Answered

Setting inital variable

(0) Share

Report

Posted on by Community Power Pla... Microsoft Employee

I use an app with a local variable and want to set that variable to NOTHING or NULL or "" (not sure which to use yet) on the start of the application. I put this varForm="" in the OnStart and it did not do anything. I then put it in the OnVisible and still did not do anything. Where in the properties should this go and is there such as thing as thisVar=NOTHING?

Thanks

Categories:

Building Power Apps

I have the same question (0)

All responses (12)

Answers (1)

Sort by

Sienna 1,532 on at

Like (0)

Report
Copy link

Link copied!

I'm afraid you will have to give us more information about the variable. If the variable is is used in your app as numeric and in one page then use
UpdateContext({varForm:0}); UpdateContext({varForm:Value("")})
or if the variable is in text format and used in one screen
UpdateContext({varForm:" "}); UpdateContext({varForm:""})
or in case the variable is global used in multiple pages set as text
Set(varForm," "); Set(varForm,"")
or in case the variable is global used in multiple pages set as numeric
Set(varForm,0); Set(varForm,Value(""))

Was this reply helpful? Yes No
Meneghino 6,949 on at

Like (3)

Report
Copy link

Link copied!

The OnStart will fire only once when the app is opened, hence you need to modify the property then save, close and re-open the app for it to work.
Nulls are a pain in PowerApps, please see this post.

Was this reply helpful? Yes No
Community Power Pla... Microsoft Employee on at

Like (0)

Report
Copy link

Link copied!

Sienna,

It is a text variable. I have only one screen and one form, but based on a few different buttons, I am showing or hiding different data cards and I want the app to always begin with the "Personal" tab (or button). I tried using UpdateContext, but got an error about it being a global variable. So I tried using Set(varForm,Value"")) and it gives me Invalid Argument Type. However, if I do Set(varForm,Text("")) it seems to work, but when I run the app it does not reset the variable's value.

Was this reply helpful? Yes No
Sienna 1,532 on at

Like (0)

Report
Copy link

Link copied!

Therefore you have to reset it with other value as I wrote it above.
Set(varForm,Text("whatever"));Set(varForm,Text(""))

But if you using it in one screen then use UpdateContext !!!!

UpdateContext({varForm:"whatever"}); UpdateContext({varForm:""})

Was this reply helpful? Yes No
Community Power Pla... Microsoft Employee on at

Like (0)

Report
Copy link

Link copied!

It is interesting that the app only uses one screen and I am trying UpdateContext again, but it is giving me an error about the variable being global. So I am using Set(varForm,Text("Personal"));Set(varForm,Text("")) and it does not error, but it is not setting the variable either and retaining a prior value.

Ultimately what I want is when the app opens, set the variable to the text value "Personal" and show those data cards whose visible property is true when varForm value is "Personal". I want a new user opening the app to land on that screen each time.

Was this reply helpful? Yes No
Sienna 1,532 on at

Like (0)

Report
Copy link

Link copied!

It is interesting that the app only uses one screen and I am trying UpdateContext again, but it is giving me an error about the variable being global.
That is because you have somewhere in your app used that variable and seting it with "set" funftion
So I am using Set(varForm,Text("Personal"));Set(varForm,Text("")) and it does not error, but it is not setting the variable either and retaining a prior value
Send a picture of your tab gallery with all your code in it and a datasource link to your tab to be able to help you more with this issue

Was this reply helpful? Yes No
Sienna 1,532 on at

Like (0)

Report
Copy link

Link copied!

meanwhile you can check this thread for default selecting the tab

https://powerusers.microsoft.com/t5/General-Discussion/Select-a-Gallery-item-on-screen-visible/m-p/80564#M31413

Was this reply helpful? Yes No
Community Power Pla... Microsoft Employee on at

Like (0)

Report
Copy link

Link copied!

This is a snip of the "tool bar" I am using. What I am trying to do is avoid using a PATCH statement. Recently I saw someone use this "tab" environement and one screen and one form to show and hide datacards. The dataset is a Sharepoint list.

When a button is selected, I am using the OnSelect in this context: Set(varFormTab="Personal") for the btnPersonal; Set(varFormTab="Medical") for the btnMedical, and so on. So yes, I am using the Set keyword. Should I use UpdateContext instead?

Was this reply helpful? Yes No
Verified answer

Sienna 1,532 on at

Like (0)

Report
Copy link

Link copied!

If you are using it in one screen then definitely change it witch local variable that means UpdateContext with proper syntax as I mentioned it above
UpdateContext({varFormTab:"Personal"})

And remove all your set function because you have wrong syntax there
Set(varFormTab="Medical") - is wrong syntax

Was this reply helpful? Yes No
Community Power Pla... Microsoft Employee on at

Like (0)

Report
Copy link

Link copied!

Thank you. This seems to work

Was this reply helpful? Yes No