I'm currently creating a GUI using mathlab GUIDE. Since the GUI is very slow I'd like to add an edit_text uicontrol in order to show whether the GUI is running or not.
For instance I have a push_button that changes the plot in an axes. When the user click on this button the GUI takes several seconds to perform the new plot. What I want to do is setting the edit_text with the string 'running' as soon as the button was pressed. When the callback is done and the plot plotted I'd like to set the edit_text with another string : 'ready'.
I used the following code :
function push_button_Callback(hObject, eventdata, handles)
% hObject handle to push_button (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
set(handles.edit_text,'String','Running...');
%a bunch of code...
set(handles.edit_text,'String','Ready.');
guidata(hObject,handles);
I hoped that once the callback is called, the GUI would display 'running...' on my edit_text. Apparently I was wrong. When running the GUI and pressing the push_button the plot changes but the edit_text remains the same.
Then I tried something else using the ButtonDownFcn callback. My idea was that the latter callback would be executed before the actual callback (written above). Here is the code :
function push_button_ButtonDownFcn(hObject, eventdata, handles)
% hObject handle to push_button (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
set(handles.edit_text,'String','Running...');
guidata(hObject,handles);
The problem is that the ButtonDownFcn callback isn't executed every time. As GUIDE says about the latter callback :
% --- If Enable == 'on', executes on mouse press in 5 pixel border.
% --- Otherwise, executes on mouse press in 5 pixel border or over str22.
Obviously I want my push_button to be enabled, otherwise it won't work the way I want. So I don't know what else to try.
Has someone any idea how I could manage to do that ?
You could try doing
set(handles.edit_text,'String','Running...');
drawnow;
%a bunch of code...
The GUI might not be updated until you get to
set(handles.edit_text,'String','Ready.');
So forcing it to update with drawnow might work for you.
Related
using GUIDE I have now a programm whose output is a vector and a plot of its data. Because the plot has many little variations, I used the csaps function to get a smoothier plot. I want now to add a slider to my figure to change the smoothing parameter and I want that the plot to be updated each time the value of the slider changes. How can I do this? I found this on mathworks.com but I coudn't apply it to my case: https://de.mathworks.com/help/control/ref/stepplot.html .
Add callback to your slider. To do so in GUIDE press right mouse button on the slider and select view callbacks -> callback. It will create something like this in .m file of your GUIDE object:
function slider_Callback(hObject, eventdata, handles)
% hObject handle to slider (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% Hint: get(hObject,'Value') returns toggle state of slider
Everything you will place under %Hint would be executed every time the slider is changing its state. For example you can re-plot the graph:
% Hint: get(hObject,'Value') returns toggle state of slider
plot(x_value,y_value);
So I'm building a classifier of images. In the GUI a image loads and insert a value on a text box, and push a button. I'm having a problem loading the image in the axes. Because when the axes function is called the handles is zero(due to:% handles empty - handles not created until after all CreateFcns called). And my problem is, how do I get to just call one image at a time for the axes.
The ideal solution, is I create a handles.images=imagedatastore, and every time I push the button I add to a counter(which I already have made) and then that give the indices to get the image from the datastore. My problem with this is that I can't get the first picture, because in the beginning the handles are empty. I have made the callfunction for the axes:
% --- Executes during object creation, after setting all properties.
function axes1_CreateFcn(hObject, eventdata, handles)
% hObject handle to axes1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles empty - handles not created until after all CreateFcns called
[pict_croped,Nphotos,Date_img] =getcropedimagages;
handles.img =pict_croped;
i=readimage(handles.img,1);
% axes(hObject)
imshow(i)
% Hint: place code in OpeningFcn to populate axes1
but this has two problems, first, I don't really want to call the function that creates the datastore all the time I push the button, second, I still can't get the indice of the counter to be in the function,if I have:
i=readimage(handles.img,handles.counter)
it will give me the error in the first time, of not having handles.counter
Any idea how to solve this?This is the first GUI I'm building.
The issue is very clearly in the comment that GUIDE provides for you. The handles struct isn't populated until all CreateFcn have been run so you'll want to use the OpeningFcn to do any initialization of the graphics objects. You can then add any data you need to the handles struct and save it using guidata so that it's available from within all of your other callback functions.
function OpeningFcn(hObject, eventData, handles)
[pict_croped,Nphotos,Date_img] = getcropedimagages;
handles.img = pict_croped;
i = readimage(handles.img,1);
imshow(i, 'Parent', handles.haxes1)
% "Save" the changes to the handles object
guidata(hObject, handles)
Well, I end up with:
in the opening fucntion:
i = readimage(handles.img,handles.counter);
imshow(, 'Parent', handles.axes1)
and in the button call back:
i = readimage(handles.img,handles.counter);
imshow(i, 'Parent', handles.axes1)
inthe end is a very simple solution, I think I was just mind blocked over the first iteration...
i have a GUI based in matlab 2015 to code
when i push/ press the button one of edit box data keeps changing but i want its value to keep on changing according to my call back until i release it
for now i have to keep on clicking my push button again and again which changes my edit box value
Kindly suggest me a workarround
% --- Executes on button press in pushbutton27.
function pushbutton27_Callback(hObject, eventdata, handles)
% hObject handle to pushbutton27 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
Freq = (str2double(get(handles.edit4,'String')))+ 0.001;
if Freq > 20
set(handles.edit4,'String','20');
else
set(handles.edit4,'String',num2str(Freq));
end
uicontrol has only the Callback and ButtonDownFcn properties that respond to mouse clicks. If the property Enable of the uicontrol is set to 'on', only the function specified in Callback reacts to left-clicks. If the property is set to 'off' or 'inactive' it also reacts to right-clicks. Because for inactive uicontrols you cannot change the Value by clicking on it, I don't see a direct solution using uicontrol.
A solution is to use the figure's WindowButtonDownFcn and WindowButtonUpFcn properties. For the button down you could use something like:
function buttondown(hobj,~,hedit)
hobj.UserData = true;
while hobj.UserData
pause(0.2); % put a pause so it doesnt change too fast
hedit.String = datestr(now); % you can set it to anything you want here
end
end
For the button up:
function buttonup(hobj,~)
hObj.UserData = false;
end
Of course, if you have multiple buttons that have to work this way, in the buttondown function you must test where the cursor's position is that by checking the CurrentPoint property.
I'm working on a program and have decided to build a GUI around it. What I'd like to start with is pretty simple, load up a movie and be able to scroll through it. I've looked at a lot of the questions regarding listeners, and in fact someone asked this question but the solution there didn't seem to work for me.
in my opening function of the gui I have
handles.output = hObject;
handles.sliderListener = addlistener(handles.Image_Slider,'ContinuousValueChange', ...
#(hObject, event) Image_Slider_ContValueCallback(...
hObject, eventdata, handles));
% Update handles structure
guidata(hObject, handles);
And then I have the following two call backs :
function Image_Slider_Callback(hObject, eventdata, handles)
% hObject handle to Image_Slider (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
handles=guidata(hObject);
current_slice = round(get(handles.Image_Slider,'Value'));
%size(handles.Image_Sequence_Data(:,:,current_slice));
im =imagesc(handles.Image_Sequence_Data(:,:,current_slice),'Parent',handles.Image_Sequence_Plot);
colormap('gray');
which works fine (without the listener everything behaves properly)
AND then I also have
function Image_Slider_ContValueCallback(hObject, eventdata, handles)
% hObject handle to Image_Slider (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
handles=guidata(hObject);
current_slice = round(get(handles.Image_Slider,'Value'));
%size(handles.Image_Sequence_Data(:,:,current_slice));
handles=guidata(hObject);
%im =
imagesc(handles.Image_Sequence_Data(:,:,current_slice),'Parent',handles.Image_Sequence_Plot);
colormap('gray');
which I think should be called when the slider is moved continuously. My issue is that EACH time the slider value is changed a blank ("figure 1") appears. The actual GUI data responds correctly, but I don't understand why/where this 'rogue' figure is coming from..
someone please help. Also, any opinions on imshow vs. imagesc as to which is better (this GUI will involve a lot of user interaction with the image)
I had pretty much the same problem once! I don't have access to Matlab right now so I can't test a working example , but for the moment I would suggest to place this line:
handles.sliderListener = addlistener(handles.Image_Slider,'ContinuousValueChange', ...
#(hObject, event) Image_Slider_ContValueCallback(...
hObject, eventdata, handles));
in the CreateFcn of your slider. Maybe a blank figure appears each time you move the slider since it does not know that it's linked to a listener object and thus creates one continuously.
If it does not work, you can call a function outside of the GUI to update the current frame displayed in your axes, for instance:
handles.sliderListener = addlistener(handles.Image_Slider,'ContinuousValueChange', ...
#(a,b) UpdateCurrentFrame);
instead of the callback in your GUI. a and b are dummy input arguments and UpdateCurrentFrame can simply contain a call to imshow for example. It might not be the most elegant way but it worked perfectly for me.
Oh and as for your question about imagesc and imshow, I personnally prefer imshow. In my case, I used text annotations and rectangles for ROI selection and so on, and had little problems with imagesc in terms of images not updating correctly or rectangles being stuck...but it might be that I was not using it correctly though.
Hope that helps!
I am quite new to MATLAB GUI programming (using GUIDE sorry) and I have the following issue: The GUI displays on an axis an image sequence stored in a cell array. I have a couple of pushbuttons and a slider to scroll through the sequence. In order to get a 'continuous slider' I use a listener, which kind of works but creates some problems:
1) When I press the slider, a figure is created and the first frame of the sequence is displayed in it, but as I move the slider the sequence is displayed in the axis of my GUI (which is what I want) and the figure becomes empty. Can anybody tell me why this figure is created and how can I avoid it?
2) Once I press the slider button and thus use the listener, all handles inside the GUI are not functionnal as Matlab does not recognize them and I'm stuck with a functionnal slider/display but I can't use the pushbuttons.
Any ideas on why this happens? Here is the code I use in the Create Function of the slider:
function slider2_Frame_Video_Callback(hObject, eventdata, handles)
hListener = addlistener(hObject,'ContinuousValueChange',#(a,b) slider2_Frame_Video_Callback(hObject, eventdata, handles)); % a and b are dummy arguments
guidata(hObject,handles)
In the slider callback, the code looks like this (basically imshow in the current axis):
axes(hAxis)
imshow(Movie{frame},'parent',hAxis);
drawnow
% This does not work either as handles.edit_FrameNumber is not recognized by Matlab
set(handles.edit_FrameNumber, 'String', frame);
guidata(hObject,handles);
Any hints are welcome thanks!
I wonder if part of the problem is that a listener is being instantiated each time the user moves the slider since the listener code is within this callback AND that the callback being provided to the listener (seems like some kind of strange back-and-forth there). So every time the user releases the mouse button after a slide, a new listener is created. This may be causing some problems with the other buttons not being responsive.
Rather than instantiating the listener there, I would do this in the Opening_Fcn of your GUI:
% --- Executes just before frameSlider is made visible.
function frameSlider_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject handle to figure
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% varargin command line arguments to frameSlider (see VARARGIN)
% Choose default command line output for frameSlider
handles.output = hObject;
if ~isfield(handles,'hListener')
handles.hListener = ...
addlistener(handles.slider1,'ContinuousValueChange',#respondToContSlideCallback);
end
% Update handles structure
guidata(hObject, handles);
My GUI is named frameSlider; yours will be something else. The above creates one listener with a callback to a function that you will need to define in the same *.m file, respondToContSlideCallback.
A sample body for the callback that is to respond to the continuous slide is
% --- Executes on slider movement.
function respondToContSlideCallback(hObject, eventdata)
% hObject handle to slider1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% Hints: get(hObject,'Value') returns position of slider
% get(hObject,'Min') and get(hObject,'Max') to determine range of slider
% first we need the handles structure which we can get from hObject
handles = guidata(hObject);
% test to display the current value along the slider
disp(['at slider coordinate ' num2str(get(hObject,'Value'))]);
If you run this code, the Command Window will display continuously the slider coordinate as you move the slider from end to end.
Your above code has a Movies cell array. How is that being accessed by your callback? Is it a global variable or ..? Where does hist come from? If Movies is the result of some other function call, then it can be saved to handles too (in whichever location it gets loaded from file). I suppose you will also have to map the slider control coordinates to the number of frames that you have (though maybe you have already done this?).