如何在另一个函数中调用一个函数中使用的变量？

Question

我已经创建了一个matlab gui，我想使用函数（pushbutton2）中的函数（pushbutton1）变量magE 。

我怎么称呼它？

magE = matrix of 244 rows and 2000 Columns

我将不胜感激。 谢谢！

Answer 1

一种方法是在主脚本中将magE声明为全局变量。 然后，在每个函数内部，还应将其声明为全局变量，以便它引用相同的全局变量。

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

您应该使用hObject句柄在GUI函数和回调之间传递数据，这在自动生成的注释中已得到很好的解释。 取自MATLAB文档的示例：

% --- 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)

假设您需要访问按钮回调中的numberOfErrors字段。 您的回调代码现在看起来像这样：

% --- 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)