matlab - 如何以比官方记录更多的方式自定义 App Designer 人物？

Question

UndocumentedMatlab最近发表的一篇文章提到App Designer图形实际上是使用Dojo Toolkit的网页。这意味着我们理论上可以直接操作 HTML DOM 来实现某些原本不可用的 UI 自定义。

下面是 App Designer 图形定义的示例，显示在.mApp Designer 生成的文件中（在 MATLAB R2016a 上）：

classdef domDemo < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure     matlab.ui.Figure          % UI Figure
        LabelListBox matlab.ui.control.Label   % List Box
        ListBox      matlab.ui.control.ListBox % Item 1, Item 2, Item 3, It...
    end

    methods (Access = private)

        % Code that executes after component creation
        function startupFcn(app)

        end
    end

    % App initialization and construction
    methods (Access = private)

        % Create UIFigure and components
        function createComponents(app)

            % Create UIFigure
            app.UIFigure = uifigure;
            app.UIFigure.Position = [100 100 260 147];
            app.UIFigure.Name = 'UI Figure';
            setAutoResize(app, app.UIFigure, true)

            % Create LabelListBox
            app.LabelListBox = uilabel(app.UIFigure);
            app.LabelListBox.HorizontalAlignment = 'right';
            app.LabelListBox.Position = [50 93 44 15];
            app.LabelListBox.Text = 'List Box';

            % Create ListBox
            app.ListBox = uilistbox(app.UIFigure);
            app.ListBox.Position = [109 36 100 74];

        end
    end

    methods (Access = public)

        % Construct app
        function app = domDemo()

            % Create and configure components
            createComponents(app)

            % Register the app with App Designer
            registerApp(app, app.UIFigure)

            % Execute the startup function
            runStartupFcn(app, @startupFcn)

            if nargout == 0
                clear app
            end
        end

        % Code that executes before app deletion
        function delete(app)

            % Delete UIFigure when app is deleted
            delete(app.UIFigure)
        end
    end
end

...看起来像这样：

根据uilistbox（将我们重定向到完整属性列表的复选框属性页面）的文档，没有办法操纵例如列表项的文本对齐方式。如果是这样的话，

问题：我们如何操作ListBox示例应用程序中的 ，使其内容居中对齐，即使这样的设置对我们不可用？

Answer 1

为了成功完成这项任务，我们需要几件事：

• 查找 HTML/CSS 所在的位置（以便我们可以操作它们）。
• 找到我们要编辑的 DOM 元素。
• 找出我们需要做出的改变。
• 找到一种使用 MATLAB 操作元素的方法。

---

工作步骤：

1. 查找图形的 HTML/CSS 存储/定位的位置

win = struct(struct(struct(app).UIFigure).Controller).Container.CEF;
URL = win.URL; % Needed only for testing in browser

2.找到我们需要编辑的DOM的哪个元素

data_tag = char(struct(app.ListBox).Controller.ProxyView.PeerNode.getId);

使用浏览器验证：

3. 找出我们需要做出的改变

由于我们想要操作文本对齐，我们谷歌一些相关的关键字并找到CSStext-align属性。然后我们手动试试看是否真的有效：

4. 找到一种使用 MATLAB 操作元素的方法

使用dojo.style和dojo.query：

win.executeJS(['dojo.style(dojo.query("[data-tag^=''' data_tag ''']")[0],"textAlign","center")']);

---

此答案的完整代码：

classdef domDemo < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure     matlab.ui.Figure          % UI Figure
        LabelListBox matlab.ui.control.Label   % List Box
        ListBox      matlab.ui.control.ListBox % Item 1, Item 2, Item 3, It...
    end

    methods (Access = private)

        % Code that executes after component creation
        function startupFcn(app)
          % Customizations (aka "MAGIC GOES HERE"):
          drawnow; rez = [];
          warning off MATLAB:HandleGraphics:ObsoletedProperty:JavaFrame
          warning off MATLAB:structOnObject            
          while ~strcmp(rez,'"center"')
            try                
              % 1. Get a handle to the webwindow:
              win = struct(struct(struct(app).UIFigure).Controller).Container.CEF;
              % 2. Find which element of the DOM we want to edit (as before):
              data_tag = char(struct(app.ListBox).Controller.ProxyView.PeerNode.getId);    
              % 3. Manipulate the DOM via a JS command
              rez = win.executeJS(['dojo.style(dojo.query("[data-tag^=''' ...
                data_tag ''']")[0],"textAlign","center")']);
            catch
              pause(1); % Give the figure (webpage) some more time to load
            end
          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 = [100 100 260 147];
            app.UIFigure.Name = 'UI Figure';
            setAutoResize(app, app.UIFigure, true)

            % Create LabelListBox
            app.LabelListBox = uilabel(app.UIFigure);
            app.LabelListBox.HorizontalAlignment = 'right';
            app.LabelListBox.Position = [50 93 44 15];
            app.LabelListBox.Text = 'List Box';

            % Create ListBox
            app.ListBox = uilistbox(app.UIFigure);
            app.ListBox.Position = [109 36 100 74];

        end
    end

    methods (Access = public)

        % Construct app
        function app = domDemo()

            % Create and configure components
            createComponents(app)

            % Register the app with App Designer
            registerApp(app, app.UIFigure)

            % Execute the startup function
            runStartupFcn(app, @startupFcn)

            if nargout == 0
                clear app
            end
        end

        % Code that executes before app deletion
        function delete(app)

            % Delete UIFigure when app is deleted
            delete(app.UIFigure)
        end
    end
end