Can I rely on the Handles numeration?
2 次查看(过去 30 天)
显示 更早的评论
I have a complex GUI (built with GUIDE) and among others, there are 10 pushbuttons.
Their handles are defined by the GUI. I have noticed that the difference between 1 button handle to the other is 1.
Can I relay on that? I re-ran the GUI several times and the handle values change but the delta remains.
I want to set the buttons 'Value' field in a loop or something like that.
Something like that:
first_h = handles.Button1
for i=1:10
Value = get(first_h + i ,'Value)
end
0 个评论
采纳的回答
Jan
2013-2-26
编辑:Jan
2013-2-26
No, you definitely cannot rely on the value of handles.
For accesing the handles in a loop, simply store them in a vector:
ButtonList = [handles.StatusButton1, handles.StatusButton2, ...
handles.StatusButton3, handles.StatusButton4];
for iButton = 1:length(ButtonList)
set(ButtonList(iButton), 'Value', rand>0);
end
As usual you can see, that hiding an index in the name of a variable is not handy. It would be much smarter, if GUIDE stores the handles in a vector directly, but this is not implemented yet.
Of course meaningful tags could help also, but it would be slower:
for iButton = 1:10
tag = sprintf('Button%d', iButton);
handle = findobj(get(handles.figure, 'children'), 'flat', ...
'Style', 'PushButton', 'tag', tag);
set(handle, 'Value', rand>0);
end
0 个评论
更多回答(2 个)
Daniel Shub
2013-2-26
I wouldn't rely on the handle ids behaving in any sensible way unless you set them at the outset. There is no reason to have to rely on them either. You should either set the handles at the outset and save them in a reasonable place within the appdata or add meaningful tags that allow you to then find the buttons at a later time.
the cyclist
2013-2-26
No, I don't think you can rely on that. In particular, most object handles are actually floating point numbers, not integers, and you should use the full precision to access them. (See, for example, this page: http://www.mathworks.com/help/matlab/creating_plots/accessing-object-handles.html.)
0 个评论
另请参阅
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!