questdlg
Create question dialog box
If you are using App Designer or creating apps with the
uifigure function, then use uiconfirm instead. For more information, see GUIDE Migration Strategies.
Syntax
Description
answer = questdlg(quest)'Yes', 'No',
'Cancel', or ''.
By default, the dialog box has three standard buttons, labeled Yes, No, and Cancel.
If the user clicks one of these buttons, then the
answervalue is the same as the label of the pressed button.If the user clicks the close button (X) on the dialog box title bar or presses the Esc key, then the
answervalue is an empty character vector (' ').If the user presses the Return key, then the
answervalue is the same as the label of the default button selection. In this case,'Yes'.
answer = questdlg(quest,dlgtitle,btn1,btn2,defbtn)btn1 and btn2. The third standard
button is removed. The defbtn value must match the value of
btn1 or btn2.
If the user presses the keyboard Return key, and the
defbtn value does not match one of the button labels,
then the dialog box remains open.
Examples
Encode User's Choice as an Integer in Question Dialog Box
answer = questdlg('Would you like a dessert?', ... 'Dessert Menu', ... 'Ice cream','Cake','No thank you','No thank you'); % Handle response switch answer case 'Ice cream' disp([answer ' coming right up.']) dessert = 1; case 'Cake' disp([answer ' coming right up.']) dessert = 2; case 'No thank you' disp('I''ll bring you your check.') dessert = 0; end
To access the return value assigned to dessert, save
the example as a function. For example, create function
choosedessert by making this the first line of
code.
function dessert = choosedessert
Format Question in Dialog Box Using TeX
opts.Interpreter = 'tex'; % Include the desired Default answer opts.Default = 'Don''t know'; % Use the TeX interpreter to format the question quest = 'Is \Sigma(\alpha - \beta) < 0?'; answer = questdlg(quest,'Boundary Condition',... 'Yes','No','Don''t know',opts)
Input Arguments
quest — Dialog box question
character vector | cell array of character vectors | string array
Dialog box question, specified as a character vector, cell array of character vectors, or string array. The question automatically wraps to fit within the dialog box.
Example: 'What is the velocity?'
dlgtitle — Dialog box title
' ' (default) | character vector | string scalar
Dialog box title, specified as a character vector or string scalar.
Example: 'Configuration'
defbtn — Default button selection
character vector | string scalar
The default button selection, specified as a character vector or string
scalar. The default button selection is the value that MATLAB® returns if the user presses the keyboard
Return key instead of clicking a button in the dialog
box. The default selection must be the same as one of the dialog box button
labels. If the defbtn argument value does not match a
button label, then the dialog box remains open if the user presses the
keyboard Enter key.
Example: 'Cancel'
btn1 — First customized button label
character vector | string scalar
First customized button label, specified as a character vector or string scalar.
Example: 'Start'
btn2 — Second customized button label
character vector | string scalar
Second customized button label, specified as a character vector or string scalar.
Example: 'Reset'
btn3 — Third customized button label
character vector | string scalar
Third customized button label, specified as a character vector or string scalar.
Example: 'Test'
opts — Dialog box settings
structure
Dialog box settings specified as a structure. The structure specifies which button is the default button selection, and whether to use TeX to interpret the question text.
The opts structure, must include both of the fields
presented in this table. The structure can include additional fields, but
questdlg does not use them.
Field | Values |
|---|---|
| The default button selection, specified as a character vector or string scalar. The default selection must be the same as one of the dialog box button labels. The default button is the button value that MATLAB returns if the user presses the keyboard Return key instead of clicking a dialog box button. If the
|
|
Use TeX markup
to add superscripts and subscripts, modify the font
type and color, and include special characters in
the |
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{ | Font name — Replace
| '\fontname{Courier} text' |
\fontsize{ | Font size —Replace
| '\fontsize{15} text' |
\color{ | Font color — Replace
red, green,
yellow, magenta,
blue, black,
white, gray,
darkGreen, orange, or
lightBlue. | '\color{magenta} text' |
\color[rgb]{specifier} | Custom font color — Replace
| '\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 |
|---|---|---|---|---|---|
| α |
| υ |
| ~ |
| ∠ |
|
|
| ≤ |
|
|
| χ |
| ∞ |
| β |
| ψ |
| ♣ |
| γ |
| ω |
| ♦ |
| δ |
| Γ |
| ♥ |
| ϵ |
| Δ |
| ♠ |
| ζ |
| Θ |
| ↔ |
| η |
| Λ |
| ← |
| θ |
| Ξ |
| ⇐ |
| ϑ |
| Π |
| ↑ |
| ι |
| Σ |
| → |
| κ |
| ϒ |
| ⇒ |
| λ |
| Φ |
| ↓ |
| µ |
| Ψ |
| º |
| ν |
| Ω |
| ± |
| ξ |
| ∀ |
| ≥ |
| π |
| ∃ |
| ∝ |
| ρ |
| ∍ |
| ∂ |
| σ |
| ≅ |
| • |
| ς |
| ≈ |
| ÷ |
| τ |
| ℜ |
| ≠ |
| ≡ |
| ⊕ |
| ℵ |
| ℑ |
| ∪ |
| ℘ |
| ⊗ |
| ⊆ |
| ∅ |
| ∩ |
| ∈ |
| ⊇ |
| ⊃ |
| ⌈ |
| ⊂ |
| ∫ |
| · |
| ο |
| ⌋ |
| ¬ |
| ∇ |
| ⌊ |
| x |
| ... |
| ⊥ |
| √ |
| ´ |
| ∧ |
| ϖ |
| ∅ |
| ⌉ |
| 〉 |
| | |
| ∨ |
| 〈 |
| © |
Example:
opts.Default = 'Cancel'
Example:
opts.Interpreter = 'tex'