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Hello!
I'm testing an application that uses PackageCatalog.Uninstalling event and i would like to change the UI when this event is triggered but when i try to do it an exception is given.
I also tried with a dispatcher but received another error
Hello @Andre Luiz Bacelar Gonçalves de Menezes ,
Welcome to Microsoft Q&A!
According to the error message, the window has not been created yet. Please manipulate UI after all UI are loaded.
Thank you.
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(316.8, 62%, 40%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EAR%3C/text%3E%3C/svg%3E)
Hello @Junjie Zhu - MSFT . I'm with Andre in this issue. The window is already created. Our screen is completely loaded and after some minutes we uninstall a package and then this issue occurs.
Could you please tell us whether you are using the Blank app,Packaged (WinUI3 in Desktop)? And which package are you trying to uninstall? The main app package or the other optional packages?
Could you please provide a minimum sample to help us reproduce the issue?
@Jeanine Zhang-MSFT @Junjie Zhu - MSFT
Here is the source code used:
https://drive.google.com/file/d/16bcV4U40CBBZCPScxf3aQRrVZhEhhkAe/view?usp=sharing
The package used for installed and uninstalled: PDF X: PDF Editor & PDF Reader.
If we change an element x:bind to .xaml, the error always occurs , but if we change a local variable, works well.
I ran the app and after loaded I uninstall the PDF X: PDF Editor & PDF Reader. Then, a ComException happens into PackageCatalog_PackageUninstalling event.
Sorry for the late reply. Due to my work environment policy, I couldn't open the link to the code you shared. Could you please provide the minimum sample via the GitHub?
Hello! The code was also given by image on the comment made by @Anderson Rodrigues Cavalcante the issue is the same as the original question
Hello!
The images of the given code was also shared by Anderson on his reply
Could you please share the code in a code format instead of the image?
Could you please reproduce the issue in a blank project and share a minimum sample to help us reproduce the issue?
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(211.20000000000002, 92%, 30%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3ERL%3C/text%3E%3C/svg%3E)
Any updates about this issue?
Hello @Andre Luiz Bacelar Gonçalves de Menezes and @Anderson Rodrigues Cavalcante ,
Welcome to Microsoft Q&A!
According to the error message, the window has not been created yet.
When uninstalling this app, the UI will be closed first, and then the packageCatalogUninstalling event will be triggered, so you will get an error when accessing the UI in the packageCatalogUninstalling event. This is an expected behavior because all UIs are destroyed.
Thank you.
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@Junjie Zhu - MSFT thank you for your reply.
Did you implement the code I shared? The application that we are being uninstalled is not the application that is running, it is another. I have my sample XPTO and I am uninstalling the PDF X: PDF Editor & PDF Reader. There is no relation to my sample XPTO.
However, I found a component called SynchronizationContext and a method called Post. This way, it fixed the error.
Thank you.