TextArea

Text area UI component

• 

×

Description

A text area UI component allows an app user to enter multiple lines of text in an app. Use the TextArea object to modify the appearance and behavior of a text area after you create it.

Creation

Create a text area in an app using the uitextarea function.

Properties

Text

Value — Value

{''} (default) | character vector | string scalar | cell array of character vectors | string array | 1-D categorical array

Value, specified as a character vector, string scalar, cell array of character vectors, string array, or 1-D categorical array. To display multiple lines of text, specify Value as an array. Each element in the array represents a separate line of text.

txt = ["Line 1"; "Line 2"; "Line 3"; "Line 4"];
textarea = uitextarea("Value",txt);

If you specify this property as a categorical array, MATLAB^® uses the values in the array, not the full set of categories.

If the text does not fit into the width of the text area, MATLAB wraps the text.

If there are too many rows to display in the text area, MATLAB adds a scroll bar.

Example: ["Joseph Welford"; "Mary Reilly"; "Roberta Silberlicht"]

Placeholder — Placeholder text in text area

'' (default) | character vector | string scalar

Placeholder text in the text area, specified as a character vector or string scalar. The placeholder provides a short hint to describe the expected input. The text shows only when the Value property is {''}.

Example: 'Enter text'

HorizontalAlignment — Horizontal alignment of text within text area

'left' (default) | 'right' | 'center'

Alignment of text within the text area, specified as 'left', 'right', or 'center'. The alignment affects the display as the app user edits the text area and how MATLAB displays the text in the app.

WordWrap — Word wrapping to fit component width

'on' (default) | on/off logical value

Word wrapping to fit component width, 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.

Use this property to prevent text from getting clipped horizontally when the width of the component is smaller than the text you want to display.

• 'on' — Breaks text into new lines so that each line fits within the width of the component, and avoids breaking words when possible.

• 'off' — Text does not wrap.

Font and Color

FontName — Font name

system supported font name

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'

FontSize — Font size

positive number

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

FontWeight — Font weight

'normal' (default) | 'bold'

Font weight, specified as one of these values:

• 'normal' — Default weight as defined by the particular font

• 'bold' — Thicker character outlines than 'normal'

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

FontAngle — Font angle

'normal' (default) | 'italic'

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.

FontColor — Font color

[0 0 0] (default) | RGB triplet | hexadecimal color code | 'r' | 'g' | 'b' | ...

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.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1]; for example, [0.4 0.6 0.7].

• A hexadecimal color code is a character vector or a string scalar that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Thus, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

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

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"

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

RGB Triplet	Hexadecimal Color Code	Appearance
[0 0.4470 0.7410]	"#0072BD"
[0.8500 0.3250 0.0980]	"#D95319"
[0.9290 0.6940 0.1250]	"#EDB120"
[0.4940 0.1840 0.5560]	"#7E2F8E"
[0.4660 0.6740 0.1880]	"#77AC30"
[0.3010 0.7450 0.9330]	"#4DBEEE"
[0.6350 0.0780 0.1840]	"#A2142F"

BackgroundColor — Background color

[1 1 1] (default) | RGB triplet | hexadecimal color code | 'r' | 'g' | 'b' | ...

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.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1]; for example, [0.4 0.6 0.7].

• A hexadecimal color code is a character vector or a string scalar that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Thus, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

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

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"

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

RGB Triplet	Hexadecimal Color Code	Appearance
[0 0.4470 0.7410]	"#0072BD"
[0.8500 0.3250 0.0980]	"#D95319"
[0.9290 0.6940 0.1250]	"#EDB120"
[0.4940 0.1840 0.5560]	"#7E2F8E"
[0.4660 0.6740 0.1880]	"#77AC30"
[0.3010 0.7450 0.9330]	"#4DBEEE"
[0.6350 0.0780 0.1840]	"#A2142F"

Interactivity

Visible — State of visibility

'on' (default) | on/off logical value

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.

• 'on' — Display the object.

• 'off' — Hide the object without deleting it. You still can access the properties of an invisible UI component.

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

Editable — Editability of text area

'on' (default) | on/off logical value

Editability of the text area, 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.

Use this property in combination with the Enable property value to determine if and how the component responds to app user input:

• To make the text area editable and the associated callback triggerable, set both the Enable property and the Editable property values to 'on'.

  

• To make the text area uneditable, but the text easy to read, set the Enable property value to 'on' and the Editable property value to 'off'.

  

• To make the text area uneditable and the text dimmed, set both properties to 'off'.

  

Enable — Operational state of text area

'on' (default) | on/off logical value

Operational state of the text area, 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.

Use this property in combination with the Editable property value to determine if and how the component responds to app user input:

• To make the text area editable and the associated callback triggerable, set both the Enable property and the Editable property values to 'on'.

  

• To make the text area uneditable, but the text easy to read, set the Enable property value to 'on' and the Editable property value to 'off'.

  

• To make the text area uneditable and the text dimmed, set both properties to 'off'.

  

Tooltip — Tooltip

'' (default) | character vector | cell array of character vectors | string array | 1-D categorical array

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.

ContextMenu — Context menu

empty GraphicsPlaceholder array (default) | ContextMenu object

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.

Position

Position — Location and size of text area

[100 100 150 60] (default) | [left bottom width height]

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

Element	Description
left	Distance from the inner left edge of the parent container to the outer left edge of the text area
bottom	Distance from the inner bottom edge of the parent container to the outer bottom edge of the text area
width	Distance between the right and left outer edges of the text area
height	Distance between the top and bottom outer edges of the text area

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 90]

InnerPosition — Inner location and size of text area

[100 100 150 60] (default) | [left bottom width height]

Inner location and size of the text area, 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.

OuterPosition — Outer location and size of text area

[100 100 150 60] (default) | [left bottom width height]

This property is read-only.

Outer location and size of the text area 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 — Layout options

empty LayoutOptions array (default) | GridLayoutOptions object

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 text area in the third row and second column of its parent grid.

g = uigridlayout([4 3]);
tarea = uitextarea(g);
tarea.Layout.Row = 3;
tarea.Layout.Column = 2;

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

tarea.Layout.Column = [2 3];

Callbacks

ValueChangedFcn — Value changed callback

'' (default) | function handle | cell array | character vector

Value changed callback, specified as one of these values:

• A function handle.

• A cell array in which the first element is a function handle. Subsequent elements in the cell array are the arguments to pass to the callback function.

• A character vector containing a valid MATLAB expression (not recommended). MATLAB evaluates this expression in the base workspace.

The callback executes when the user changes the text and either presses Tab or clicks outside the text area. It does not execute if the Value property changes programmatically.

This callback function can access specific information about the user’s interaction with the text area. 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 text area. The ValueChangedData object is not available to callback functions specified as character vectors.

The following table lists the properties of the ValueChangedData object.

Property	Value
Value	Value of text area after app user’s most recent interaction with it
PreviousValue	Value of text area before app user’s most recent interaction with it
Source	Component that executes the callback
EventName	'ValueChanged'

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

ValueChangingFcn — Value changing callback

'' (default) | function handle | cell array | character vector

Value changing callback, specified as one of these values:

• A function handle.

• A cell array in which the first element is a function handle. Subsequent elements in the cell array are the arguments to pass to the callback function.

• A character vector containing a valid MATLAB expression (not recommended). MATLAB evaluates this expression in the base workspace.

This callback executes as follows:

• As the user types in the text area, the callback executes repeatedly.

• When the user presses Tab or clicks outside the text area, the callback executes.

If the text area value changes programmatically, then the callback does not execute.

This callback function can access specific information about the user’s interaction with the text area. MATLAB passes this information in a ValueChangingData 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.Value is the value in the text area that triggered the execution of the callback. The ValueChangingData object is not available to callback functions specified as character vectors.

Here are the properties of the ValueChangingData object:

Property	Description
Value	Value that triggered the execution of the callback
Source	Component that executes the callback
EventName	'ValueChanging'

The Value property of the TextArea object is not updated until the user either presses Tab or clicks outside the text area. However, you can get the text while the user is still typing by querying the Value property of the ValueChangingData object.

Note

Avoid updating the Value property of the TextArea object from within its own ValueChangingFcn callback, as this might result in unexpected behavior. To update the text area value in response to user input, use a ValueChangedFcn callback instead.

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

CreateFcn — Creation function

'' (default) | function handle | cell array | character vector

Object creation function, specified as one of these values:

• Function handle.

• Cell array in which the first element is a function handle. Subsequent elements in the cell array are the arguments to pass to the callback function.

• Character vector containing a valid MATLAB expression (not recommended). MATLAB evaluates this expression in the base workspace.

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.

DeleteFcn — Deletion function

'' (default) | function handle | cell array | character vector

Object deletion function, specified as one of these values:

• Function handle.

• Cell array in which the first element is a function handle. Subsequent elements in the cell array are the arguments to pass to the callback function.

• Character vector containing a valid MATLAB expression (not recommended). MATLAB evaluates this expression in the base workspace.

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 Execution Control

Interruptible — Callback interruption

'on' (default) | on/off logical value

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:

• The running callback is the currently executing callback.

• The interrupting callback is a callback that tries to interrupt the running callback.

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:

• If the value of Interruptible is 'off', then no interruption occurs. Instead, the BusyAction property of the object that owns the interrupting callback determines if the interrupting callback is discarded or added to the callback queue.

• If the value of Interruptible is 'on', then the interruption occurs. The next time MATLAB processes the callback queue, it stops the execution of the running callback and executes the interrupting callback. After the interrupting callback completes, MATLAB then resumes executing the running callback.

Note

Callback interruption and execution behave differently in these situations:

• If the interrupting callback is a DeleteFcn, CloseRequestFcn, or SizeChangedFcn callback, then the interruption occurs regardless of the Interruptible property value.

• If the running callback is currently executing the waitfor function, then the interruption occurs regardless of the Interruptible property value.

• If the interrupting callback is owned by a Timer object, then the callback executes according to schedule regardless of the Interruptible property value.

Note

When an interruption occurs, MATLAB does not save the state of properties or the display. For example, the object returned by the gca or gcf command might change when another callback executes.

BusyAction — Callback queuing

'queue' (default) | 'cancel'

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 running callback is the currently executing callback.

• The interrupting callback is a callback that tries to interrupt the running callback.

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

• The running callback contains a command that processes the callback queue, such as drawnow, figure, uifigure, getframe, waitfor, or pause.

• The value of the Interruptible property of the object that owns the running callback is 'off'.

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:

• 'queue' — Puts the interrupting callback in a queue to be processed after the running callback finishes execution.

• 'cancel' — Does not execute the interrupting callback.

BeingDeleted — Deletion status

on/off logical value

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/Child

Parent — Parent container

Figure object (default) | Panel object | Tab object | ButtonGroup object | GridLayout object

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.

HandleVisibility — Visibility of object handle

'on' (default) | 'callback' | 'off'

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.

HandleVisibility Value	Description
'on'	The object is always visible.
'callback'	The object is visible from within callbacks or functions invoked by callbacks, but not from within functions invoked from the command line. This option blocks access to the object at the command-line, but allows callback functions to access it.
'off'	The object is invisible at all times. This option is useful for preventing unintended changes to the UI by another function. Set the HandleVisibility to 'off' to temporarily hide the object during the execution of that function.

Identifiers

Type — Type of graphics object

'uitextarea'

This property is read-only.

Type of graphics object, returned as 'uitextarea'.

Tag — Object identifier

'' (default) | character vector | string scalar

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.

UserData — User data

[] (default) | array

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.

Object Functions

scroll	Scroll to location within component
focus	Focus UI component

Examples

Set and Access Text Area Properties

Create a populated text area in a UI figure.

fig = uifigure;
txa = uitextarea(fig, ...
    "Value",["First Name Last Name"; "Address 1"; ...
    "Address 2"; "City, State"; "Postal Code"]);

Notice that the text area includes a scroll bar so that the app user can view the postal code.

Determine the current width and height of the text area by querying the third and fourth values of the Position property.

size = txa.Position(3:4)

size = 1×2

   150    60

Increase the text area size so that all of the content is visible without the use of a scroll bar.

txa.Position(3:4) = [155 80];

Scroll Text Area Programmatically

Scroll to the bottom of a text area programmatically.

Create a text area. Specify a size and long text for it.

fig = uifigure;
txa = uitextarea(fig);
txa.Position = [100 100 80 80];
txa.Value = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor.";

Scroll to the bottom of the text area.

scroll(txa,"bottom")

Code Response to Changed Text Area Value

Create an app that enables a button when an app user enters text in a text area.

In a file named textAreaApp.m, write a function that implements the app:

• Create a UI figure and a grid layout manager to lay out the app.

• Create a label, text area, and button in the grid layout manager.

• Write a callback function named textEntered that enables a button when there is text in the text area, and assign the function to the ValueChangedFcn callback property of the text area. For more information about callbacks, see Create Callbacks for Apps Created Programmatically.

function textAreaApp
fig = uifigure;
g = uigridlayout(fig,[3 3]);
g.RowHeight = {'fit','fit','fit'};
g.ColumnWidth = {'1x','fit','1x'};

lbl = uilabel(g,"Text","Enter Comments:");
lbl.Layout.Row = 1;
lbl.Layout.Column = 2;
txa = uitextarea(g);
txa.Layout.Row = 2;
txa.Layout.Column = 2;
btn = uibutton(g,"Text","Submit","Enable","off");
btn.Layout.Row = 3;
btn.Layout.Column = 2;

txa.ValueChangedFcn = @(src,event) textEntered(src,event,btn);
end

function textEntered(src,event,btn)
val = src.Value;
btn.Enable = "off";
% Check each element of text area cell array for text
for k = 1:length(val)
    if ~isempty(val{k})
        btn.Enable = "on";
        break
    end
end
end

Run the textAreaApp function. Enter some text in the text area, then click outside the text area to enable the Submit button.

Version History

Introduced in R2016a

R2021b: Program response while a user is typing

Create a ValueChangingFcn callback to program your app to respond when a user is typing in a text area. The callback function executes repeatedly while the user types.

R2021a: Specify placeholder text

Provide a short hint that describes the expected text area input by using the Placeholder property.

R2020b: Toggle text wrapping

Use the WordWrap property to toggle text wrapping. When the WordWrap property is 'on' (the default), the UI component breaks the text into new lines so that each line fits horizontally within the component. When the property is set to 'off', the text does not wrap.