how to put an app designer window in the center of the screen?

hi, i've been designed an app in matlab, now the problem is that i want to put the app window in the center of the screen without setting position by myself. i want to write some codes so that everytime anyone open the app, the window is automatically always in the center. is it possible and how to realize?

thank you!

the window now:

what i expect:

without setting this by the app user:

[Ricardo Carvalho]

What solution did you find for this problem?, the answers contained in the other comments do not work

[dpb]

What, specifically did you try? I've seen no problem in using <movegui> to one of the preset positions when I've tried; as noted, however, all the apps I've built seem to work just fine with the idea espoused in the Answer I gave, let the very first use of the app open at the default location, then save and restore the position as the user left it the previous time when returns. Each user has their own set of usersettings if the app is shared, depending upon the user login name.

Show us an example trial app startup code that "doesn't work" and then define what that means, specifically.

Answer 1

[dpb]

While you can do this using the .ScreenSize and .MonitorPositions properties retrieved from groot, I'd say it's quite rude and very egotistical to make your app appear in the middle of your users' screens regardless of their preferences.

It would be much better to let it default originally(*) and then save the position on close in a usersettings data structure and reload in last position on subsequent opens. Each user gets/keeps his own screen space that way.

(*) Or, alternatively, add a user preferences item in the menu that lets user select a given general location -- 'NW', 'NE', etc., ... something like what legend has for options. Just don't be adamant that your app must own the middle of the screen.

[rumin diao]

oh it's a great idea to let users to choose and save user's preference. thank you!!!

[Image Analyst]

I wouldn't say it's "quite rude and very egotistical" to come up centered instead of where they happened to have last left the app on the screen. A lot of times users are rearranging various windows on the screen, and where they last moved it to is not necessarily where they would like to have it the next time they launch the app. In fact usually my apps have so much stuff, including an image or two that I want to enlarge as much as possible so that users can see details better, that I maximize my apps by setting the WindowState property to 'maximized'.

Anyway, @rumin diao if you want my code, then scroll down to see it.

[Adee]

I assume the need to set the initial location to somewhere specific comes from the fact that the initial location in appdesigner is hard-coded in pixel units (in createComponents), and depending on the window size, it may not be suitable for all users.

The programmer may have a huge display and set the initial coordinates accordingly. The code generated by appdesigner does not check for the display size when the app is executed (a feature to look forward to?), and if a user has a smaller display, the window may be partly or completely off the display. Moving such windows is possible, but quite painful, and many users don't know how. It would not be rude or egoistical to help these users.

The initial location can be changed in the window properties in appdesigner, but it seems that appdesigner does not enable changing the units to normalized. Another feature to look forward to?

Answer 2

[Adee]

The built-in function movegui can be used.

movegui(fig,'center')

Will move the figure fig to the center of the current display. Other locations are also possible - see "doc movegui".

It works with appdesigner figures too.

You can call this function in a startupfcn callback. For example, if your GUI figure is called main_UIFigure:

function startupFcn(app)

movegui(app.main_UIFigure, 'center');

end

Answer 3

[Image Analyst]

I have a function to center the GUI on the screen. See below.

% Centers the figure on the screen.
function CenterFigure(handles)
try
    % The figure Position property does not include the window borders, 
    % so this example uses a width of 5 pixels on the sides and bottom and 30 pixels on the top.
    % 	borderWidth = 5;
    % 	titleBarWidth = 30;
    % Ensure root units are pixels:
    g = groot;
    g.Units = 'pixels';
    % Get the screen size in pixels:
    screenSize = g.ScreenSize;
    screenWidth = screenSize(3);
    screenHeight = screenSize(4);
    
    % Get the size of the window.
    childrenFigure = g.Children;
    if numel(childrenFigure) > 1
        return;
    end
    childrenFigure.Units = 'pixels';
    initialFigurePosition = childrenFigure.Position;
    
    % Create an array that will center it.
    centeredX = (screenWidth - initialFigurePosition(3)) / 2;
    centeredY = (screenHeight - initialFigurePosition(4)) / 2;
    centeredPosition  = [centeredX,...
        centeredY,...
        initialFigurePosition(3),...
        initialFigurePosition(4)];
    
    % Send the centered coordinates to the figure to actually cause the figure to move.
    childrenFigure.Position = centeredPosition;
catch ME
    errorMessage = sprintf('Error in program %s, function %s(), at line %d.\n\nError Message:\n%s', ...
        mfilename, ME.stack(1).name, ME.stack(1).line, ME.message);
    uiwait(errordlg(errorMessage));
    return;
end
return; % from CenterFigure()