MATLAB: (App Designer) Dropdown menu detect variables in workspace.

app designer

I'm try to familiar myself with apps designer. How to create a dropdown menu with the list of variables in workspace. so, user only choose their selected variable/dataset.

Best Answer

Yes, it is possible. Here is one way. Add a drop-down menu to the app. In the COMPONENT BROWSER right-click app.UIFigure and add a startupFcn callback for figure object. You can define the newly created function like this

function startupFcn(app)
  vars = evalin('base', 'whos');
  cell_array = cell(size(vars));
  for i=1:length(vars)
    cell_array{i} = vars(i).name;
  end
  app.DropDown.Items = cell_array;
end

where DropDown is the name of your drop-down menu. Now start the app, the drop-down menu will enlist all the variables from the workspace.

Related Solutions

MATLAB: Hi guys, I’m trying to create a multiwindow app. It’s the first app but I’m taking this error. How to solve it

I beleive your error is here

% Code that executes after component creation
        function startupFcn(app, MainApp, a, b, c)
            % Store main app in property for CloseRequestFcn to use
            app.CallingApp = mainApp;    % <----------------------------- HERE

Should be

            app.CallingApp = MainApp;   % with capital M

Make that change, save the app, close the app, restart it, and test it. If the problem persists, I'd be glad to look further.

MATLAB: CellSelectionCallback-update column name

Well, yes, for what you want to do to work, you need a way to update your UI_Column dialog whenever your CellSelectionCallback is called. At the moment, there's nothing that tells the dialog that the selection has changed.

One way to do that is to keep around the handle to the edit control in that dialog and update it in the CellSelectionCallback:

classdef app2 < matlab.apps.AppBase
    % Properties that correspond to app components
    properties (Access = public)
        UIFigure              matlab.ui.Figure
        Panel                 matlab.ui.container.Panel
        addrowButton          matlab.ui.control.Button
        UITable               matlab.ui.control.Table
        addcolumnButton       matlab.ui.control.Button
        editnamecolumnButton  matlab.ui.control.Button
    end
    properties (Access = private)
        Data_temp=[] % Description
        UI_ColumnOldName;   % UItextarea for Selecting column name to edit
        UI_ColumnNewName;   % UItextarea for input of new column name
    end
    methods (Access = private)   
        function name_col(app,new_name) % new name column

                 app.UITable.ColumnName{(app.Data_temp(2))}=char(new_name.Value);
        end        
        function SetSelectionName(app) % select old name column
            if isgraphics(app.UI_ColumnOldName)   %edit dialog is not live is the handle is not valid
                app.UI_ColumnOldName.Value = app.UITable.ColumnName{(app.Data_temp(2))};
                app.UI_ColumnNewName.Value = app.UI_ColumnOldName.Value;
            end
        end        
    end
    methods (Access = private)
        % Code that executes after component creation
        function startupFcn(app)
            app.UITable.Data=cell(10,3); % default table
            app.UITable.ColumnEditable=true; 
            app.UITable.ColumnName ={'A','B','C'}; % default name
        end
        % Cell selection callback: UITablea
        function UITableCellSelection(app, event)
            app.Data_temp=event.Indices; % salva gli indici nella proprietà Data_temp (creata dall'utente)UITableCellSelection(app);
            app.SetSelectionName;
            
        end
        % Button pushed function: addcolumnButton
        function addcolumn_ButtonPushed(app, ~)
                 app.UITable.Data(:,end+1)={''}; % add column
                 column_name=char(inputdlg('column name'));
                 app.UITable.ColumnName{end+1}=column_name;
        end
        % Button pushed function: addrowButton
        function addrow_ButtonPushed(app, ~)
               app.UITable.Data(end+1,:)={''}; % add row below
        end
        % Button pushed function: editnamecolumnButton
        function editnamecolumn_ButtonPushed(app, ~)
            
            if isempty(app.Data_temp)
                 warndlg('select a cell below the desidered column'); % warning: app.Data_temp is empty
                 
            else
                UI_Column=uifigure('Name','Column Name','Position',[100 100 429 276]);
                app.UI_ColumnOldName=uitextarea(UI_Column,'Position',[100 140 100 22]);
                app.UI_ColumnNewName=uitextarea(UI_Column,'Position',[220 140 100 22]); % new name column
                UI_label=uilabel(UI_Column,'Text','new column name','Position',[220 165 100 22]);
                UI_label_2=uilabel(UI_Column,'Text','old column name','Position',[100 165 100 22]);
                UI_save=uibutton(UI_Column,'Text','Save','Position',[220 100 100 22],'ButtonPushedFcn',@(UI_save,event) name_col(app,new_name)); % change and save new column name                                
                app.SetSelectionName;  %update textarea controls
            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 = [100 100 697 560];
            app.UIFigure.Name = 'UI Figure';
            % Create Panel
            app.Panel = uipanel(app.UIFigure);
            app.Panel.Title = 'Panel';
            app.Panel.Position = [114 113 495 382];
            % Create addrowButton
            app.addrowButton = uibutton(app.Panel, 'push');
            app.addrowButton.ButtonPushedFcn = createCallbackFcn(app, @addrow_ButtonPushed, true);
            app.addrowButton.Position = [23 271 100 22];
            app.addrowButton.Text = 'add row';
            % Create UITable
            app.UITable = uitable(app.Panel);
            app.UITable.ColumnName = {'Column 1'; 'Column 2'};
            app.UITable.RowName = {};
            app.UITable.CellSelectionCallback = createCallbackFcn(app, @UITableCellSelection, true);
            app.UITable.Position = [152 108 302 185];
            % Create addcolumnButton
            app.addcolumnButton = uibutton(app.Panel, 'push');
            app.addcolumnButton.ButtonPushedFcn = createCallbackFcn(app, @addcolumn_ButtonPushed, true);
            app.addcolumnButton.Position = [24 230 100 22];
            app.addcolumnButton.Text = 'add column';
            % Create editnamecolumnButton
            app.editnamecolumnButton = uibutton(app.Panel, 'push');
            app.editnamecolumnButton.ButtonPushedFcn = createCallbackFcn(app, @editnamecolumn_ButtonPushed, true);
            app.editnamecolumnButton.Position = [19 189 112 22];
            app.editnamecolumnButton.Text = 'edit name column';
        end
    end
    methods (Access = public)
        % Construct app
        function app = app2
            % 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

Best Answer

Related Solutions

MATLAB: Hi guys, I’m trying to create a multiwindow app. It’s the first app but I’m taking this error. How to solve it

MATLAB: CellSelect​ionCallbac​k-update column name

Related Question

MATLAB: CellSelectionCallback-update column name