为什么这个MATLAB类没有保留其属性? [英] Why isn't this MATLAB class holding on to its properties?

问题描述

在这里一定缺少一些非常简单的东西.我有一个MATLAB类，该类创建一个包含两个按钮的图形，每个按钮调用相同的函数，但是这些按钮的句柄未保留在该函数中，我也不知道为什么.

There must be something very simple that I'm missing here. I have a MATLAB class which creates a figure containing two push-buttons, each button calls the same function, but the handles for those buttons aren't retained within that function, and I don't know why.

这是课程，简化了...

Here's the class, simplified...

classdef Test

    properties
        Figure
        ButtonA
        ButtonB
    end

    methods    
        function app = Test()       
            app.Figure = figure();

            app.ButtonA = uicontrol('Style', 'pushbutton', ...
                'String', 'Button A', ...
                'Position', [10, 10, 100, 20], ...
                'Callback', @app.PressButton);
            app.ButtonB = uicontrol('Style', 'pushbutton', ...
                'String', 'Button B', ...
                'Position', [10, 120, 100, 20], ...
                'Callback', @app.PressButton);
        end

        function PressButton(app, Button, ~)
            Button
            app.ButtonA
            app.ButtonB
        end
    end
end

如果我叫它，它将打开图形，并显示按钮的手柄编号:

If I call it it opens the figure, and displays the handle numbers for the buttons:

>> T = Test
T = 
  Test with properties:

     Figure: 8
    ButtonA: 745.000122070313
    ButtonB: 103.002319335938
>> T.ButtonA
ans = 745.000122070313
>> T.ButtonB
ans = 103.002319335938

如果按下按钮A，该函数将返回两个空值，就像尚未设置属性一样:

If I press Button A, the function returns two empty values, as if the properties have not been set:

Button =
          745.000122070313
ans =
     []
ans =
     []

如果我按下按钮B，则该函数的确会返回按钮A的值，但会返回按钮B的空值:

If I press Button B, the function does return the value for button A, but an empty value for button B:

Button =
          103.002319335938
ans =
          745.000122070313
ans =
     []

非常感谢您提出任何建议.

I'd be very grateful for any suggestions.

推荐答案

您应该从handle继承您的类. 检查matlab的value类和handle类之间的区别这里.

You should subclass your class from handle. Check the difference between matlab's value-class and handle-class here.

为此，请更改代码的第一行:

To do so, change the first line in your code:

 classdef Test < handle

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