I have an game as an Winform in Full Screen (no borders), maximized. But I want to present them on an different screen, like a beamer and control it on the original screen, so I need the same screen, opened twice:
One at my own screen Maximized, no borders
One at the second screen, normal state with title bar.
I'm quite sure, I'm thinking about this too easily. What I tried is:
new game().Show();
new game().Show(WindowState = FormWindowState.Normal));
But then It says:
Argument 1: cannot convert from 'System.Windows.Forms.FormWindowState' to 'System.Windows.Forms.IWin32Window'
So, is this hard to do?
Try this:
game g1 = new game();
g1.Show();
game g2 = new game();
g2.WindowState = FormWindowState.Normal;
g2.Show();
What you tried doesn't work because Form.Show() expects either nothing or another IWin32Window (typically another Form) as an argument, and you're passing a FormWindowState.
Note that, while this shows you how to open two forms of the same class with different window states, it doesn't show you how to make two different forms show the same game content at once, which will be much more involved.
Related
In a Winforms app, I followed the general guidance in how-to-write-winforms-code-that-auto-scales-to-system-font-and-dpi-settings and in .Net Framework high-dpi support to enable PerMonitorV2 DPI Scaling. I am using .NET Framework 4.8 on a system post Windows 10 Anniversary Update (1607) to make use of the latest high DPI support features.
The DPI scaling looks great if the app is started on the primary monitor or any monitor with the same scaling as the primary monitor but the scaling is completely wrong if any Form (the main Form of the app or a secondary top level Form) is first shown on a display with different DPI than the primary monitor. For example, if the app is started on a 4k/250% scaling laptop screen (with four other monitors at 1920x1080/100% scaling) then the Form gets displayed at 1:1 scaling on the 4k screen and shows up as a tiny 1 square inch on that screen (with only the Title and MenuBar correctly scaled): Image Showing Bad Scaling.
The issue appears to be caused by the fact that the CurrentAutoScaleDimensions of the Form are not being set correctly in these cases. They appear to be set to the current "dimensions" of the primary screen and not the screen that the Form is being shown on. However, if the Form is first shown on the primary screen and then moved to a screen with different DPI, the CurrentAutoScaleDimensions do get correctly updated to reflect the actual DPI of the destination screen and the Form gets scaled correctly. So, for example, if I set the primary screen to be the 4k/250% screen and then start the app on a 1920x1080/100% screen, the CurrentAutoScaleDimensions (incorrectly) get set to those for the 4k/250% screen and result in the Form being extremely overscaled. But if I start the app on the primary 4k/250% screen, it gets scaled correctly when first shown and then also scales correctly as it is dragged to other monitors (and back). In summary, when a Form is first shown, the CurrentAutoScaleDimensions seem to be always getting set to the primary monitor dimensions and not the dimensions of the screen that the Form is being shown on.
Does anyone know of remedy for this situation?
The best solution I have been able to come up with is to force the application to always start up on the Primary Screen regardless of what screen it was launched from. This seems to fix all issues with initial scaling of the main Form and all subsequent scaling as it is dragged between monitors seems fine:
public Form1()
{
this.Font = SystemFonts.IconTitleFont;
// Force the main Form of the app to always open on the primary screen
// to get scaling to work.
this.Location = Screen.PrimaryScreen.WorkingArea.Location;
this.StartPosition = FormStartPosition.Manual;
InitializeComponent();
...
For secondary Forms generated by the application, I have found that they get scaled correctly if I first show them on the primary screen, then hide and redisplay them on the screen containing the application's main Form (where I want them to be displayed). In some cases, I found it was sufficient to just call f.PerformLayout() rather than actually showing the form on the primary screen, but that did not work in all cases.
private void secondFormToolStripMenuItem_Click(object sender, EventArgs e)
{
FormExtra f = new FormExtra(this);
// First display the Form on the primary screen to make scaling correct
f.StartPosition = FormStartPosition.Manual;
f.Location = Screen.PrimaryScreen.WorkingArea.Location;
f.Show();
// Then hide it and move it where we really want it
f.Hide();
f.StartPosition = FormStartPosition.CenterParent;
f.ShowDialog();
}
This solution is not ideal in that the form briefly flashes on another screen which seems rather kludgy. However, this solution does seem to result in correct scaling of all Forms in the application regardless of what monitor the app is started on. I have tested it on two different multi-monitor configurations so far.
I want to draw directly on the desktop in C#. From searching a bit, I ended up using a Graphics object from the Desktop HDC (null). Then, I painted normally using this Graphics object.
The problem is that my shapes get lost when any part of the screen is redrawn. I tried a While loop, but it actually ends up drawing as fast as the application can, which is not the update rate of the desktop.
Normally, I would need to put my drawing code in a "OnPaint" event, but such thing does not exist for the desktop.
How would I do it?
Example code: https://stackoverflow.com/questions/1536141/how-to-draw-directly-on-the-windows-desktop-c
I posted two solutions for a similar requirement here
Basically you have two options.
1- Get a graphics object for the desktop and start drawing to it. The problem is if you need to start clearing what you have previously drawn etc.
Point pt = Cursor.Position; // Get the mouse cursor in screen coordinates
using (Graphics g = Graphics.FromHwnd(IntPtr.Zero))
{
g.DrawEllipse(Pens.Black, pt.X - 10, pt.Y - 10, 20, 20);
}
2- The second option that I provide in the link above is to create a transparent top-most window and do all your drawing in that window. This basically provides a transparent overlay for the desktop which you can draw on. One possible downside to this, as I mention in the original answer, is that other windows which are also top-most and are created after your app starts will obscure your top most window. This can be solved if it is a problem though.
For option 2, making the form transparent is as simple as using a transparency key, this allows mouse clicks etc. to fall through to the underlying desktop.
BackColor = Color.LightGreen;
TransparencyKey = Color.LightGreen;
When you draw to HDC(NULL) you draw to the screen, in an unmanaged way. As you've discovered, as soon as windows refreshes that part of the screen, your changes are overwritten.
There are a couple of options, depending upon what you want to achieve:
create a borderless, possibly
non-rectangular window. (Use
SetWindowRgn to make a window
non-rectangular.) You can make this a child of the desktop window.
subclass the desktop window. This is not straightforward, and involves
injecting a DLL into the
Explorer.exe process.
To get an OnPaint for the desktop you would need to subclass the desktop window and use your drawing logic when it receives a WM_PAINT/WM_ERASEBKGND message.
As the thread you linked to says, you can only intercept messages sent to a window of an external process using a hook (SetWindowsHookEx from a DLL).
As mentioned a transparent window is another way to do it, or (depending on the update frequency) copying, drawing and setting a temporary wallpaper (as bginfo does).
This is difficult to do correctly.
It will be far easier, and more reliable, to make your own borderless form instead.
i was just wondering what i need to research to be able to have a programme that is in the system tray, when the user clicks the programme icon, just above the system tray a small text area appears allowing the user to type in a search condition. There is plenty of resources for c# and getting your programme in the system tray, but then it just opens as normal, which is not quite what i am looking for.
Thanks
One way to accomplish this is to use a standard WinForms window which contains a single text box and has no border. This window can then be displayed and positioned as normal (likely using many of the existing samples) but will appear as a floating text box.
var form = new MyTextBoxForm();
form.FormBorderStyle = BorderStyle.None;
form.StartPosition = FormStartPosition.Manual;
// position the form
form.ShowDialog();
Handle the NotifyIcon.Click event and show your form in the desired location.
For example:
var screen = Screen.PrimaryScreen;
form.Left = screen.WorkingArea.Right - form.Width;
form.Top = screen.WorkingArea.Bottom - form.Height;
Maybe with this Make your program in the system + add a menu you could try editing the menu, like you'd do a regular menu with toolstrips.... and change the label by a textbox.
Just a random idea.
I have a C# Windows application that I want to ensure will show up on a second monitor if the user moves it to one. I need to save the main form's size, location and window state - which I've already handled - but I also need to know which screen it was on when the user closed the application.
I'm using the Screen class to determine the size of the current screen but I can't find anything on how to determine which screen the application was running on.
Edit: Thanks for the responses, everyone! I wanted to determine which monitor the window was on so I could do proper bounds checking in case the user accidentally put the window outside the viewing area or changed the screen size such that the form wouldn't be completely visible anymore.
You can get an array of Screens that you have using this code.
Screen[] screens = Screen.AllScreens;
You can also figure out which screen you are on, by running this code (this is the windows form you are on)
Screen screen = Screen.FromControl(this); //this is the Form class
in short check out the Screen class and static helper methods, they might help you.
MSDN Link, doesn't have much..I suggest messing around in the code by yourself.
If you remember the window's location and size, that will be enough. When you set the position to the previously used position, if it happened to be on the second monitor it will go back there.
For example, if you have 2 monitors, both sized 1280x1024 and you set your window's left position to be 2000px, it will appear on the second monitor (assuming the second monitor is to the right of the first.) :)
If you are worried about the second monitor not being there when the application is started the next time, you can use this method to determine if your window intersects any of the screens:
private bool isWindowVisible(Rectangle rect)
{
foreach (Screen screen in Screen.AllScreens)
{
if (screen.Bounds.IntersectsWith(rect))
return true;
}
return false;
}
Just pass in your window's desired location and it will tell you if it will be visible on one of the screens. Enjoy!
You can get the current Screen with
var s = Screen.FromControl(this);
where this is the Form (or any control on the Form). As about how to remember that is a little tricky, but I would go for the index in the Screen.AllScreens array, or maybe s.DeviceName. In either case, check before using the settings on startup, to prevent using a monitor that was disconnected.
The location of the form will tell you which screen the form is on. I don't really understand why you'd need to know what screen it is on, because if you restore it using the location you saved it should just restore to the same location (maybe you can expand as to why).
Otherwise you can do something like this:
Screen[] scr = Screen.AllScreens;
scr[i].Bounds.IntersectsWith(form.Bounds);
Each screen has a Bounds property which returns a Rectangle. You can use the IntersectsWith() function to determine if the form is within the screen.
Also, they basically provide a function that does this as well on the Screen class
Screen screen = Screen.FromControl(form);
You can use the 'Screen' object:
System.Windows.Forms.Screen
Start playing with something like this:
Screen[] screens = Screen.AllScreens;
for (int i = 0; i < screens.Length ; i++)
{
Debug.Print(screens[i].Bounds.ToString());
Debug.Print(screens[i].DeviceName);
Debug.Print(screens[i].WorkingArea.ToString());
}
It may get you what you need
So I have two forms, mainform and extraform.
extraform is set always moved to the right of mainform when mainform initializes
Sometimes mainform takes up both monitors and extraform is pushed off the screen never to be seen again. I would like to prevent this if possible. How can I do so? It must support dual monitors, that may or may not have distance between them (i.e. screen 1 is 20px to the left of screen 2).
How can I do this?
You can use the Screen class to work out where your window is relative to the desktop. The Screen class has a FromRectangle method, so you can figure out which screen you should be positioning your Form on (by passing your form's Bounds property in).
Each Screen object has a Bounds property, which you can use to compare to the location and size of your window, and adjust them accordingly.
It depends what you want should happen when extraform is pushed beyond the bounds of the screen(s).
However, to find out whether or not it's being pushed off, it's quite simple using the System.Windows.Forms.Screens class. Then you can do bounds checking like so:
foreach (var screen in Screen.AllScreens)
{
if(screen.Bounds.Contains(this.Bounds))
{
Console.WriteLine("Device "+screen.DeviceName+" contains form!");
}
}
Code assumes being in a form. Note that this code only prints that a screen contains the form if the form is completely contained on the screen. But this should be rather simple to fix, depending on your needs.
Perhaps the DesktopLocation property in your Forms can give you a clue about what's happening with what's happening with them