xamarin/Xamarin.Forms

Flexlayout flickers when remove child

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#3,961 opened on Oct 1, 2018

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Description

Sample

[XamarinFlexLayoutVideoIssue.zip] ** video play frame rate is slowed down (https://github.com/xamarin/xamarin-forms-samples/files/2433731/XamarinFlexLayoutIssue.zip)

[FlexLayoutSample.zip] (https://github.com/xamarin/xamarin-forms-samples/files/2433751/FlexLayoutSample.zip)

Description

FlexLayout flickers when removing a child from it

  • Notice the last second in the attached video, you will see the flexlayout expands to fill the page, and then goes back to correct height.

Steps to Reproduce

1.Open the sample and click on Experiment 2.Change the wrap property to FlexWrap.Wrap 3.Add items to be in multi line 4.Remove items

Expected Behavior

The child should be removed smoothly without flickering

Actual Behavior

FlexLayout flickers when removing from the FlexLayout Children

Information

  • IDE and IDE version: Visual Studio 2017 v15.6
  • Platform with the issue:
    • iOS: tested on 12.0
    • Android: tested on 8.0
  • Device or simulator/emulator: simulator and device

Contributor guide

Research direction
Investigate FlexLayout's layout invalidation and measure pass when removing a child. Look for timing issues or double layout passes causing flicker.
Tech stack
csharp
Domain
mobile
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C#Xamarin.Forms
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
55