Panel Properties

Control panel appearance in uifigure-based apps

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Panels are containers for grouping together UI components. Properties control the appearance and behavior of a panel. Use dot notation to refer to a particular object and property.

fig = uifigure;
p = uipanel('Parent',fig);
p.Title = 'Display Options';

The properties listed here are valid for panels in App Designer, or in apps created with the uifigure function. For panels used in GUIDE, or in apps created with the figure function, see Panel Properties.

Title

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Title, specified as a character vector, string scalar, or categorical array. If you specify this property as a categorical array, MATLAB® displays only the first element in the array.

MATLAB does not interpret a vertical slash ('|') character as a line break, it displays as a vertical slash in the title.

If you want to specify a Unicode® character, pass the Unicode decimal code to the char function. For example, ['Multiples of ' char(960)] displays as Multiples of π.

Location of the title, specified as 'lefttop', 'centertop', or 'righttop'.

Color and Styling

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Title 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 NameShort NameRGB TripletHexadecimal Color CodeAppearance
'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 TripletHexadecimal Color CodeAppearance
[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'

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 NameShort NameRGB TripletHexadecimal Color CodeAppearance
'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 TripletHexadecimal Color CodeAppearance
[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'

Panel border, specified as 'line' or 'none'.

Font

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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:

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

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

Not all fonts have a bold font weight. Therefore, specifying a bold font weight can result in the normal font weight.

Font angle, specified as 'normal' or 'italic'. Setting this property to italic selects a slanted version of the font, if it is available on the app user’s system.

Font unit of measurement, specified as 'pixels'. Distances in pixels are independent of your system resolution on Windows® and Macintosh systems:

  • On Windows systems, a pixel is 1/96th of an inch.

  • On Macintosh systems, a pixel is 1/72nd of an inch.

  • On Linux® systems, the size of a pixel is determined by your system resolution.

Interactivity

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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 components that do not need to appear at startup.

Changing the size of an invisible container triggers the SizeChangedFcn callback when it becomes visible.

Changing the Visible property of a container does not change the values of the Visible properties of child components. This is true even though hiding the container causes the child components to be hidden.

Ability to scroll, 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.

Setting this property to 'on' enables scrolling within the container. However, there are additional requirements:

  • The child components in the container must occupy a larger area than the container can display at one time.

  • Components that do not fit in the container must be above or to the right of the container. You cannot scroll to components that are below or to the left of the container.

Certain types of charts and axes do not support scrollable containers. However, you can place the chart or axes in a nonscrollable panel, and then place the panel in the scrollable container. For more information, see Display Graphics in App Designer.

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.

  • If you set this property to 'on', the app user can interact with the component.

  • If you set this property to 'off', the component appears dimmed, indicating that the app user cannot interact with it, and that it will not trigger a callback.

Changing the value of the Enable property for a panel does not change the value of the Enable property for UI components contained within that panel.

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. 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.

Position

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Location and size of the panel, including borders and title, specified as a four-element vector of the form [left bottom width height]. This table describes each element in the vector.

ElementDescription
leftDistance from the inner left edge of the parent container to the outer left edge of the panel
bottomDistance from the inner bottom edge of the parent container to the outer bottom edge of the panel
widthDistance between the right and left outer edges of the panel
heightDistance between the top and bottom outer edges of the panel

All measurements are in units specified by the Units property.

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.

This property is read-only.

Location and size of the panel, excluding borders and title, returned as a four-element vector of the form [left bottom width height]. This table describes each element in the vector.

ValueDescription
leftDistance from the inner left edge of the parent container to the inner left edge of the panel.
bottomDistance from the inner bottom edge of the parent container to the inner bottom edge of the panel.
widthDistance between the inner edges of the panel’s right and left borders.
heightDistance between the inner edges of the panel’s top and bottom borders. This distance excludes the title, if it exists.

All measurements are in units specified by the Units property.

Note

These are some important points to consider when using the InnerPosition property:

  • InnerPosition values are affected by the presence (or absence) of a title, the font characteristics, and the BorderType.

  • InnerPosition values are relative to the parent container’s drawable area. The drawable area is the area inside the borders of the container and does not include the area occupied by the title.

Location and size of the panel, including borders and title, specified as a four-element vector of the form [left bottom width height]. All measurements are in units specified by the Units property.

This property value is identical to the Position property value.

Units of measurement, specified as 'pixels'.

Automatically resize children, 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' — Child components automatically resize when the container resizes.

  • 'off' — Child components do not resize.

The AutoResizeChildren property affects direct children of the container, not children inside nested containers.

To customize the resize behavior, set the AutoResizeChildren property to 'off' and create a SizeChangedFcn callback for the container. For more information, see Manage Resizable Apps in App Designer.

To disable resizing of an app, set the Resize property of the figure to 'off'.

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

g = uigridlayout([4 3]);
p = uipanel(g);
p.Layout.Row = 3;
p.Layout.Column = 2;

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

p.Layout.Column = [2 3];

Callbacks

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Size change 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.

Define this callback to customize the app layout when the size of this container changes (e.g., when the user resizes the window). In it, write code to adjust the Position property of the child components.

Note

The SizeChangedFcn callback will not execute unless the AutoResizeChildren property of this container is set to 'off'. In App Designer, you can make the SizeChangedFcn executable by selecting the container and clearing the AutoResizeChildren check box in the Inspector tab of the Component Browser.

The SizeChangedFcn callback executes when:

  • This container becomes visible for the first time.

  • This container is visible while its size changes.

  • This container becomes visible for the first time after its size changes. This situation occurs when the size changes while the container is invisible, and then it becomes visible later.

Other important points to consider when defining a SizeChangedFcn callback:

  • Consider delaying the display of this container until after all the variables that the SizeChangedFcn uses are defined. This practice can prevent the SizeChangedFcn callback from returning an error. To delay the display of the container, set its Visible property to 'off'. Then, set the Visible property to 'on' after you define the variables that your SizeChangedFcn callback uses.

  • If your app contains nested containers, they resize from the inside out.

  • To access the container that is resizing from within the SizeChangedFcn, refer to the source object (the first input argument in the callback) or use the gcbo function.

Alternate ways to specify resize behavior are to create a GridLayout object or use the auto-reflow options in App Designer. These options can be easier to use than SizeChangedFcn callbacks. However, there are some advantages that SizeChangedFcn callbacks have over these options. For example:

  • Resizing a component up to a minimum or maximum size that you define.

  • Implementing non-linear resize behaviors, like changing the size of a component based on the size of the parent container.

Button-press callback function, 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.

For more information about specifying a callback property value as a function handle, cell array, or character vector, see How to Specify Callback Property Values.

The ButtonDownFcn callback is a function that executes when the user clicks a mouse button within the container.

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 Write 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:

  • 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 Write 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

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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.

Whenever MATLAB invokes a callback, that callback attempts to interrupt the running callback (if one exists). The Interruptible property of the object owning the running callback determines if interruption is allowed.

  • A value of 'on' allows other callbacks to interrupt the object's callbacks. The interruption occurs at the next point where MATLAB processes the queue, such as when there is a drawnow, figure, uifigure, getframe, waitfor, or pause command.

    • If the running callback contains one of those commands, then MATLAB stops the execution of the callback at that point and executes the interrupting callback. MATLAB resumes executing the running callback when the interrupting callback completes.

    • If the running callback does not contain one of those commands, then MATLAB finishes executing the callback without interruption.

  • A value of 'off' blocks all interruption attempts. The BusyAction property of the object owning the interrupting callback determines if the interrupting callback is discarded or put into a queue.

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.

  • Timer objects execute according to schedule regardless of the Interruptible property value.

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.

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.

Whenever MATLAB invokes a callback, that callback attempts to interrupt a running callback. The Interruptible property of the object owning the running callback determines if interruption is permitted. If interruption is not permitted, then the BusyAction property of the object owning the interrupting callback determines if it is discarded or put in the queue. 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.

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

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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.

Panel child objects, returned as an empty GraphicsPlaceholder or a 1-D array of component objects. The children of a Panel can be any component object, including another Panel.

You cannot add or remove child components using the Children property. Use this property to view the list of children or to reorder the children. The order of the child objects in this array reflects the front-to-back stacking order of the components on the screen.

To add a child object to this list, set the Parent property of the child object to the Panel object.

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 ValueDescription
'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

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This property is read-only.

Type of graphics object, returned as 'uipanel'.

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.

See Also

Functions

Introduced in R2016a

MATLAB Documentation

Support