bat365 Homepage

uialert

Display alert dialog box

Syntax

uialert(fig,message,title)

uialert(___,Name,Value)

Description

uialert(fig,message,title) displays a modal dialog box in front of the specified figure window. The figure must be created with the uifigure function. The dialog box displays the specified message and has a title bar with the specified title. By default, the dialog box also contains an error icon and an OK button.

example

uialert(___,Name,Value) displays a dialog box with properties specified by one or more Name,Value arguments.

Examples

collapse all

Alert App User to Error

Create a modal alert dialog box. The figure behind it is inaccessible until you close the dialog box.

fig = uifigure;
uialert(fig,"File not found.","Invalid File");

Alert dialog box. The icon is a red octagon with an exclamation point. The title of the dialog box is "Invalid File" and the text is "File not found". The box has an OK button in the bottom right.

Create Multiline Modal Alert Dialog Box with Warning Icon

fig = uifigure;
message = ["Fire hazard!","Consider reducing temperature."];
uialert(fig,message,"Warning", ...
    "Icon","warning");

Warning dialog box. The text spans two lines. The first line says "Fire hazard!" and the second line says "Consider reducing temperature".

Display Formatted MATLAB Error

Create a figure and two matrices of different sizes.

fig = uifigure; 
A = rand(3);
B = ones(5);

Attempt to vertically concatenate the matrices. Handle any errors that occur by getting the error text and creating an alert dialog box in the figure, and then specify the error text as the dialog message. MATLAB^® error text often includes HTML formatting, so specify the dialog interpreter as 'html'. The error is displayed with a link to the documentation for the vertcat function.

try 
    C = vertcat(A,B);
catch ME 
    report = getReport(ME);
    uialert(fig,report,"Error Message","Interpreter","html");
end

Alert dialog box. The message says: "Error using vertcat. Dimensions of arrays being concatenated are not consistent". The word "vertcat" is a blue hyperlink.

Input Arguments

collapse all

`fig` — Target figure
`Figure` object

Target figure, specified as a Figure object. The figure must be created with the uifigure function.

`message` — Message
character vector | cell array of character vectors | string array

Message, specified as a character vector, cell array of character vectors, or string array. The message can be any length.

To display multiple lines of text, use a cell array of character vectors or a string array, where each element in the array is a different line of text.

Example: 'Invalid value'

`title` — Title
character vector | string scalar

Title, specified as a character vector or string scalar. Long titles truncate and are followed by ellipses. The exact length at which a title is truncated depends on your system setup.

Spaces replace format characters, such as the newline (\n) character.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: 'Icon','warning'

`CloseFcn` — Alert dialog box close request function callback
`''` (default) | function handle | cell array | character vector

The alert dialog box close request callback 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 that is a valid MATLAB expression. MATLAB evaluates this expression in the base workspace.

The CloseFcn callback executes when the app user dismisses the alert dialog box by clicking the close button in the title bar or clicking the OK button. The CloseFcn function also executes when the app user closes the figure window for which the alert dialog box displays from the MATLAB command line. You can close a figure window from the command line using the close function.

`Icon` — Icon
`'error'` (default) | predefined icon | custom icon

Icon, specified as a predefined icon or a custom icon.

Predefined Icon

This table lists the values for the predefined icons. For example, to show the check mark icon, specify the name-value pair 'Icon','success'.

Value	Icon
`'error'` (default)
`'warning'`
`'info'`
`'question'`
`'success'`
`''`	No icon displays.

Custom Icon

Specify a custom icon as one of these values:

A character vector that specifies the file name of an SVG, JPEG, GIF, or PNG image that is on the MATLAB path. Alternatively, you can specify a full path to the image file.
A truecolor image array. See Image Types for more information.

`Interpreter` — Dialog text interpreter
`'none'` (default) | `'tex'` | `'latex'` | `'html'`

Dialog text interpreter, specified as:

'none' — Display literal characters.
'tex'— Interpret text using a subset of TeX markup.
'latex'— Interpret text using a subset of LaTeX markup.
'html'— Interpret text using a subset of HTML markup.

TeX Markup

Use TeX markup to add superscripts and subscripts and to include special characters in the text.

Modifiers remain in effect until the end of the text. Superscripts and subscripts are an exception because they modify only the next character or the characters within the curly braces. When you set the interpreter to 'tex', the supported modifiers are as follows.

Modifier	Description	Example
`^{ }`	Superscript	`'text^{superscript}'`
`_{ }`	Subscript	`'text_{subscript}'`
`\bf`	Bold font	`'\bf text'`
`\it`	Italic font	`'\it text'`
`\sl`	Oblique font (usually the same as italic font)	`'\sl text'`
`\rm`	Normal font	`'\rm text'`
`\fontname{specifier}`	Font name — Replace `specifier` with the name of a font family. You can use this in combination with other modifiers.	`'\fontname{Courier} text'`
`\fontsize{specifier}`	Font size —Replace `specifier` with a numeric scalar value in point units.	`'\fontsize{15} text'`
`\color{specifier}`	Font color — Replace `specifier` with one of these colors: `red`, `green`, `yellow`, `magenta`, `blue`, `black`, `white`, `gray`, `darkGreen`, `orange`, or `lightBlue`.	`'\color{magenta} text'`
`\color[rgb]{specifier}`	Custom font color — Replace `specifier` with a three-element RGB triplet.	`'\color[rgb]{0,0.5,0.5} text'`

This table lists the supported special characters for the 'tex' interpreter.

Character Sequence	Symbol	Character Sequence	Symbol	Character Sequence	Symbol
`\alpha`	α	`\upsilon`	υ	`\sim`	~
`\angle`	∠	`\phi`	ϕ	`\leq`	≤
`\ast`	`*`	`\chi`	χ	`\infty`	∞
`\beta`	β	`\psi`	ψ	`\clubsuit`	♣
`\gamma`	γ	`\omega`	ω	`\diamondsuit`	♦
`\delta`	δ	`\Gamma`	Γ	`\heartsuit`	♥
`\epsilon`	ϵ	`\Delta`	Δ	`\spadesuit`	♠
`\zeta`	ζ	`\Theta`	Θ	`\leftrightarrow`	↔
`\eta`	η	`\Lambda`	Λ	`\leftarrow`	←
`\theta`	θ	`\Xi`	Ξ	`\Leftarrow`	⇐
`\vartheta`	ϑ	`\Pi`	Π	`\uparrow`	↑
`\iota`	ι	`\Sigma`	Σ	`\rightarrow`	→
`\kappa`	κ	`\Upsilon`	ϒ	`\Rightarrow`	⇒
`\lambda`	λ	`\Phi`	Φ	`\downarrow`	↓
`\mu`	µ	`\Psi`	Ψ	`\circ`	º
`\nu`	ν	`\Omega`	Ω	`\pm`	±
`\xi`	ξ	`\forall`	∀	`\geq`	≥
`\pi`	π	`\exists`	∃	`\propto`	∝
`\rho`	ρ	`\ni`	∍	`\partial`	∂
`\sigma`	σ	`\cong`	≅	`\bullet`	•
`\varsigma`	ς	`\approx`	≈	`\div`	÷
`\tau`	τ	`\Re`	ℜ	`\neq`	≠
`\equiv`	≡	`\oplus`	⊕	`\aleph`	ℵ
`\Im`	ℑ	`\cup`	∪	`\wp`	℘
`\otimes`	⊗	`\subseteq`	⊆	`\oslash`	∅
`\cap`	∩	`\in`	∈	`\supseteq`	⊇
`\supset`	⊃	`\lceil`	⌈	`\subset`	⊂
`\int`	∫	`\cdot`	·	`\o`	ο
`\rfloor`	⌋	`\neg`	¬	`\nabla`	∇
`\lfloor`	⌊	`\times`	x	`\ldots`	...
`\perp`	⊥	`\surd`	√	`\prime`	´
`\wedge`	∧	`\varpi`	ϖ	`\0`	∅
`\rceil`	⌉	`\rangle`	〉	`\mid`	\|
`\vee`	∨	`\langle`	〈	`\copyright`	©

LaTeX Markup

Use LaTeX markup to format and display mathematical expressions, equations, and special characters. Use dollar symbols around the marked up text. For example, use '$\int_1^{20} x^2 dx$' for inline mode or '$$\int_1^{20} x^2 dx$$' for display mode.

The displayed text uses the default LaTeX font style. You can use LaTeX markup to change the font style.

MATLAB supports most standard LaTeX math mode commands. For more information, see Supported LaTeX Commands.

HTML Markup

Use HTML markup to display links and customize font styles.

The interpreter supports a subset of HTML markup. As a general guideline, the interpreter supports text-related tags and styles. Unsupported tags and styles are ignored.

This table lists the supported elements and element attributes.

HTML Element	Attributes	Description
`a`	`style`, `target`, `href`, `title`	Hyperlink
`abbr`	`style`, `title`	Abbreviation or acronym
`address`	`style`	Contact information
`article`	`style`	Self-contained, independent content
`aside`	`style`	Content indirectly related to the main content
`b`	`style`	Bold text
`bdi`	`style`, `dir`	Content formatted in a different direction from surrounding text
`bdo`	`style`, `dir`	Content formatted in a different direction from surrounding text
`big`	`style`	Text one font size level larger than surrounding text (obsolete in HTML5)
`blockquote`	`style`, `cite`	Extended quotation
`br`	n/a	Line break
`caption`	`style`	Caption or title of a table
`center`	`style`	Content centered horizontally
`cite`	`style`	Title of a creative work
`code`	`style`	Fragment of code
`col`	`style`, `align`, `valign`, `span`, `width`	Column within a table
`colgroup`	`style`, `align`, `valign`, `span`, `width`	Group of columns within a table
`dd`	`style`	Term or value in a description list
`del`	`style`, `datetime`	Text that was deleted from a document
`details`	`style`, `open`	Interactive widget with text visible only when toggled to 'open' state
`dl`	`style`	Description list
`dt`	`style`	Term or value in a description list
`em`	`style`	Emphasized text (typically displayed in italic)
`font`	`style`, `color`, `size`, `face`	Text with specified font properties (obsolete in HTML5)
`footer`	`style`	Footer
`h1`. `h2`, `h3`, `h4`, `h5`, `h6`	`style`	Section heading — `<h1>` is the highest level of heading and `<h6>` is the lowest
`header`	`style`	Introductory content
`hr`	`style`	Thematic break
`i`	`style`	Text offset from the surrounding content — by default rendered as italic
`ins`	`style`, `datetime`	Text inserted into a document
`li`	`style`	Item in a list
`mark`	`style`	Marked or highlighted text
`ol`	`style`	Ordered list
`p`	`style`	Paragraph
`pre`	`style`	Preformatted text
`s`	`style`	Text with a strikethrough
`strike`	`style`	Text with a strikethrough (obsolete in HTML5)
`section`	`style`	Standalone section
`small`	`style`	Text one font size level smaller than surrounding text (obsolete in HTML5)
`sub`	`style`	Subscript
`sup`	`style`	Superscript
`strong`	`style`	Text with strong importance
`table`	`style`, `width`, `border`, `align`, `valign`	Table
`tbody`	`style`, `align`, `valign`	Table body
`td`	`style`, `width`, `rowspan`, `colspan`, `align`, `valign`	Table data cell
`tfoot`	`style`, `align`, `valign`	Set of table rows that summarize the table columns
`th`	`style`, `width`, `rowspan`, `colspan`, `align`, `valign`	Table data cell specified as a header of a group of cells
`thead`	`style`, `align`, `valign`	Set of table rows that specify the column heads
`tr`	`style`, `rowspan`, `align`, `valign`	Row of table cells
`tt`	`style`	Monospace text (obsolete in HTML5)
`u`	`style`	Text with an unarticulated annotation — by default rendered as an underline
`ul`	`style`	Unordered list

For more information about these elements, see https://developer.mozilla.org/en-US/docs/Web/HTML/Element.

To use HTML markup to create a hyperlink that runs MATLAB code, see Create Hyperlinks that Run Functions.

You can use HTML style attributes to format HTML content. A style attribute is a string of CSS attributes and their values.

These CSS attributes are supported:

background-color
border-bottom
border-bottom-color
border-bottom-left-radius
border-bottom-right-radius
border-bottom-style
border-bottom-width
border-left
border-left-color
border-left-style
border-left-width
border-radius
border-right
border-right-color
border-right-style
border-right-width
border-spacing
border-style
border-top
border-top-color
border-top-left-radius
border-top-right-radius
border-top-style
border-top-width
border-width
color
direction
font-family
font-size
font-style
font-weight
height
hidden
line-height
margin
margin-bottom
margin-left
margin-right
margin-top
max-height
max-width
min-height
min-width
overflow
overflow-wrap
overflow-x
overflow-y
padding
padding-bottom
padding-left
padding-right
padding-top
text-align
text-anchor
text-decoration
text-indent
text-overflow
text-shadow
text-transform
title
translate
white-space
width

For more information about these attributes, see https://developer.mozilla.org/en-US/docs/Web/CSS/Reference.

Version History

Introduced in R2016a

expand all

R2021b: Style text and display equations

Use the Interpreter name-value argument to enable markup in the dialog box text. Specify the interpreter as 'html', 'latex', 'tex', or 'none'.

uialert

Syntax

Description

Examples

Alert App User to Error

Create Multiline Modal Alert Dialog Box with Warning Icon

Display Formatted MATLAB Error

Input Arguments

fig — Target figure Figure object

message — Message character vector | cell array of character vectors | string array

title — Title character vector | string scalar

Name-Value Arguments

CloseFcn — Alert dialog box close request function callback '' (default) | function handle | cell array | character vector

Icon — Icon 'error' (default) | predefined icon | custom icon