How many times a Firebasedb.GotValue can be used in blocks

Rashid

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Dec 25, 2019, 12:57:07 PM12/25/19

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I am facing problems while retrieving the data from Firebase. Beacuse Got values can be used only with getvalue and G. Is there ot Value event can be used only once the same is with the get list also. Is there any workaround?

ABG

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Dec 25, 2019, 4:00:56 PM12/25/19

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Have you studied FireBase Data Design yet?

Does it answer your question?

ABG

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Dec 25, 2019, 4:02:35 PM12/25/19

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Also, have you seen the FireBase section of FAQ

https://sites.google.com/view/ai2-faq-view/home

?

ABG

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Dec 25, 2019, 5:27:03 PM12/25/19

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I'm not sure what exactly you were asking, and no one else seems around to answer, so here's an answer to a commonly asked question:

If you get only one .Gotvalue event block per FireBaseDB component, how do you

decide what the data is and how to deal with it?

The answer (just tested by me) is to make extra copies of your

FireBaseDB component with the same attributes, but different

component names to remind you which piece(s) of data and which contexts they handle.

In the attached example, I used separate components for customer email and customer

phone requests (a very small grained choice, I admit) with extended tags built up with JOINs

to keep the data separate in the database.

Notice how I request both email and phone in the last button, and

their arriving values magically are handled separately by different event blocks.

If I were working with only one FireBaseDB component, I would have had to add

extra blocks in the .GotData event to examine the incoming tag and route the value

to the proper GUI .Text field.

Another note about tag design:

Using '/' in a tag breaks the tag list off at the first / level.

So keep your customer list separately, and don't

expect to gather it from a taglist.

Other designs might change the bucket on the fly, but I am not experienced in that.

Does this answer your question?

ABG

when fdbCustEmail GotValue.png

when btnCustEmail Click.png

when fdbCustPhone GotValue.png

when btnGetCustPhone Click.png

blocks.png

Capture ABG email and phone.PNG

Capture Rashid email.PNG

Designer components.PNG

when btnGetEmailAndPhone Click.png

TimAI2

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Dec 25, 2019, 5:38:08 PM12/25/19

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Use an if/else if block and test for the tag

Rashid

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Dec 30, 2019, 1:04:49 PM12/30/19

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Thanks.

Rashid

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Dec 30, 2019, 1:26:34 PM12/30/19

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How?

I have four tags duedate, subject, task and status each have a value input by an user (a teacher) Example values are 10-01-2020, Social Studies Task Description, Pending.

In data design these value tag pair are under the parent Assignments.

My App has an objective that whenever students logins, he is moved to student screen where he can saw the list of assignment given to him and when he clicks each item in the list (spinner). The tags and corresponding values for the assignment is displayed on the screen. But even though it is displaying the values, it is running a runtime error.

Lable9displays all the data clearly but other lables does not.

TimAI2

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Dec 30, 2019, 1:44:42 PM12/30/19

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This one is about data structure as much as anything else.

1. How do you identify the student, by their mobile phone number only, no name ?

2. Why not store all their (the student) data in one record, one tag, then you can call all of this back as a list ?

3. You haven't used the if/else blocks to define what to do when a tag is called

If you can provide all the fields for a student/students that would go into their records, I will see if I can work up an example for you.

So far I have:

["mobile",["date","subject","task","status"]]

ABG

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Dec 30, 2019, 1:47:32 PM12/30/19

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Do you read what you code?

Auto Generated Inline Image 2.png

TimAI2

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Dec 31, 2019, 4:39:21 AM12/31/19

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@ Rashid

To actually answer your question; "How to call multiple values from Firebase" - see blocks image

TimAI2

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Dec 31, 2019, 10:02:16 AM12/31/19

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We are moving!

For future questions please sign up and use the new community here:

https://community.appinventor.mit.edu/

Closing....

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