Drop Down Form No Showing Value in Table

[gyongue1]

PowerApps Form with several drop downs. In view/edit mode of the form it does not show the value from the corresponding table. The other two drop downs show the correct details. All three will update the record as expected. I have gone through every setting and cannot figure out what I am missing. 

Form DataSource: tbl_InvItem

Item: galInvItem.Selected

Drop Down 1 for Category (works fine):

Card Default: ThisItem.InvItemCateg_ID

DD Default: "1"

Items: tbl_InvItemCateg

Drop Down 2 for Units (works fine):

Card Default: ThisItem.Units_ID

DD Default: "1"

Items: tbl_Units

Drop Down 3 for Dose Units (doesn't work)

Card Default: ThisItem.InvItemDoseUnits_ID

DD Default: "1"

Items: tbl_InvItemDoseUnits

What other values should I look at? I've tried deleting and reinputting the datacard, but that didn't work. 

Thanks!

[RandyHayes]

@gyongue1 

Your dropdowns are not going to show the record values because the Default property on all of them is 1.

If this is in a Form, then they should be Parent.Default

I hope this is helpful for you.

[gyongue1]

I tried that and I get the same result. The first two show the values and the final one doesn't regardless of whether I used "1" or Parent.Default.

[RandyHayes]

@gyongue1 

What is the Default of the Datacard that the last dropdown control is in?

[RandyHayes]

@gyongue1 

Never mind...I see that you provided that already as I re-read.

What kind of column is InvItemDoseUnits_ID ?

[gyongue1]

ThisItem.InvItemDoseUnits_ID

All the Defaults for the Datacards are ThisItem......

[gyongue1]

int, but I double checked and all three are int.

Could it have something to do with it coming from a Gallery selection?

[RandyHayes]

@gyongue1 

And what is in the underlying record DOES match some record with the column displayed from the tbl_InvItemDoseUnits source?

A couple of troubleshooting steps:

1) Place a label IN the datacard with your dropdown and set the Text to:  ThisItem.InvItemDoseUnits_ID

    Observe what this shows...is it what you expect?

2) Change the Text property of the label to:  LookUp(tbl_InvItemDoseUnits, theColumn = ThisItem.InvItemDoseUnits_ID, true)

    Replace "theColumn" with the name of the column you are displaying in the dropdown.  

    This label should show true if there is a match (which means the dropdown should match too)

[gyongue1]

Thanks for your help so far. I just realized it was only showing the first position of what was in the drop down (I have a blank value for the units field at the top position). It just happened that the other two drop down values happen to be those in the first position and I didn't think to change those values to see what it would bring back.

[gyongue1 · Accepted solution]

I figured it out by using ShowColumns for Items and LookUp for Default and then changing the Update for the DataCard. @RandyHayes, thank you for your responses which results in me double checking other things!