IssueTracker

Oh and one more thing I forgot. Fragment A's child fragment is also part of the nested navigation controller, for which the Fragment A contains the root NavHostFragment, and not the root nav controller Fragment A is part of. So maybe it's not due to FragmentManager, maybe it's the nested navigation controller prematurely removing it's own fragment, when exitAnimation starts for it's root/parent fragment A.

Other than that, instanceState of the child fragment is preserved properly when navigating back and forth.. It's just that it's view is removed prematurely for some reason.

Ok I just tested it, and it is due to nested navigation graph. When I include a child fragment directly into Fragment A, without navigation, it's not removed prematurely and it's working as intended.

So where do we go from here, is this a bug for you to fix, or there's something wrong with my nested navigation graph implementation, in which case I'd like you to point me in the right direction how to fix it?

Can you attach a sample project that reproduces your issue?

Here you go: https://drive.google.com/file/d/12Tz8YjCEbcs4LzxqL4352zUJyPvJ_GLt/view?usp=sharing

I slowed down the animations so you can see what's happening.

Root Fragment A is the one with BottomNavigationBar on the bottom.
GREEN - Fragment A's CHILD fragment (the one that's disappearing)
RED - Destination Fragment

Press "Settings" in the action menu on the upper right to start navigation. Observe how Root Fragment A is visible during the whole animation with it's BottomNavigationBar, but it's CHILD GREEN fragment disappears immediately, as it is part of the nested navigation graph hosted in the Fragment A itself.

On the way back, Fragment A is properly recreated with it's green child fragment, and both are visible properly (when going back in the direction A <- B).

I'm having trouble downloading your project from Google Drive for some reason. Would you mind attaching it here directly?

I suspect this is a Fragment issue and not something Navigation can control. I'd be interested to know if you run into the same issue if you have *any* Fragment, rather than a NavHostFragment, between your child of A and A itself.

I'll test that too when I have some time, though it might not be soon.

I'll attach the project directly so you can test it yourself, and if it is the problem with Fragments, then let's open the issue for Fragments..

Thanks, we've confirmed this is a problem with Fragments and have marked it as a duplicate of the relevant Fragment issue.

Project: platform/frameworks/support
Branch: androidx-master-dev

commit c53170c58309d7370d63d5386e83fce4cee02ba2
Author: jbwoods <jbwoods@google.com>
Date:   Wed Jun 26 17:58:38 2019

    Avoid grandchild Fragment animations running during parent Fragment transactions
   
    Follow-up to aosp/951635. Child fragment views are not destroyed when the parent
    is animated, but grandchild fragment views are.
   
    This change checks up the ancestor hierarchy to ensure fragment views
    will not be destroyed if any of its ancestors are being removed.
   
    Test: Added unit Test
    BUG: 116675313
    Change-Id: Ie65ae2fb150340b51bb0362cfa84f320ee2e8c7e

M       fragment/fragment/src/androidTest/java/androidx/fragment/app/FragmentAnimationTest.kt
M       fragment/fragment/src/main/java/androidx/fragment/app/Fragment.java
M       fragment/fragment/src/main/java/androidx/fragment/app/FragmentManagerImpl.java

https://android-review.googlesource.com/1001542
https://goto.google.com/android-sha1/c53170c58309d7370d63d5386e83fce4cee02ba2

This has been fixed internally and will be available in the Fragment  1.2.0-alpha01 release.

This actually just missed the 1.2.0-alpha01 cut off, so it'll actually be in 1.2.0-alpha02.

Can confirm fix in "androidx.fragment:fragment:1.2.0-alpha02". Thanks a lot!

Yes please - I have a goto last row but it only runs on open; would be great to run on every tab/sheet change

Come on... I was happy to see the way Google implemented apps vs MS vba and decided to convert several off my office documents to google sheets, but there is no way this is going to happen without support for this "onSheetChange" feature. It really makes me wonder how many  other basic features are missing in sheets. It only took 10 min. of investigation to put sheets on hold....

I have a sidebar that shows filters for the active sheet - when you change the sheet I need to reconfigure my sidebar.

At the moment I use a mouse-over event on my sidebar AND a timer function to constantly monitor the current sheet.

It would be so much better if there were a trigger on sheet change.

Thanks

Really need this feature and it seems like something that would be very simple to implement.  Knowing the current sheet is crucial for lots of operations and constantly checking that it hasn't changed seems very wasteful.

Need this, too

One and a half year, no update yet...

Oh come on Google folks!  Surely you can incorporate this!  Soooooooooo many people want this and really need it!

up

+

+

Please Google team - this would be very helpful!!

+

+

Hello?  Can't believe this hasn't been added yet.

Is this getting added ? Google team are you guys listening?

I really need this trigger. Please add. Is anyone responding to this request?

There is at least 1 workaround posted about that I know of if anyone is desperate. It's a bit pffft though based on a timer from memory. I'm not that desperate ...

I haven't actually tried them & I know some voters here may even be the contributors but in case anyone is frazzled for a workaround & hasn't come across them, even if a bit hacky >>
https://stackoverflow.com/questions/38160116/trigger-when-user-switches-between-sheets
https://webapps.stackexchange.com/questions/91812/how-can-i-trigger-a-function-when-switching-sheets-within-a-spreadsheet

+

need it also

+

+

Needed

On change sheet would be very useful

Really needed.

Needed. I want to reset something as soon as a particular sheet is viewed.

Come on Google, this has been around for years ... would give greater control of the user experience if changing sheets causes an action.

This will be a great feature. thanks

YESSSSS THIS !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Thanks for your input @gr...@velvet-dps.tech. However, if I would do as you suggest and create that dictionary in CacheService or Properties is it possible to fire a trigger when this dictionary is changed such that my desired function would run immediately e.g. make active cell matching the last one cell in the last row of the active sheet after a user in the gsheet changes the tab?

I would like it too!

This would be useful for addon script to be able to detect which sheet is active and adjust content in the addon based on the current sheet.

I need this feature as well! It was available in Excel Macros and I'm converting scripts to Google sheets

Waiting!!

Solved:
https://tanaikech.github.io/2020/05/18/change-tab-detection-on-google-spreadsheet-using-onselectionchange-event-trigger-with-google-apps-script/

Thanks for the tutorial on how to use onSelectionChange!

However there is one thing that does not work for me. I would like to activate a specific cell when switching tabs. For some reason the function SpreadsheetApp.setActiveRange(activeRange) does not work within onSelectionChange(e). Interestingly, the functionality of SpreadsheetApp.setActiveRange(activeRange) does work when used within onOpen(e). Any idea on why that is the case?

please google, add this trigger for us

Here is my work-around for onSheetChange:


function saveActiveSheet() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var actsheet = ss.getActiveSheet();
  // The onSelectionChange() function executes in a separate thread
  // which does not use any script global variables, so use the
  // PropertiesService to maintain the user global state.
  var userProperties = PropertiesService.getUserProperties();
  userProperties.setProperty('ACTIVE_SHEET', actsheet.getSheetName());
}

function onSheetChange(e) {
  // Do anything needed after a new sheet/tab selection

}

function onSelectionChange(e) {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  // Get current sheet name and compare to previously saved sheet
  var currentactsheet = ss.getActiveSheet();
  var currentactsheetname = currentactsheet.getSheetName();
  var userProperties = PropertiesService.getUserProperties();
  var actsheetname = userProperties.getProperty('ACTIVE_SHEET');
 
  if (currentactsheetname !== actsheetname) {   // New sheet selected
    saveActiveSheet();
    onSheetChange(e);   // Call custom sheet change trigger
  }
  // Do anything needed when a different range is selected on the same sheet
  else {
    var range = e.range;

  }
}

function onOpen(e) {
  saveActiveSheet();
}

agreed this would be very helpful.

Much needed, Google please update

Ditto! (would be a very helpful trigger.)

Agreed!

Very much needed functionality.

I could definitely do with this please.

Would like this trigger as well... It is needed!

Same here, onSelectionChange doesn't always work. So, i need this trigger

I need this

agreed this would be very helpful.

+1

Very much needed.

Very much needed. I don't know why this trigger doesn't exist yet.

I hope google sheets will come up with this.

Looking for this feature for my implementation as well.
Want to refresh the add on sidebar when the sheet tab changes.
Since OnSelectionChange is simple trigger, it doesn't allow running showSidebar function.

+1

Please implement this asap, this is very much needed, especially for product development.