I have an activity that contains a FragmentStatePagerAdapter within this FragmentStatePagerAdapter there are three fragments. Or well, they get initiated when the proper getItem() is called.
The activity does a data intensive task, and when it is finished sends a broadcast. I have registered a broadcast receiver in every fragment within the FragmentStatePagerAdapter.
Now this all works fine except for one thing:
- When we scroll to the fragment at position 2 (both position 1 and 2 work properly) the fragment at position 0 is cleared and doesn't return.
Here are some of my code samples:
The FragmentStatePagerAdapter
public class MessagePagerAdapter extends FragmentStatePagerAdapter {
public MessagePagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int arg0) {
if(arg0 == 0) {
Fragment fragment = new RecentConversationFragment();
return fragment;
} else if(arg0 == 1) {
Fragment fragment = new PrivateConversationFragment();
return fragment;
} else {
Fragment fragment = new ClanConversationFragment();
return fragment;
}
}
@Override
public int getCount() {
return 3;
}
@Override
public CharSequence getPageTitle(int position) {
if(position == 0) {
return "Recent";
} else if(position == 1) {
return "Private";
} else {
return "Clan";
}
}
The relevant parts of the activity
When the data is received I broadcast an intent
Intent recentIntent = new Intent("MESSAGE_LOADER_RECENT");
MessageActivity.this.sendBroadcast(recentIntent);
This broadcast is received in my fragment like this:
private void createReceiver() {
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("MESSAGE_LOADER_RECENT");
receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
fetchMessages();
}
};
getActivity().getApplicationContext().registerReceiver(receiver,
intentFilter);
}
private void fetchMessages() {
this.conversations = mActivity.getRecentPrivateConversations();
messageListView.setAdapter(new ConversationListAdapter(mActivity,
R.layout.conversation_row, conversations));
messageListView.setDivider(null);
messageListView.setDividerHeight(0);
mActivity.recentConversationBroadcastReceived = true;
messageListView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
mActivity.navigateToConversation(conversations.get(position));
}
});
}
Note that I set mActivity.recentConversationBroadcastReceived = true, I do this because I keep sending broadcasts like this:
In the viewPager.setOnPageChangeListener,
@Override
public void onPageSelected(int arg0) {
//here we check whether a broadcast is already sent to the
//specific fragment, if not we need to send one
if (arg0 == 0 || arg0 == 1) {
// recent or private
if (MessageActivity.this.loadedConversations != null) {
// check if the fragment already received a broadcast
if (arg0 == 0 && !recentConversationBroadcastReceived) {
Intent intent = new Intent("MESSAGE_LOADER_RECENT");
MessageActivity.this.sendBroadcast(intent);
} else if (arg0 == 1
&& !privateConversationBroadcastReceived) {
Intent intent = new Intent("MESSAGE_LOADER_PRIVATE");
MessageActivity.this.sendBroadcast(intent);
}
}
} else {
// clan
if (!clanConversationBroadcastReceived
&& MessageActivity.this.loadedClanConversations != null) {
Intent intent = new Intent("MESSAGE_LOADER_CLAN");
MessageActivity.this.sendBroadcast(intent);
}
}
}
I do this because when I send a broadcast it isn't guaranteed that the current active fragment is the fragment that actually uses the data, and the fragment might not be initiated. So I send a broadcast on every page change until it is received.
I hope someone can help me with this issue.
