picoe/Eto

[Mac] gridview gets and draws all cells horizontally out of view

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#1,529 opened on Dec 5, 2019

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help wanted

Description

Expected Behavior

When the mac gridview loads and gets cells to display/draw, it should only do this for the visible cells.

Actual Behavior

The mac gridview seems to load and draw all the cells horizontally out of view, but not vertically out of view.

Info

When loading data in to a 300/300 size gridview with a column count of 60 and a row count of 10,000 with varying complex cells, it takes quite a while to load. When loaded, it seems that scrolling horizontally does not cause the table cell views to load/be drawn. Almost like they have already been drawn. This can cause massive performance drops to the mac gridview with many columns as it tries to get the data for all columns while scrolling vertically.

Solution

Only get/draw cells that are visible in the gridscrollview

Steps to Reproduce the Problem

  1. Create grid of any size
  2. Give it 60+ columns, 10000+ rows and cells of varying complexity. ~complex being an imageviewcell
  3. Launch app and see the performance issues mentioned above.

Specifications

  • Version: latest
  • Platform(s): mac, xammac2
  • Operating System(s): any mac OS

Contributor guide

Tech stack
csharp
Domain
desktopperformance
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
familiarity with Eto grid renderingbasic understanding of Mac platform rendering
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
35
Research direction
Investigate the Mac gridview implementation in Eto, likely in the file GridView.mac.cs or similar. Focus on how cells are loaded and drawn during scrolling. Compare the horizontal and vertical scrolling behaviors to understand why all cells are rendered horizontally but not vertically. Check if there is a missing visibility check for horizontal scrolling that causes performance issues. Look at the GridScrollView or related classes to see if only visible cells are requested.
[Mac] gridview gets and draws all cells horizontally out of view · picoe/Eto#1529 | Good First Issue