如何在另一個函數中調用一個函數中使用的變量？

Question

我已經創建了一個matlab gui，我想使用函數（pushbutton2）中的函數（pushbutton1）變量magE 。

我怎么稱呼它？

magE = matrix of 244 rows and 2000 Columns

我將不勝感激。 謝謝！

Answer 1

一種方法是在主腳本中將magE聲明為全局變量。 然后，在每個函數內部，還應將其聲明為全局變量，以便它引用相同的全局變量。

例如

global magE
<your_code_here>

function [] = pushbutton1()
  global magE
  %%<your_code_here>
end

function [] = pushbutton2()
  global magE
  %%<your_code_here>
end

Answer 2

您應該使用hObject句柄在GUI函數和回調之間傳遞數據，這在自動生成的注釋中已得到很好的解釋。 取自MATLAB文檔的示例：

% --- Executes just before simple_gui_tab is made visible.
function my_GUIDE_GUI_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 simple_gui_tab (see VARARGIN)
% ...
% add some additional data as a new field called numberOfErrors
handles.numberOfErrors = 0;
% Save the change you made to the structure guidata(hObject,handles)

假設您需要訪問按鈕回調中的numberOfErrors字段。 您的回調代碼現在看起來像這樣：

% --- Executes on button press in pushbutton1.
function my_GUIDE_GUI_pushbutton1_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% ...
% No need to call guidata to obtain a structure;
% it is provided by GUIDE via the handles argument
handles.numberOfErrors = handles.numberOfErrors + 1;
% save the changes to the structure
guidata(hObject,handles)