or removal all element at once.
Tested in API 24.
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