matlab appdesigner中按钮控件选择文件在坐标区中画图，并在下拉框选择方法在第二个坐标区画图

以下是一个使用MATLAB App Designer的示例代码，其中包含一个按钮控件和一个下拉框控件。当单击按钮时，它将打开一个文件选择对话框，用户可以选择一个数据文件。然后，根据下拉框中选择的方法，在第一个坐标区中绘制数据的图形，在第二个坐标区中绘制方法的图形。

classdef MyApp < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure            matlab.ui.Figure
        SelectFileButton    matlab.ui.control.Button
        MethodDropDown      matlab.ui.control.DropDown
        Axes1               matlab.ui.control.UIAxes
        Axes2               matlab.ui.control.UIAxes
    end

    % Properties that correspond to app data
    properties (Access = public)
        Data                % data from selected file
    end

    % Callbacks that handle component events
    methods (Access = private)

        % Button pushed function: SelectFileButton
        function SelectFileButtonPushed(app, event)
            % open file dialog and select data file
            [filename, pathname] = uigetfile({'*.txt';'*.csv'}, 'Select Data File');
            if isequal(filename,0) || isequal(pathname,0)
                % user cancelled file selection
                return;
            end
            % read data from file
            data = dlmread(fullfile(pathname, filename));
            app.Data = data;
            % plot data in Axes1
            plot(app.Axes1, data(:,1), data(:,2));
        end

        % Value changed function: MethodDropDown
        function MethodDropDownValueChanged(app, event)
            % get selected method
            method = app.MethodDropDown.Value;
            % plot method in Axes2
            switch method
                case 'Method 1'
                    plot(app.Axes2, app.Data(:,1), app.Data(:,2).^2);
                case 'Method 2'
                    plot(app.Axes2, app.Data(:,1), app.Data(:,2).^3);
                otherwise
                    error('Unknown method selected');
            end
        end
    end

    % App initialization and construction
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)

            % Create UIFigure
            app.UIFigure = uifigure;
            app.UIFigure.Position = [100 100 640 480];
            app.UIFigure.Name = 'My App';

            % Create SelectFileButton
            app.SelectFileButton = uibutton(app.UIFigure, 'push');
            app.SelectFileButton.ButtonPushedFcn = createCallbackFcn(app, @SelectFileButtonPushed, true);
            app.SelectFileButton.Position = [30 440 100 22];
            app.SelectFileButton.Text = 'Select File';

            % Create MethodDropDown
            app.MethodDropDown = uidropdown(app.UIFigure);
            app.MethodDropDown.Items = {'Method 1', 'Method 2'};
            app.MethodDropDown.ValueChangedFcn = createCallbackFcn(app, @MethodDropDownValueChanged, true);
            app.MethodDropDown.Position = [170 440 100 22];
            app.MethodDropDown.Value = 'Method 1';

            % Create Axes1
            app.Axes1 = uiaxes(app.UIFigure);
            title(app.Axes1, 'Data');
            xlabel(app.Axes1, 'X');
            ylabel(app.Axes1, 'Y');
            app.Axes1.Position = [30 60 250 350];

            % Create Axes2
            app.Axes2 = uiaxes(app.UIFigure);
            title(app.Axes2, 'Method');
            xlabel(app.Axes2, 'X');
            ylabel(app.Axes2, 'Y');
            app.Axes2.Position = [330 60 250 350];
        end
    end

    % App creation and deletion
    methods (Access = public)

        % Construct app
        function app = MyApp

            % Create UIFigure and components
            createComponents(app)

            % Initialize data
            app.Data = [];

            % Show the figure after all components are created
            app.UIFigure.Visible = 'on';
        end
    end
end