如何以比官方記錄更多的方式自定義App Designer數據？

Question

最近在UndocumentedMatlab上發表的一篇文章提到App Designer圖實際上是使用Dojo Toolkit的網頁。 這意味着我們理論上可以直接操作HTML DOM來實現某些不可用的UI自定義。

下面是App Designer圖形定義的示例，如App Designer生成的.m文件中所示（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

......看起來像這樣：

根據uilistbox的文檔（它將我們重定向到完整屬性列表的復選框屬性頁面），沒有辦法操縱例如列表項的文本對齊。 如果是這樣的話，

問題 ：我們如何操作示例應用程序中的ListBox ，使其內容成為中心對齊，即使我們無法使用這樣的設置？

Answer 1

為了成功完成這項任務，我們需要以下幾點：

• 找到HTML / CSS所在的位置（以便我們可以操作它們）。
• 找到我們要編輯的DOM的哪個元素。
• 找出我們需要做出的改變。
• 找到一種使用MATLAB操作元素的方法。

---

一步一步地工作：

1.找到圖形的HTML / CSS存儲/定位的位置

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

2.找到我們需要編輯的DOM的哪個元素

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

使用瀏覽器驗證：

3.找出我們需要做出的改變

由於我們想要操縱文本對齊，我們會搜索一些相關的關鍵字並找到CSS text-align屬性 。 然后我們手動嘗試看它是否真的有效：

4.找到一種使用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")']);

---

這個答案的完整代碼：

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