Set specific size to application's window programmatically

Question

My program (C#) is a taskbar and in its menu I can launch applications, compatible XP to 8.1. I would like to start any applications with a specific window's size, because few applications (OpenOffice, LibreOffice...), start flattened when i launch them for the first time.

I've tested to maximize this window with ShellExecute with ShowCommands.SW_MAXIMIZE parameter:

ShellExecute(IntPtr.Zero, "open", executablePath, executableParam, "", ShowCommands.SW_MAXIMIZE);

But when I clicked on the "restore" button of the window, there is the same problem, the window is flattened.

While the "restored" size isn't configured by manual resizing, the used value is specific for each applications.

Instead of ShellExecute, I use CreateProcess to specify a size :

const uint NORMAL_PRIORITY_CLASS = 0x0020;
STARTUPINFO si = new STARTUPINFO();
si.dwY = 50;
si.dwX = 50;
si.dwXSize = 200;
si.dwYSize = 800;
si.dwFlags = 0x00000006; //STARTF_USESIZE + STARTF_USEPOSITION
PROCESS_INFORMATION pi = new PROCESS_INFORMATION();

CreateProcess(programPath, programParams, IntPtr.Zero, IntPtr.Zero, true, NORMAL_PRIORITY_CLASS, IntPtr.Zero, null, ref si, out pi);

But there is one problem, we can launch an other OpenOffice/LibreOffice process with File->New->... In this case the application isn't launch by my program so my default size isn't applied.

I've checked the Windows Registry before and after changing this value, two keys are changed :

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\ComDlg32\OpenSavePidlMRU\reg]
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\UserAssist\{CEBFF5CD-ACE2-4F4F-9178-9926F41749EA}\Count]

These keys contains hexa values (first key) :

before :

"MRUListEx"=hex:00,00,00,00,04,00,00,00,01,00,00,00,05,00,00,00,03,00,00,00,02,\00,00,00,ff,ff,ff,ff

after :

"MRUListEx"=hex:01,00,00,00,00,00,00,00,04,00,00,00,05,00,00,00,03,00,00,00,02,\00,00,00,ff,ff,ff,ff

It isn't understandable to me, so I'm still searching if exist a programmatic way to specific window size of an application/all applications or an other specification to set into the Windows Registry. I'm not searching a solution to resize or move a window already launched like SetWindowPos.

But many websites explain there's just one solution to define the window's size: "drag the window to the size, then close the window and restart it"

http://help.wfu.edu/public/computers/standard-load-software/windows-7---set-default-window-size http://www.tomshardware.co.uk/forum/28659-45-change-default-window-size

This answer is the final solution or there is a way to do it programmatically?

Thanks in advance.

EDIT :

Actually, when a window is restored, I resize only the first time until the user kill it. My program keeps every window's handle in an object with a boolean initialized to false to specify if my window has been resized. I use GetForegroundWindow then with GetWindowPlacement I check if WINDOWPLACEMENT.flags == WindowPlacementFlag.WPF_NONE and if my boolean is always egals to false in that case I use GetWindowRect and SetWindowPos to set a specific size with the same position and assign my boolean to true.

I think is a good solution, but I loose the saved position by user (I can do it when window's size is under a specific value but the problem still there) and we seen the resizing...

Answer 1

This problem usually occurs because the coder used GetWindowPos to get the position to save, but the window is closed while minimised, so the position is a tiny window hidden by the taskbar. This is then the position which is saved. The correct method is to use GetWindowPlacement to save the position.

You could enumerate all top-level windows, check GetWindowPlacement to see which are visible and restored but with an inappropriate size or position (e.g. off-screen, too small). Then you could call SetWindowPlacement to move those windows back to a reasonable minimum size on-screen.

In all likelihood when they save their position again they will save the new position.

Don't poll though. Instead make it a utility that the user can run when they need to. (You will probably need an exceptions list too - some utilities might create an off-screen window on purpose.)