[英]update List View onResume (can't get view)
I need to update my List View in onResume function, them problem is that my view is null there: 我需要在onResume函数中更新列表视图,它们的问题是那里的视图为null:
mList = (ListView) v.findViewById(R.id.list); //v is null
what should I do? 我该怎么办? how can I get my list view to update it?
如何获取列表视图进行更新?
Here is part of onCreate function: 这是onCreate函数的一部分:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
View v = findViewById(R.id.large_screen_layout);
mList = (ListView) v.findViewById(R.id.list);
}
Here is the on resume function: 这是恢复时的功能:
@Override
protected void onResume()
{
super.onResume();
mMyBroadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent)
{
// Here you can refresh your listview or other UI
String textmessage = intent.getStringExtra("Message");
Toast.makeText(getApplicationContext(), textmessage, Toast.LENGTH_LONG).show();
item = new RowItem(R.drawable.alert_icon, "text1", "text2");
rowItems.add(item);
adapter = new CustomListViewAdapter(getApplicationContext(),R.id.list,rowItems);
adapter.notifyDataSetChanged();
//now either, i need to use view (v) or mList(List View):
mList = (ListView) v.findViewById(R.id.list); //v and mList are NULL here
mList.setAdapter(adapter);
}
};
try {
LocalBroadcastManager.getInstance(this).registerReceiver(mMyBroadcastReceiver,new IntentFilter("your_action"));
} catch (Exception e)
{
// TODO: handle exception
e.printStackTrace();
}
}
any idea how can I update it? 知道如何更新吗?
Thank you! 谢谢!
Eran. 伊朗
@Override
protected void onResume()
{
super.onResume();
mMyBroadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent)
{
// Here you can refresh your listview or other UI
String textmessage = intent.getStringExtra("Message");
Toast.makeText(getApplicationContext(), textmessage, Toast.LENGTH_LONG).show();
item = new RowItem(R.drawable.alert_icon, "text1", "text2");
rowItems.add(item);
adapter = new CustomListViewAdapter(getApplicationContext(),R.id.list,rowItems);
adapter.notifyDataSetChanged();
//now either, i need to use view (v) or mList(List View):
// need to find V
View v = findViewById(R.id.large_screen_layout);
mList = (ListView) v.findViewById(R.id.list); //v and mList are NULL here
mList.setAdapter(adapter);
}
};
try {
LocalBroadcastManager.getInstance(this).registerReceiver(mMyBroadcastReceiver,new IntentFilter("your_action"));
} catch (Exception e)
{
// TODO: handle exception
e.printStackTrace();
}
}
Also be sure to deregister your broadcast receiver in onPause or it may receive notifications in unexpected ways.. 另外,请务必在onPause上注销广播接收器的注册,否则它可能会以意外方式接收通知。
Change your OnCreate function if you use Activity or FragmentActivity : 如果使用Activity或FragmentActivity,请更改OnCreate函数:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.large_screen_layout);
mList = (ListView)findViewById(R.id.list);
}
Or if u want to use Fragment 或者如果您想使用片段
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
view = inflater.inflate(R.layout.large_screen_layout, null);
mList = (ListView)view.findViewById(R.id.list);
return view;
}
Try this: 尝试这个:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
View v = findViewById(R.id.large_screen_layout);
mList = (ListView) v.findViewById(R.id.list);
adapter = new CustomListViewAdapter(getApplicationContext(),
R.id.list,rowItems);
mList.setAdapter(adapter);}
@Override
protected void onResume() {
super.onResume();
mMyBroadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String textmessage = intent.getStringExtra("Message");
Toast.makeText(getApplicationContext(), textmessage, Toast.LENGTH_LONG).show();
item = new RowItem(R.drawable.alert_icon, "text1", "text2");
rowItems.add(item);
adapter.notifyDataSetChanged();
}
};
try {
LocalBroadcastManager.getInstance(this).registerReceiver(mMyBroadcastReceiver, new IntentFilter("your_action"));
} catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
}
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.