Does backendless support querying data from another Backendless App Table? If yes how.
If I have Backendless App called Music with Table songs and I have another App called Movie. I want to query the song table from the Movie app.
You gonna need to call Backendless.initApp(context, {another_app_id}, {another_app_secret_key}, v1) before each call to a different application. This way you'll be able to talk to any number of apps.
#Save
useres useres = new useres();
useres.setName("Amin");
useres.setId("DOREH");
useres.setScore("20");
useres.setData("2016.12.24");
Backendless.Persistence.save(useres, new AsyncCallback<com.example.amin.bback.useres>() {
#Override
public void handleResponse(useres response)
{
Log.d( "Register",response.toString());
}
#Override
public void handleFault(BackendlessFault fault)
{
Log.d( "Register faild ",fault.toString());
}
});
Related
I have an app that sends data to a firebase realtime database. Another app takes the data from the database and displays it in an activity. I use the addValueEventListener so that whenever there's new data added, the second app shows it. The data is basically a name and a phone number. The problem is that when i am on the activity that displays the data and i enter data from the other app the activity crashes, because of a null pointer exception. After some logs i have discovered that the problem is that the name field is in the snapshot but the phone field is not. The database is correctly updated, so i think the problems is the fact that the second app takes data too fast from the database and does not wait for it all to be added to the database. Is this the problem? How can i solve this problem?
databaseReference.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot snapshot) {
for (DataSnapshot s: snapshot.getChildren()){
Button rent = createButton(s.child("Name").getValue().toString(), s.child("Phone").getValue().toString());
}
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
Log.i("ERROR",":C");
}
});
Found out the problem. The first app was adding the name first in the database and after the phone number. The idea is to add them together like an object.
eg. {"Name" : "Mike", "Phone":"82741241"}. This way you don't get the null pointer exception because the app adds both the name and phone and does not add first the name and triggers the addValueEventListener in the second app with an missing phone field.
Basically I want to align the messages as they are supposed to be in the usual chat app.
UPDATE: Now messages are aligned properly in the recyclerview. But whenever I send the new message it puts them on the top of the other messages. And whenever I go back and come again to that activity messages are arranged properly(even the top ones).
I just want the message which I send to show up at the bottom. Any help will be appreciated.
mLinearLayout.setReverseLayout(true);
Then:
private void loadmessage() {
mFirestore.collection("Users").orderBy("Timestamp", Query.Direction.DESCENDING).limit(10).addSnapshotListener(new EventListener<QuerySnapshot>() {
#Override
public void onEvent(#Nullable QuerySnapshot snapshots,
#Nullable FirebaseFirestoreException e) {
if (e != null) {
Log.w("TAG", "listen:error", e);
return;
}
for (DocumentChange dc : snapshots.getDocumentChanges()) {
switch (dc.getType()) {
case ADDED:
Message message = dc.getDocument().toObject(Message.class);
messageList.add(message);
mAdapter.notifyDataSetChanged();
mMessagesList.scrollToPosition(messageList.size()-10);
break;
}
}
}
});
}
You should continue retrieving the information as you are currently doing, and then invert the order on client side, it isn't an expensive task, and trying to do what you want in Firestore is not implemented yet.
After retrieving the list, you can do something like:
Collections.reverse(messageList.clone());
Here is the same case scenario and it has the answer too. So in case anyone looking for the answer.
And This is the github repository for the features of the firestore chat app.
in a Firebase Android app that I'm currently developing I would like to provide an export feature. This feature should allow the user to export a set of data that is stored in Firebase.
My plan is to gather all required data into a intermediate object (datastructure) that can be (re-)used for multiple export types.
I am running into the issue that because of the flat Firebase data structure that I am using (as explained in https://www.firebase.com/docs/android/guide/structuring-data.html), it's difficult to know when all the data required for the export has been collected.
Example: when retrieving all objects that are referenced using 'indices' (name: key, value true), for each of these I set an addListenerForSingleValueEvent listener, but because this returns asynchronous, it's impossible to determine when all the indices are retrieved. This way it's not possible to determine the correct moment to start the export.
Who has best practices for coping with this?
Posting this to show a worked out example of the comment of #FrankvanPuffelen that seems to do the job quite well:
#Override
public void onDataChange(DataSnapshot indexListDataSnapshot) {
final long participantsRequired = indexListDataSnapshot.getChildrenCount();
for (DataSnapshot ds : indexListDataSnapshot.getChildren()) {
DataUtil.getParticipantByKey( mEventKey, ds.getKey() ).addListenerForSingleValueEvent( new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
Participant p = dataSnapshot.getValue(Participant.class);
mParticipants.add( p );
if (participantsRequired == mParticipants.size()){
executeExport();
}
}
#Override
public void onCancelled(FirebaseError firebaseError) {
mListener.onDataLoadFailure( firebaseError.toException() );
}
});
}
}
Now I am using Gluon plugin and it is very helpful to start working with JavaFXPorts. I have my application ready and I can use it on computers and phones. I tested on phone with system android. Application is working good but only with my server.
I take care of the different resolutions and I think that it is good for now.
I want to have Turn-based Multiplayer Application but I have still big problem with using Google Play Service. Tutorial which show how to use this services for turn-based multiplayer application is written in pure android and use Activity. My question is maybe very simple but If I have my application view from "fxml" how to use it as an tutorial Activity?
I want to do auto-matching for my application and next I want override method takeTurn() to suit it to my application.
For example, how can I change thing like that (code below) to application in JavaFX?
I must use google services from my JavaFX(src/main/java folder) class in addition AndroidPlatformProvider.java and all methods must be in src/android/java folder. I know that I must use PlatformService and PlatformProvider. I did it as in the examples: HelloPlatform and SMSTracker .
I use methods from my interface PlatformProvider but application still crashes. :(
I only use Provider from my code of JavaFX and I don't have android Activity. I don't know how to use these method without Activity or View:
- public void onActivityResult(int request, int response, Intent data)
- public void playTurn(View view)
Can I call from google service methods to methods from my controller for view (fxml).
I don't know how these methods should working with JavaFX.
public class TbmpGameActivity extends Activity {
...
#Override
public void onActivityResult(int request, int response, Intent data) {
super.onActivityResult(request, response, data);
...
if (request == RC_SELECT_PLAYERS) {
if (response != Activity.RESULT_OK) {
// user canceled
return;
}
// Get the invitee list.
final ArrayList<String> invitees =
data.getStringArrayListExtra(Games.EXTRA_PLAYER_IDS);
// Get auto-match criteria.
Bundle autoMatchCriteria = null;
int minAutoMatchPlayers = data.getIntExtra(
Multiplayer.EXTRA_MIN_AUTOMATCH_PLAYERS, 0);
int maxAutoMatchPlayers = data.getIntExtra(
Multiplayer.EXTRA_MAX_AUTOMATCH_PLAYERS, 0);
if (minAutoMatchPlayers > 0) {
autoMatchCriteria = RoomConfig.createAutoMatchCriteria(
minAutoMatchPlayers, maxAutoMatchPlayers, 0);
} else {
autoMatchCriteria = null;
}
TurnBasedMatchConfig tbmc = TurnBasedMatchConfig.builder()
.addInvitedPlayers(invitees)
.setAutoMatchCriteria(autoMatchCriteria)
.build();
// Create and start the match.
Games.TurnBasedMultiplayer
.createMatch(mGoogleApiClient, tbmc)
.setResultCallback(new MatchInitiatedCallback());
}
}
}
or something like that:
// Call this method when a player has completed his turn and wants to
// go onto the next player, which may be himself.
public void playTurn(View view) {
// Get the next participant in the game-defined way, possibly round-robin.
String nextParticipantId = getNextParticipantId();
// Get the updated state. In this example, we simply retrieve a
// text string from the view. In your game, there may be more
// complicated state.
mTurnData = mDataView.getText().toString();
// At this point, you might want to show a waiting dialog so that
// the current player does not try to submit turn actions twice.
showSpinner();
// Invoke the next turn. We are converting our data to a byte array.
Games.TurnBasedMultiplayer
.takeTurn(mGoogleApiClient, mMatch.getMatchId(),
mTurnData.getBytes(Charset.forName("UTF-16")),
nextParticipantId)
.setResultCallback(this);
}
Latest version of the jfxmobile plugin (1.0.3) includes recent changes in Dalvik SDK that contains the port of JavaFX 8 to android.
In FXActivity class, it has been added a very convenient method to listen to results of intents: setOnActivityResultHandler().
This means you shouldn't add new activities to your app, and only use FXActivity. You should add an Intent to it, and set a proper result handler to the FXActivity.
Have a look at this recent post at Gluon's site. It explains how to access native services, based on the case of taking a picture with the device's camera, and waiting to get the result of it to resume the app.
Basically, this is what it is required in this case:
public void takePicture() {
// create intent
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
...
// Add result handler
FXActivity.getInstance().setOnActivityResultHandler((requestCode, resultCode, data) -> {
if (requestCode == TAKE_PICTURE && resultCode == RESULT_OK) {
...
}
});
// launch activity
FXActivity.getInstance().startActivityForResult(intent, TAKE_PICTURE);
}
Try this approach with your app.
I'm currently working on ListViews in Fragments. The Listviews are loaded by Cursorloader, but without ContentManager. So the code looks like this and it works:
#Override
public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
Log.d("SoapERP", "onCreateLoader");
CursorLoader loader = new CursorLoader(getActivity()) {
final DBHelper dbhelper1= new DBHelper(getActivity());
#Override
public Cursor loadInBackground() {
Cursor c = null;
dbhelper1.open();
c = dbhelper1.fetchAllMatnameswithID();
// dbhelper1.close();
return c;
}
};
return loader;
My problem is that I get an LogCat-Error-Message that the database wasn't closed. But if I use dbhelper.close(); I get the Error "Database is already closed" wich is also understandable because it is just before the return statement. After the return statement code is not reachable and if I declare DBHelper dbhelper1 final the program crashes without any information in logcat. So what is my fail???
Finally I found here the right statement as of Dianne Hackborn from android framework development: "A content provider is created when its hosting process is created, and remains around for as long as the process does, so there is no need to close the database -- it will get closed as part of the kernel cleaning up the process's resources when the process is killed. Dianne Hackborn Android framework engineer hack...#android.com " - so let's use Content Provider.