Question

我想创建一个按钮作为开/关开关：如果用户按下它，它会开始计数并在静态文本上显示计数器。如果用户再次按下它，它将停止计数。然后，如果用户第三次按下它，它将继续计数。

我试过这段代码

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

% Hint: get(hObject,'Value') returns toggle state of startStop_togglebutton

persistent counter ;

if isempty(counter)

    counter = 0 ;

end

button_state = get(hObject,'Value');

if button_state == get(hObject,'Max')

    set(handles.startStop_togglebutton,'String','Stop','ForegroundColor','red')

    setappdata(handles.startStop_togglebutton,'sw',1)

    while counter < 10

        counter = counter+1;

        set(handles.statusBar,'String',strcat(['the counter = ' num2str(counter) ]))

        pause(1)
    end

    set(handles.startStop_togglebutton,'String','Finished','ForegroundColor','cyan')
elseif button_state == get(hobject,'min')

    set(handles.startstop_togglebutton,'string','resume','foregroundcolor','blue')

    setappdata(handles.startstop_togglebutton,'sw',0)
    set(handles.statusBar,'String',strcat([' stopped & the counter = ' num2str(counter) ' !']))

end

但是它没有正常工作：当我第一次按下按钮时，它开始计数，当我按下它一秒钟时，它的名字改变了，但它还在计算中

Answer 1

在您当前的计数器实施中，while回调中的startStop_togglebutton循环会在您第一次按下按钮进行Start计数时激活。

即使您再次按下ushbutton到Stop计数，它仍会一直运行，直到条件（计数器<10）成立。

因此，要解决此问题，您可以使用“value”的startStop_togglebutton 1来增加计数器。

下面，您可以找到回调的更新版本。我还添加了几个“if”块来管理statusbar

中字符串的显示

% --- Executes on button press in startStop_togglebutton.
function startStop_togglebutton_Callback(hObject, eventdata, handles)
% hObject    handle to startStop_togglebutton (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of startStop_togglebutton

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

% Hint: get(hObject,'Value') returns toggle state of startStop_togglebutton

persistent counter ;

if isempty(counter)

    counter = 0 ;

end

button_state = get(hObject,'Value');

if button_state == get(hObject,'Max')

    set(handles.startStop_togglebutton,'String','Stop','ForegroundColor','red')

    setappdata(handles.startStop_togglebutton,'sw',1)

    while counter < 10
%
% Inserted acquisition of button state within the while loop
%
       button_state = get(hObject,'Value');
%
% Modified the counter increment:
%    the increment is based on the status of the button
%
%        counter = counter+1;
       counter = counter+button_state;
%
% Added "if" condition
%    The "statusbar" is updated only if counting is on
%
       if(button_state)
           set(handles.statusBar,'String',strcat(['the counter = ' num2str(counter) ]))
       end

       pause(1)
    end

%
% Added "if" condition
%    The "statusbar" is updatred only if counting is finished
%
if(counter == 10)
    set(handles.startStop_togglebutton,'String','Finished','ForegroundColor','cyan')
end

elseif button_state == get(hObject,'min')

    set(handles.startStop_togglebutton,'string','resume','foregroundcolor','blue')

    setappdata(handles.startStop_togglebutton,'sw',0)
    set(handles.statusBar,'String',strcat([' stopped & the counter = ' num2str(counter) ' !']))

end

更新回复评论

使用value的{{1}}递增计数器的原因如下：

第一次按togglebutton启动计数器时，togglebutton循环被激活，GUI正在“等待”另一个回调，无论循环是否完成。

此外，while循环已编码到捕捉开始/继续操作的while块中。

这意味着当你按下togglebutton来停止计数器时，会跳过while循环。

在while循环中获取togglebutton的值可以独立于预期的操作（停止/重新启动）捕获按钮状态的变化。

实际上，当您将其推送到停止计数器时，if设置为value，因此当您将其推送以重新启动时，它不会递增计数器，其值将设置为{{ 1}}并且计数器递增。

我建议以不同的方式对计数器GUI进行建模：

在单独的“.m”文件（或函数中）中对计数器进行编码
在此“.m”文件中编码计数器增量的逻辑（基于togglebutton的0）
添加运行计数器的按钮（“.m”文件）
仅使用1 callbach更新togglebutton上显示的value

使用startStop_togglebutton函数处理GUI和“.m”文件之间的数据。

“。m”。文件通过string识别GUI（在我用于测试解决方案的代码中，我将GUI图guidata设置为tag）。

您还应该将GUI的属性tag设置为“on”

以下您可以找到：

更新后的startStop_togglebutton回调，现在非常简单
用于启动计数器的按钮的回调
“.m”文件chich管理计数器

startStop_togglebutton回调

counter_gui

run_counter回调

HandleVisibility

“。m”管理计数器的文件

% --- Executes on button press in startStop_togglebutton.
function startStop_togglebutton_Callback(hObject, eventdata, handles)
% hObject    handle to startStop_togglebutton (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of startStop_togglebutton

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

% Hint: get(hObject,'Value') returns toggle state of startStop_togglebutton

button_state = get(hObject,'Value');

if(button_state == 1)
   set(handles.startStop_togglebutton,'String','Stop','ForegroundColor','red')
else
    set(handles.startStop_togglebutton,'string','resume','foregroundcolor','blue')
end

希望这有帮助。

Gui Matlab中的切换按钮

1 个答案: