Unfortunately, this is a regression in R2019a.
The workaround is to temporarily place the tab group in a different cell, then call drawnow, then place it back to its real location.
Example (outside AppDesigner):
f = uifigure;
g = uigridlayout(f);
c = uibutton(g);
tg = uitabgroup(g);
% Workaround:
%
% set it temporarily in a different location
tg.Layout.Row = 2;
% call drawnow
drawnow;
% set it back to its real location
tg.Layout.Row = 1;
Example (in AppDesigner):
% 1. Drag a tab group in a cell, e.g. row 3, column 1
% 2. Create a startup function and place the workaround in it, e.g.
%
% set it temporarily in a different location
app.TabGroup.Layout.Row = 4;
% call drawnow
drawnow;
% set it back to its real location
app.TabGroup.Layout.Row = 3;
Note:
The temporarily location MUST be different from its actual location.
To make sure that is the case, you can set the temporary location to a cell 'outside' the grid, for example, if the grid is of size 5x5, set the temporary Row to 6.
Another way is to add 1 to the row (or column), then place it back.
Bug report:
Please see the corresponding bug report for the latest info on the releases / updates in which this will be fixed:
