Question

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上图是我的最终输出，open按钮用于查看各轴上显示的图像。我用以下代码来显示

function open1_Callback(filename, hObject, eventdata, handles)
% hObject    handle to open1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
fid=fopen(filename);
ax = handles.(sprintf('axes%d', 6));
imshow(ax)

其中，6是轴编号。但我得到的错误就像 undefined variable handles 要在轴上显示图像，我使用了以下代码

function displayResults(filename,hObject, eventdata, handles)

% Open 'filename' file... for reading...
fid = fopen(filename);
for N=6:1:10
    imagename = fgetl(fid);
    if ~ischar(imagename), break, end       % Meaning: End of File...
    [x,map]=imread(imagename);
    rgb=ind2rgb(x,map);
    ax = handles.(sprintf('axes%d', N));
    image(rgb, 'Parent', ax);
    set(ax, 'Visible','off');
    %xlabel(imagename);  
end
guidata(hObject,handles)

filename是一个文本文件。如何使用PUSHBUTTON显示相应的图像？

Answer 1

这是因为你弄乱了GUIDE生成的代码。通常回调函数定义如下所示：

function SomeButton_Callback(hObject, eventdata, handles)

但是在你的代码中你写了

function open1_Callback(filename, hObject, eventdata, handles)

但是指南仍然按照特定的顺序向回调函数（hObject，eventdata和handles）发送三个参数。所以MatLab感到困惑并抛出错误。

您最好将文件名放入handles函数中的*_OpeningFcn结构中，然后在所有回调中使用它。

在*_OpeningFcn结束时，您应添加以下内容：

% Here you may put all the data you need in your GUI
% just be sure to keep all the fields in handles structure from overwriting
% Safe way is to add MyData field and add all the stuff to it
handles.MyData.ListFileName = 'FileName.txt';
% the next two lienes are generated by GUIDE

% Update handles structure
guidata(hObject, handles);

然后在按钮的回调功能

function open1_Callback(hObject, eventdata, handles)
% hObject    handle to open1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% open the file
fid=fopen(handles.MyData.ListFileName);
% load lines from the file
% and do what is needed
for N=6:1:10
    imagename = fgetl(fid);
    if ~ischar(imagename), break, end       % Meaning: End of File...
    [x,map]=imread(imagename);
    rgb=ind2rgb(x,map);
    ax = handles.(sprintf('axes%d', N));
    image(rgb, 'Parent', ax);
    set(ax, 'Visible','off');
    %xlabel(imagename);  
end
% dont' forget to close the file
fclose(fid);
% If your callback function modifies data in handles.MyData structure
% you MUST update it back otherwise subsequent call-backs will not see it
guidata(hObject, handles);

是的，您使用fopen功能打开的所有文件都应使用fclose关闭。当你无法在你最喜欢的编辑器中更新文件时，你会学到很多东西，因为其他程序正在使用它。

另见（Making universal variables in MATLAB GUI）

更新以反映评论中的讨论：

要实现您想要的行为，我会执行以下操作：

在*_OpeningFcn结束时添加以下内容：

% Here you may put all the data you need in your GUI
% just be sure to keep all the fields in handles structure from overwriting
% Safe way is to add MyData field and add all the stuff to it
handles.MyData.ListFileName = 'FileName.txt';
handles.MyData.FileNames = {}; % here we store all the image names
handles.MyData.Images    = {}; % here we store all images
% Now we parse data from the file
fid=fopen(handles.MyData.ListFileName);
for N=6:1:10
    imagename = fgetl(fid);
    if ~ischar(imagename), break, end       % Meaning: End of File...
    [x,map]=imread(imagename);
    rgb=ind2rgb(x,map);
    ax = handles.(sprintf('axes%d', N));
    image(rgb, 'Parent', ax);
    set(ax, 'Visible','off');
    %xlabel(imagename);

    % store file name and image itself for later use
    handles.MyData.Images{N} = rgb;
    handles.MyData.FileNames{N} = imagename;

    % we have buttons like open1 open2 open3 etc...
    % add some info to the open buttons
    % so they will be aware which image they display
    btn = handles.(sprintf('open%d', N));
    set(btn, 'UserData',N);
end
% dont' forget to close the file
fclose(fid);
% the next two lienes are generated by GUIDE

% Update handles structure
guidata(hObject, handles);

然后在打开按钮的回调功能中执行以下操作

function open1_Callback(hObject, eventdata, handles)
% hObject    handle to open1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

N   = get(hObject,'UserData');
rgb = handles.MyData.Images{N};
ax  = handles.(sprintf('axes%d', N));
% create figure in 'modal' mode, so user have to close it to continue
figure('WindowStyle','modal', 'Name',handles.MyData.FileNames{N} );
% show image
image(rgb, 'Parent', ax);
set(ax, 'Visible','off');
% If your callback function modifies data in handles.MyData structure
% you MUST update it back otherwise subsequent call-backs will not see it
guidata(hObject, handles);

基本上，这个回调是通用的：它应该可以在不修改所有打开按钮的情况下工作。您甚至可以将GUIDE中的open2，open3 ...按钮的回调功能更改为open1_Callback。

查看轴上显示的图像

1 个答案: