如何从GUIDE GUI返回自定义值而非图形句柄？

Alright, let's figure out how to make your GUIDE-based MATLAB GUI return a custom value instead of the default figure handle when you call it like value = myGui();. I've got a couple of solid methods for you, depending on how complex your GUI is:

This is the most robust approach since it leverages GUIDE's native functionality to handle output values. Here's how to set it up:

• Step 1: Modify the OpeningFcn to pause execution
  In your GUI's OpeningFcn, set the window to modal (optional but highly recommended to prevent users from interacting with other windows before finishing with your GUI) and use waitfor to hold the function until the window is closed:

  function myGui_OpeningFcn(hObject, eventdata, handles, varargin)
      % Optional: Make the GUI modal to force focus
      set(hObject, 'WindowStyle', 'modal');
      % Initialize the custom output value (default to empty if needed)
      handles.output = [];
      guidata(hObject, handles);
      % Wait until the GUI window is destroyed (either by user close or your code)
      waitfor(hObject);
  

• Step 2: Update the output value in your action callback
  When the user completes their task (e.g., clicking an "OK" button), capture the custom value you want to return, save it to the handles structure, then close the GUI:

  function pushbutton_ok_Callback(hObject, eventdata, handles)
      % Example: Get input from an edit box and convert to a number
      user_input_str = get(handles.edit1, 'String');
      custom_value = str2double(user_input_str);
      
      % Save the custom value to the handles structure
      handles.output = custom_value;
      guidata(hObject, handles);
      
      % Close the GUI to trigger the OutputFcn
      delete(handles.figure1);
  

• Step 3: Configure the OutputFcn to return your value
  Modify the auto-generated OutputFcn to return the custom value stored in handles instead of the default figure handle:

  function varargout = myGui_OutputFcn(hObject, eventdata, handles)
      % Pass your custom value as the output
      varargout{1} = handles.output;
      % If you need multiple outputs, add more lines like:
      % varargout{2} = handles.another_value;
  

Now when you call value = myGui();, the GUI will open, wait for the user to click OK (or close it), then return your custom value instead of the figure handle.

If your GUI is straightforward and you don't want to mess with the OutputFcn, you can use setappdata and waitfor to track the custom value directly in the main GUI function:

function custom_value = myGui()
    % GUIDE's auto-generated setup code (keep this as-is)
    gui_Singleton = 1;
    gui_State = struct('gui_Name',       mfilename, ...
                       'gui_Singleton',  gui_Singleton, ...
                       'gui_OpeningFcn', @myGui_OpeningFcn, ...
                       'gui_OutputFcn',  @myGui_OutputFcn, ...
                       'gui_LayoutFcn',  [] , ...
                       'gui_Callback',   []);
    if nargin && ischar(varargin{1})
        gui_State.gui_Callback = str2func(varargin{1});
    end
    
    % Run the GUI setup
    gui_mainfcn(gui_State, varargin{:});
    
    % Wait until we set a "done" flag in the window's UserData
    waitfor(gcf, 'UserData');
    % Retrieve the custom value we stored
    custom_value = getappdata(gcf, 'custom_value');
    % Clean up the window
    delete(gcf);
end

Then in your OK button callback:

function pushbutton_ok_Callback(hObject, eventdata, handles)
    % Capture your custom value
    custom_value = str2double(get(handles.edit1, 'String'));
    % Store it in the window's app data
    setappdata(handles.figure1, 'custom_value', custom_value);
    % Set the "done" flag to trigger the waitfor in the main function
    set(handles.figure1, 'UserData', 'completed');
end

• Modal Windows: Setting WindowStyle='modal' ensures the user can't interact with other MATLAB windows until they finish with your GUI, which prevents accidental early returns of the default figure handle.
• Multiple Outputs: For Method 1, just add more entries to varargout in the OutputFcn and call the GUI with [val1, val2] = myGui();.
• Avoid Early Returns: Make sure you only close the GUI or trigger the waitfor condition after the custom value is fully ready—otherwise, you'll get the default figure handle instead of your desired value.

内容的提问来源于stack exchange，提问作者wgrant