ListBox

Value, specified as an element of the Items array, ItemsData array, or an empty cell array. By default, Value is the first element in Items.

To specify no selection, set Value to an empty cell array.

Specifying Value as an element of Items selects the list item that matches that element. If ItemsData is not empty, then Value must be set to an element of ItemsData, and the list box will select the associated item in the list.

List box items, specified as a cell array of character vectors, string array, or 1-D categorical array. Duplicate elements are allowed. The list box displays as many options as there are elements in the Items array. If you specify this property as a categorical array, MATLAB^® uses the values in the array, not the full set of categories.

Data associated with each element of the Items property value, specified as a 1-by-n numeric array or a 1-by-n cell array. Duplicate elements are allowed.

For example, if you set the Items value to employee names, you might set the ItemsData value to corresponding employee ID numbers. The ItemsData value is not visible to the app user.

If the number of array elements in the ItemsData value and the Items value do not match, one of the following occurs:

Example: {'One','Two','Three'}

Example: [10 20 30 40]

Index of the component value in the list of items or item data, specified as a positive integer.

To specify no selection, set ValueIndex to an empty array ([]).

In most cases, you can use the Value property to query and update the component value. However, the ValueIndex property can be useful when both the Items and ItemsData properties are nonempty. In this case, you can use the ValueIndex property to query the element of Items that corresponds to the current value.

fig = uifigure;
lb = uilistbox(fig, ...
    "Items",["Red","Green","Blue"], ...
    "ItemsData",["#F00","#0F0","#00F"]);
idx = lb.ValueIndex;
 
disp(lb.Items(idx) + ": " + lb.Value)

Red: #F00

Font name, specified as a system supported font name. The default font depends on the specific operating system and locale.

If the specified font is not available, then MATLAB uses the best match among the fonts available on the system where the app is running.

Example: 'Arial'

Font size, specified as a positive number. The units of measurement are pixels. The default font size depends on the specific operating system and locale.

Example: 14

Font weight, specified as one of these values:

Not all fonts have a bold font weight. For fonts that do not, specifying 'bold' results in the normal font weight.

Font angle, specified as 'normal' or 'italic'. Not all fonts have an italic font angle. For fonts that do not, specifying 'italic' results in the normal font angle.

Font color, specified as an RGB triplet, a hexadecimal color code, or one of the options listed in the table.

RGB triplets and hexadecimal color codes are useful for specifying custom colors.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and hexadecimal color codes.

Here are the RGB triplets and hexadecimal color codes for the default colors MATLAB uses in many types of plots.

Background color, specified as an RGB triplet, a hexadecimal color code, or one of the color options listed in the table.

RGB triplets and hexadecimal color codes are useful for specifying custom colors.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and hexadecimal color codes.

Here are the RGB triplets and hexadecimal color codes for the default colors MATLAB uses in many types of plots.

This property is read-only.

Configuration of added styles created using the uistyle function, returned as an n-by-3 table array. Each row of the table array corresponds to a style that is currently applied to the list box. Styles that are added consecutively are given a style order number of n+1. The Target and TargetIndex columns specify the part of the list box that the style was added to. The Style column specifies the style class name.

Use this property if you want to remove a style from the list box using the removeStyle function.

Example: Remove a Style

First, add two styles to a list box.

fig = uifigure;
fig.Position = [100 100 300 250];
lb = uilistbox(fig);

s1 = uistyle("FontColor","blue");
s2 = uistyle("FontColor","red");

addStyle(lb,s1,"item",1);
addStyle(lb,s2,"item",[2 3 4]);

When you query lb.StyleConfigurations, MATLAB returns a 2-by-3 table array. The blue font style was added to the list box first, so it is style order number 1. The TargetIndex value for the level style, {[ 1]}, indicates that the style was applied to the first item in the list box. Similarly, the second style was added to the last three items in the list box.

lb.StyleConfigurations

ans =

  2×3 table

         Target    TargetIndex              Style          
         ______    ___________    _________________________

    1     item      {[    1]}     1×1 matlab.ui.style.Style
    2     item      {[2 3 4]}     1×1 matlab.ui.style.Style

Remove the second style that was added to the list box by specifying style order number 2. The component appearance updates to use only the first style.

removeStyle(lb,2)

State of visibility, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

To make your app start faster, set the Visible property to 'off' for all UI components that do not need to appear at startup.

Multiple item selection, specified as 'off' or 'on', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Set this property to 'on' to allow users to select multiple items simultaneously.

Operational state, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

Tooltip, specified as a character vector, cell array of character vectors, string array, or 1-D categorical array. Use this property to display a message when the user hovers the pointer over the component at run time. The tooltip displays even when the component is disabled. To display multiple lines of text, specify a cell array of character vectors or a string array. Each element in the array becomes a separate line of text. If you specify this property as a categorical array, MATLAB uses the values in the array, not the full set of categories.

Context menu, specified as a ContextMenu object created using the uicontextmenu function. Use this property to display a context menu when you right-click on a component.

Location and size of the list box relative to the parent container, specified as the vector [left bottom width height]. This table describes each element in the vector.

All measurements are in pixel units.

The Position values are relative to the drawable area of the parent container. The drawable area is the area inside the borders of the container and does not include the area occupied by decorations such as a menu bar or title.

Example: [100 100 100 200]

Inner location and size of list box, specified as [left bottom width height]. Position values are relative to the parent container. All measurements are in pixel units. This property value is identical to the Position property.

This property is read-only.

Outer location and size of list box returned as [left bottom width height]. Position values are relative to the parent container. All measurements are in pixel units. This property value is identical to the Position property.

Layout options, specified as a GridLayoutOptions object. This property specifies options for components that are children of grid layout containers. If the component is not a child of a grid layout container (for example, it is a child of a figure or panel), then this property is empty and has no effect. However, if the component is a child of a grid layout container, you can place the component in the desired row and column of the grid by setting the Row and Column properties on the GridLayoutOptions object.

For example, this code places a list box in the third row and second column of its parent grid.

g = uigridlayout([4 3]);
list = uilistbox(g);
list.Layout.Row = 3;
list.Layout.Column = 2;

To make the list box span multiple rows or columns, specify the Row or Column property as a two-element vector. For example, this list box spans columns 2 through 3:

list.Layout.Column = [2 3];

Value changed callback, specified as one of these values:

This callback function executes when the user selects a different item in the list box. It does not execute if the Value property setting changes programmatically.

This callback function can access specific information about the user’s interaction with the list box. MATLAB passes this information in a ValueChangedData object as the second argument to your callback function. In App Designer, the argument is called event. You can query the object properties using dot notation. For example, event.PreviousValue returns the previous value of the list box. The ValueChangedData object is not available to callback functions specified as character vectors.

The following table lists the properties of the ValueChangedData object.

For more information about writing callbacks, see Callbacks in App Designer.

Clicked callback, specified as one of these values:

This callback function executes when the user clicks anywhere in the list box.

This callback function can access specific information about the user’s interaction with the list box. MATLAB passes this information in a ClickedData object as the second argument to your callback function. In App Designer, the argument is called event. You can query the object properties using dot notation. For example, event.InteractionInformation returns information about where the user clicked in the list box. The ClickedData object is not available to callback functions specified as character vectors.

This table lists the properties of the ClickedData object.

This table lists the properties of the InteractionInformation object associated with the list box component.

For more information about writing callbacks, see Callbacks in App Designer.

Example: Open Window When List Box Is Clicked

Create a list box with items that represent colors. Specify a ClickedFcn callback function named openWindow that executes when a user clicks the list box. In the openWindow function:

To try this example, save the code in a new script and run it. Click an item in the list box to open a new window.

fig = uifigure;
lb = uilistbox(fig);
lb.Items = ["Red","Yellow","Blue"];
lb.ItemsData = ["r","y","b"];
lb.ClickedFcn = @openWindow;

function openWindow(lb,event)
idx = event.InteractionInformation.Item;
if ~isempty(idx)
    p = event.InteractionInformation.ScreenLocation;
    color = lb.ItemsData(idx);
    fig2 = uifigure("Position",[p 150 150]);
    fig2.Color = color;
end
end

Double-clicked callback, specified as one of these values:

This callback function executes when the user double-clicks anywhere in the list box.

This callback function can access specific information about the user’s interaction with the list box. MATLAB passes this information in a DoubleClickedData object as the second argument to your callback function. In App Designer, the argument is called event. You can query the object properties using dot notation. For example, event.InteractionInformation returns information about where the user double-clicked in the list box. The DoubleClickedData object is not available to callback functions specified as character vectors.

This table lists the properties of the DoubleClickedData object.

This table lists the properties of the InteractionInformation object associated with the list box component.

For more information about writing callbacks, see Callbacks in App Designer.

Example: Open Window When List Box Is Double-Clicked

Create a list box with items that represent colors. Specify a DoubleClickedFcn callback function named openWindow that executes when a user double-clicks the list box. In the openWindow function:

To try this example, save the code in a new script and run it. Double-click an item in the list box to open a new window.

fig = uifigure;
lb = uilistbox(fig);
lb.Items = ["Red","Yellow","Blue"];
lb.ItemsData = ["r","y","b"];
lb.DoubleClickedFcn = @openWindow;

function openWindow(lb,event)
idx = event.InteractionInformation.Item;
if ~isempty(idx)
    p = event.InteractionInformation.ScreenLocation;
    color = lb.ItemsData(idx);
    fig2 = uifigure("Position",[p 150 150]);
    fig2.Color = color;
end
end

Object creation function, specified as one of these values:

For more information about specifying a callback as a function handle, cell array, or character vector, see Callbacks in App Designer.

This property specifies a callback function to execute when MATLAB creates the object. MATLAB initializes all property values before executing the CreateFcn callback. If you do not specify the CreateFcn property, then MATLAB executes a default creation function.

Setting the CreateFcn property on an existing component has no effect.

If you specify this property as a function handle or cell array, you can access the object that is being created using the first argument of the callback function. Otherwise, use the gcbo function to access the object.

Object deletion function, specified as one of these values:

For more information about specifying a callback as a function handle, cell array, or character vector, see Callbacks in App Designer.

This property specifies a callback function to execute when MATLAB deletes the object. MATLAB executes the DeleteFcn callback before destroying the properties of the object. If you do not specify the DeleteFcn property, then MATLAB executes a default deletion function.

If you specify this property as a function handle or cell array, you can access the object that is being deleted using the first argument of the callback function. Otherwise, use the gcbo function to access the object.

Callback interruption, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

This property determines if a running callback can be interrupted. There are two callback states to consider:

MATLAB determines callback interruption behavior whenever it executes a command that processes the callback queue. These commands include drawnow, figure, uifigure, getframe, waitfor, and pause.

If the running callback does not contain one of these commands, then no interruption occurs. MATLAB first finishes executing the running callback, and later executes the interrupting callback.

If the running callback does contain one of these commands, then the Interruptible property of the object that owns the running callback determines if the interruption occurs:

Callback queuing, specified as 'queue' or 'cancel'. The BusyAction property determines how MATLAB handles the execution of interrupting callbacks. There are two callback states to consider:

The BusyAction property determines callback queuing behavior only when both of these conditions are met:

Under these conditions, the BusyAction property of the object that owns the interrupting callback determines how MATLAB handles the interrupting callback. These are possible values of the BusyAction property:

This property is read-only.

Deletion status, returned as an on/off logical value of type matlab.lang.OnOffSwitchState.

MATLAB sets the BeingDeleted property to 'on' when the DeleteFcn callback begins execution. The BeingDeleted property remains set to 'on' until the component object no longer exists.

Check the value of the BeingDeleted property to verify that the object is not about to be deleted before querying or modifying it.

Parent container, specified as a Figure object created using the uifigure function, or one of its child containers: Tab, Panel, ButtonGroup, or GridLayout. If no container is specified, MATLAB calls the uifigure function to create a new Figure object that serves as the parent container.

Visibility of the object handle, specified as 'on', 'callback', or 'off'.

This property controls the visibility of the object in its parent's list of children. When an object is not visible in its parent's list of children, it is not returned by functions that obtain objects by searching the object hierarchy or querying properties. These functions include get, findobj, clf, and close. Objects are valid even if they are not visible. If you can access an object, you can set and get its properties, and pass it to any function that operates on objects.

This property is read-only.

Type of graphics object, returned as 'uilistbox'.

Object identifier, specified as a character vector or string scalar. You can specify a unique Tag value to serve as an identifier for an object. When you need access to the object elsewhere in your code, you can use the findobj function to search for the object based on the Tag value.

User data, specified as any MATLAB array. For example, you can specify a scalar, vector, matrix, cell array, character array, table, or structure. Use this property to store arbitrary data on an object.

If you are working in App Designer, create public or private properties in the app to share data instead of using the UserData property. For more information, see Share Data Within App Designer Apps.