WinForms: How to Prevent Flickering When Updating a Panel with Multiple Controls Dynamically
I'm optimizing some code but I'm working on a personal project and I've been banging my head against this for hours....... I'm facing an issue with flickering when I dynamically update a Panel in my WinForms application which contains multiple controls. The application is built using .NET Framework 4.8. When I add or remove controls from the Panel during runtime, the flickering becomes quite noticeable, especially when the Panel has a lot of custom drawings and nested controls. I've tried setting the `DoubleBuffered` property of the Panel to `true`, but it doesn't seem to make a significant difference. I also attempted to wrap the control updates in `BeginUpdate` and `EndUpdate`, but that didn't resolve the flickering either. Here's a snippet of the code I'm currently using to update the Panel: ```csharp private void UpdatePanelControls(List<MyCustomControl> newControls) { panel1.SuspendLayout(); // Attempt to prevent flickering panel1.Controls.Clear(); // Clear existing controls foreach (var control in newControls) { panel1.Controls.Add(control); } panel1.ResumeLayout(); // Resume layout panel1.Invalidate(); // Invalidate to force redraw } ``` Despite the use of `SuspendLayout` and `ResumeLayout`, there's still a noticeable flicker when this function is called, particularly if it’s invoked multiple times in a short period. The flickering seems to be worse when the controls have complex custom rendering logic. I've also checked the performance of the drawing logic, and while it does take some time, it doesn’t seem to be the main cause of the flickering. Is there a better approach to updating the Panel that could help reduce or eliminate the flickering? Any insights or best practices for handling dynamic control updates in WinForms would be greatly appreciated. For context: I'm using C# on Linux. Is there a better approach? This is part of a larger web app I'm building. I'd really appreciate any guidance on this. I'm working on a application that needs to handle this. My development environment is Windows 11. Am I missing something obvious?