Bug 40997 - Toggle WindowsForms form into fullscreen not working in Linux
Summary: Toggle WindowsForms form into fullscreen not working in Linux
Status: NEW
Alias: None
Product: Class Libraries
Classification: Mono
Component: Windows.Forms ()
Version: 4.2.0 (C6)
Hardware: PC Linux
: --- normal
Target Milestone: Community
Assignee: Bugzilla
Depends on:
Reported: 2016-05-10 16:40 UTC by Leonid Vasilyev
Modified: 2017-09-01 11:56 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Leonid Vasilyev 2016-05-10 16:40:58 UTC
I use Mono 4.2.3, Ubuntu 14.04 LTS. Reproduced always both on 32-bit and 64-bit Ubuntu.

Steps to reproduce:
1. Create WindowsForms application with single form and toggle fullscreen using TopMost, FormBorderStyle and WindowState form properties:

using System;
using System.Windows.Forms;

static class Program
    static void Main()
        var ui = new Form();
        ui.TopMost = true;
        // Order of the following assignments is important on Windows.
        ui.FormBorderStyle = FormBorderStyle.None;
        ui.WindowState = FormWindowState.Maximized;

2. Run application with mono app.exe

Actual result:
Form window is maximized, but unity launcher and top bar are still visible

Expected result:
Form window is maximized and fully cover unity launcher and top bar as it cover task bar in Windows
Comment 1 Leonid Vasilyev 2016-05-10 16:46:36 UTC
I was able to toggle fullscreen on Linux only by using 3rd party util called wmctrl (http://linux.die.net/man/1/wmctrl):
var toggleFullscreen = new Process
    StartInfo = new ProcessStartInfo
        FileName = "wmctrl",
        Arguments = $"-r :ACTIVE: -b toggle,fullscreen",
        CreateNoWindow = true