starred/terminal
1
0
Fork 0
mirror of https://github.com/microsoft/terminal.git synced 2026-02-03 21:25:34 +00:00
Code Issues 19.0k Packages Projects Releases 20 Wiki Activity

[PR #9487] Fix wrong item template selection in CmdPal #27604

New Issue
Open
opened 2026-01-31 09:22:57 +00:00 by claunia · 0 comments
claunia commented 2026-01-31 09:22:57 +00:00
Owner
Copy Link

Original Pull Request: https://github.com/microsoft/terminal/pull/9487

State: closed
Merged: Yes

PR Checklist

Detailed Description of the Pull Request / Additional comments

There seems to be a bug in WinUI (see microsoft/microsoft-ui-xaml#2121)
that results in heterogeneous ModernCollectionBasePanel configured
with DataTemplateSelector and virtualization enabled
to recycle a container even if its ContentTemplate is wrong.

I considered few options of handling this:

  • Disabling virtualization (by replacing item container template with
    some non-virtualizing panel (e.g., StackPanel, VirtualizingStackPanel
    with VirtualizationMode=Standard)
  • Replacing DataTemplateSelector approach with ChoosingItemContainer
    event handling approach, which allows you to manage the
    item container (ListViewItem) allocation process.

I have chosen the last one, as it should limit the amount of allocations,
and might allow optimizations in the future.

The solution introduces:

  • A container for ListViewItems in the form of a map of sets:
    • The key of this map is a data template (e.g., TabItemDataTemplate)
    • The value in the set is the container
  • ChoosingItemContainer event handler that looks for available
    item in the container or creates a new one
  • ContainerContentChanging event handler that returns the
    recycled item to the container
**Original Pull Request:** https://github.com/microsoft/terminal/pull/9487 **State:** closed **Merged:** Yes --- ## PR Checklist * [x] Closes https://github.com/microsoft/terminal/issues/9288 * [x] CLA signed. * [ ] Tests added/passed * [ ] Documentation updated. * [ ] Schema updated. * [ ] I've discussed this with core contributors already. ## Detailed Description of the Pull Request / Additional comments There seems to be a bug in WinUI (see microsoft/microsoft-ui-xaml#2121) that results in heterogeneous `ModernCollectionBasePanel` configured with `DataTemplateSelector` and virtualization enabled to recycle a container even if its `ContentTemplate` is wrong. I considered few options of handling this: * Disabling virtualization (by replacing item container template with some non-virtualizing panel (e.g., `StackPanel`, `VirtualizingStackPanel` with `VirtualizationMode`=`Standard`) * Replacing `DataTemplateSelector` approach with `ChoosingItemContainer` event handling approach, which allows you to manage the item container (`ListViewItem`) allocation process. I have chosen the last one, as it should limit the amount of allocations, and might allow optimizations in the future. The solution introduces: * A container for `ListViewItem`s in the form of a map of sets: * The key of this map is a data template (e.g., `TabItemDataTemplate`) * The value in the set is the container * `ChoosingItemContainer` event handler that looks for available item in the container or creates a new one * `ContainerContentChanging` event handler that returns the recycled item to the container
claunia added the pull-request label 2026-01-31 09:22:57 +00:00
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
⛺ Reserved
A11yCO
A11yMAS
A11ySev1
A11ySev2
A11ySev3
A11yTTValidated
A11yUsable
A11yVoiceAccess
A11yWCAG
Area-Accessibility
Area-AtlasEngine
Area-AzureShell
Area-Build
Area-Build
Area-Chat
Area-CmdPal
Area-CodeHealth
Area-Commandline
Area-CookedRead
Area-DefApp
Area-Extensibility
Area-Fonts
Area-GroupPolicy
Area-i18n
Area-Input
Area-Interaction
Area-Interop
Area-Localization
Area-Output
Area-Performance
Area-Portable
Area-Quality
Area-Remoting
Area-Rendering
Area-Schema
Area-Server
Area-Settings
Area-SettingsUI
Area-ShellExtension
Area-ShellExtension
Area-ShellExtension
Area-Suggestions
Area-Suggestions
Area-TerminalConnection
Area-TerminalControl
Area-Theming
Area-UserInterface
Area-VT
Area-Windowing
Area-WPFControl
AutoMerge
Blocking-Ingestion
Culprit-Centennial
Culprit-WinUI
Disability-All
Disability-Blind
Disability-LowVision
Disability-Mobility
External-Blocked-WinUI3
Fixed
Gathering-Data
good first issue
HCL-E+D
HCL-WindowsTerminal
Help Wanted
Impact-Compatibility
Impact-Compliance
Impact-Correctness
Impact-Visual
In-PR
InclusionBacklog
InclusionBacklog-Windows TerminalWin32
InclusionCommitted-202206
Issue-Bug
Issue-Docs
Issue-Feature
Issue-Feature
Issue-Question
Issue-Samples
Issue-Scenario
Issue-Task
Needs-Attention
Needs-Author-Feedback
Needs-Bisect
Needs-Discussion
Needs-Repro
Needs-Tag-Fix
Needs-Tag-Fix
Needs-Triage
No-Recent-Activity
Priority-0
Priority-1
Priority-2
Priority-3
Product-Cmd.exe
Product-Colortool
Product-Colortool
Product-Colortool
Product-Conhost
Product-Conpty
Product-Meta
Product-Powershell
Product-Terminal
Product-WSL
pull-request
Mirrored from GitHub Pull Request
 Resolution-Answered
Resolution-By-Design
Resolution-Duplicate
Resolution-External
Resolution-Fix-Available
Resolution-Fix-Committed
Resolution-No-Repro
Resolution-Won't-Fix
Severity-Blocking
Severity-Crash
Severity-DataLoss
spam
this-will-be-a-breaking-change
Tracking-External
WindowsTerminal_Win32
Work-Item
zAskModeBug
zInbox-Bug
No Label pull-request
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
claunia
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: starred/terminal#27604
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?