Output from Gui results in error "Attempt to reference field of non-structure array"

1 次查看（过去 30 天）
Douglas Anderson
Douglas Anderson 2014-4-30
评论： Geoff Hayes 2014-4-30
Hello,
I have written a very simple GUIDE Gui to return the value of a slider to the command line. I set up a default value, and have a "Done" button. If the uiwait{} is commented out, the default values are returned to the command line (when requested), and if I decomment the uiwait(), I get the error message.
Again, the GUIDE figure consists of the slider with a text value that documents where the slider is, and a DONE button. That's it.
I have tried all kinds of permutations of the code, and this behavior mystifies me. Any thoughts as to why this happens? Thanks!
Doug Anderson
The code follows:
function varargout = foobar1(varargin)
% FOOBAR1 MATLAB code for foobar1.fig
% FOOBAR1, by itself, creates a new FOOBAR1 or raises the existing
% singleton*.
%
% H = FOOBAR1 returns the handle to a new FOOBAR1 or the handle to
% the existing singleton*.
%
% FOOBAR1('CALLBACK',hObject,eventData,handles,...) calls the local
% function named CALLBACK in FOOBAR1.M with the given input arguments.
%
% FOOBAR1('Property','Value',...) creates a new FOOBAR1 or raises the
% existing singleton*. Starting from the left, property value pairs are
% applied to the GUI before foobar1_OpeningFcn gets called. An
% unrecognized property name or invalid value makes property application
% stop. All inputs are passed to foobar1_OpeningFcn via varargin.
%
% *See GUI Options on GUIDE's Tools menu. Choose "GUI allows only one
% instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES
% Edit the above text to modify the response to help foobar1
% Last Modified by GUIDE v2.5 30-Apr-2014 10:06:42
% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
'gui_Singleton', gui_Singleton, ...
'gui_OpeningFcn', @foobar1_OpeningFcn, ...
'gui_OutputFcn', @foobar1_OutputFcn, ...
'gui_LayoutFcn', [] , ...
'gui_Callback', []);
if nargin && ischar(varargin{1})
gui_State.gui_Callback = str2func(varargin{1});
end
if nargout
[varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT
% --- Executes just before foobar1 is made visible.
function foobar1_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 foobar1 (see VARARGIN)
%Set Slider Starting Values
max_slider = 100;
min_slider = 1;
default_slider = 50;
slider_step = 1 / (max_slider - min_slider);
jumper = 1;
set(handles.slider_value,'max',max_slider);
set(handles.slider_value,'min',min_slider);
set(handles.slider_value,'value',default_slider);
set(handles.slider_value,'sliderstep',[slider_step,jumper]);
set(handles.slider_text,'string',default_slider);
handles.exit = default_slider;
% Choose default command line output for foobar1
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
% UIWAIT makes foobar1 wait for user response (see UIRESUME)
%uiwait(handles.figure1);
% --- Outputs from this function are returned to the command line.
function varargout = foobar1_OutputFcn(hObject, eventdata, handles)
% varargout cell array for returning output args (see VARARGOUT);
% hObject handle to figure
% eventdata reserved - to b e defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% Get default command line output from handles structure
varargout{1} = handles.output;
varargout{2} = handles.exit;
%delete(handles.figure1);
% --- Executes on button press in done_button.
function done_button_Callback(hObject, eventdata, handles)
% hObject handle to done_button (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
uiresume(handles.figure1);
delete(handles.figure1);
% --- Executes on slider movement.
function slider_value_Callback(hObject, eventdata, handles)
% hObject handle to slider_value (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% Hints: get(hObject,'Value') returns position of slider
% get(hObject,'Min') and get(hObject,'Max') to determine range of slider
set(handles.slider_text,'string',round(get(handles.slider_value,'value')));
handles.exit = round(get(handles.slider_value,'value'));
guidata(hObject,handles);
% --- Executes during object creation, after setting all properties.
function slider_value_CreateFcn(hObject, eventdata, handles)
% hObject handle to slider_value (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles empty - handles not created until after all CreateFcns called
% Hint: slider controls usually have a light gray background.
if isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
set(hObject,'BackgroundColor',[.9 .9 .9]);
end
% --- Executes when user attempts to close figure1.
function figure1_CloseRequestFcn(hObject, eventdata, handles)
% hObject handle to figure1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% Hint: delete(hObject) closes the figure
% Check appdata flag to see if the main GUI is in a wait state
%{
if getappdata(handles.figure1,'waiting')
% The GUI is still in UIWAIT, so call UIRESUME and return
uiresume(hObject);
setappdata(handles.figure1,'waiting',0)
else
% The GUI is no longer waiting, so destroy it now.
delete(hObject);
end
%}
delete(hObject);
  9 个评论
显示 7更早的评论
Douglas Anderson
Douglas Anderson 2014-4-30
OH!!!!!!!!!!!!!!!!!!
I see where the problem in Doug Hull's Video is!!!!!!!
You need to add a guidata(hObject,handles) in the CloseRequestFcn, like follows:
if isequal(get(hObject,'waitstatus'),'waiting')
%if getappdata(handles.figure1,'waiting')
% The GUI is still in UIWAIT, so call UIRESUME and return
uiresume(hObject);
guidata(hObject,handles);
else
% The GUI is no longer waiting, so destroy it now.
delete(hObject);
end
That way you can actually use the handles.exit and not have to call the get() in the OutputFcn. That's actually what I wanted, since the real code (not the foobar) has a structure containing the info from a bunch of sliders, all of which will be put into a handles.exit structure.
Doug Hull uses the getappdata/setappdata, but I just wanted to use the handles structure.
But thanks again, you really helped!

请先登录，再进行评论。

请先登录，再回答此问题。

回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Migrate GUIDE Apps 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by