When I click my rate_btn to start this transaction function.
It works fine but in the process it re-run my class activity one more time (my class activity re-runs every time transaction is used) therefore resetting everything like my msg_ID.
For example, my msg_ID changes (due to using random) every time this class activity is called, so when I run transaction it works but in return it ran the class activity also therefore changing my msg_ID aswell.
Here's a scenario:
so when click this "rate" button it does the rating
on the current msg_ID but when I click on it again, it rates a different
msg_ID because of my get random msg_ID. I think this is caused when
I call the onComplete method.
When I click the rate_btn
Now the class re-run and I click on the rate_btn again.
It votes up the first msg_id then when I click the rate_btn again it votes up the second key (Because of it re-called class activity and the msg_id changed)
Here's the code for transaction:
rate_btn.setOnClickListener(new OnClickListener(){
public void onClick(View v){
Firebase upvoteref = new Firebase("https://myapp.firebaseio.com/"+msgID+"/upvotes");
upvoteref.runTransaction(new Transaction.Handler() {
@Override
public Transaction.Result doTransaction(final MutableData currentData) {
if (currentData.getValue() == null) {
currentData.setValue(1);
} else {
currentData.setValue((Long) currentData.getValue() + 1);
}
return Transaction.success(currentData);
}
public void onComplete(FirebaseError firebaseError, boolean committed, DataSnapshot currentData) {
if (firebaseError != null) {
System.out.println("Firebase counter increment failed.");
} else {
System.out.println("Firebase counter increment succeeded.");
}
}
});
}
Here is the code for retrieving the random id:
String msgID; //this variable is declare at the start of the class as a global variable.
Firebase ref = new Firebase("https://myapp.firebaseio.com/"+msgID);
ref.addValueEventListener(new ValueEventListener() {
public void onDataChange(DataSnapshot snapshot) {
Iterable<DataSnapshot> ds = snapshot.getChildren();
//getting maximum number of children
long allNum = snapshot.getChildrenCount();
int maxNum = (int)allNum;
//getting the random integer from number of children
int randomNum = new Random().nextInt(maxNum);
Iterator<DataSnapshot> ids = ds.iterator();
int count = 0;
//has next will check if there are values in the next iteration , while count is used as a position substitute.
while(ids.hasNext() && count < randomNum) {
ids.next();
count ++; // used as positioning.
}
Map<String, Object> newPost = (Map<String, Object>) ids.next().getValue(); // ids will take the value in the iterator (iterate at key)
//getting the message from the key
msgID = newPost.get("id").toString();
}
Any ideas?
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