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Lamp Properties

Control lamp appearance

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Lamps are app components that indicate state using color. Properties control the appearance and behavior of a lamp. Use dot notation to refer to a specific object and property.

fig = uifigure; mylamp = uilamp(fig); mylamp.Color = 'red';

Color

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Color of the lamp, 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 from0toF. 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'

Sample of the color red
'green' 'g' [0 1 0] '#00FF00'

Sample of the color green
'blue' 'b' [0 0 1] '#0000FF'

Sample of the color blue
'cyan' 'c' [0 1 1] '#00FFFF'

Sample of the color cyan
'magenta' 'm' [1 0 1] '#FF00FF'

Sample of the color magenta
'yellow' 'y' [1 1 0] '#FFFF00'

Sample of the color yellow
'black' 'k' [0 0 0] '#000000'

Sample of the color black
'white' 'w' [1 1 1] '#FFFFFF'

Sample of the color white

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'

Sample of RGB triplet [0 0.4470 0.7410], which appears as dark blue
[0.8500 0.3250 0.0980] '#D95319'

Sample of RGB triplet [0.8500 0.3250 0.0980], which appears as dark orange
[0.9290 0.6940 0.1250] '#EDB120'

Sample of RGB triplet [0.9290 0.6940 0.1250], which appears as dark yellow
[0.4940 0.1840 0.5560] '#7E2F8E'

Sample of RGB triplet [0.4940 0.1840 0.5560], which appears as dark purple
[0.4660 0.6740 0.1880] '#77AC30'

Sample of RGB triplet [0.4660 0.6740 0.1880], which appears as medium green
[0.3010 0.7450 0.9330] '#4DBEEE'

Sample of RGB triplet [0.3010 0.7450 0.9330], which appears as light blue
[0.6350 0.0780 0.1840] '#A2142F'

Sample of RGB triplet [0.6350 0.0780 0.1840], which appears as dark red

Data Types:double|char

Interactivity

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State of visibility, specified as'on'or'off', or as numeric or logical1(true) or0(false). A value of'on'相当于true, and'off'相当于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 typematlab.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 theVisibleproperty to'off'for all UI components that do not need to appear at startup.

Operational state of the lamp, specified as'on'or'off'.

  • If you set this property to'on', then the lamp appears bright, indicating that the lamp is operational.

  • If you set this property to'off', then the lamp appears dimmed.

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 aContextMenuobject created using theuicontextmenufunction. 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 lamp, 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 lamp
bottom Distance from the inner bottom edge of the parent container to the outer bottom edge of the lamp
width Distance between the right and left outer edges of the lamp
height Distance between the top and bottom outer edges of the lamp

All measurements are in pixel units.

Due to aspect ratio constraints, you cannot change the lamp height and width independently of one another.

ThePositionvalues are relative to thedrawable areaof 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:[100 200 20 20]

Inner location and size of the lamp, 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 thePositionproperty.

This property is read-only.

Outer location and size of the lamp, 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 thePositionproperty.

Layout options, specified as aGridLayoutOptionsobject. 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 theRowandColumnproperties on theGridLayoutOptionsobject.

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

g = uigridlayout([4 3]); mylamp = uilamp(g); mylamp.Layout.Row = 3; mylamp.Layout.Column = 2;

To make the lamp span multiple rows or columns, specify theRoworColumnproperty as a two-element vector. For example, this lamp spans columns2through3:

mylamp.Layout.Column = [2 3];

Callbacks

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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, seeWrite Callbacks in App Designer.

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

Setting theCreateFcnproperty 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 thegcbofunction 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, seeWrite Callbacks in App Designer.

This property specifies a callback function to execute when MATLAB deletes the object. MATLAB executes theDeleteFcncallback before destroying the properties of the object. If you do not specify theDeleteFcnproperty, 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 thegcbofunction to access the object.

Callback Execution Control

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Callback interruption, specified as'on'or'off', or as numeric or logical1(true) or0(false). A value of'on'相当于true, and'off'相当于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 typematlab.lang.OnOffSwitchState.

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

  • Therunningcallback is the currently executing callback.

  • Theinterruptingcallback 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 includedrawnow,figure,uifigure,getframe,waitfor, andpause.

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 theInterruptibleproperty of the object that owns the running callback determines if the interruption occurs:

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

  • If the value ofInterruptibleis'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 aDeleteFcn,CloseRequestFcn, orSizeChangedFcn回调,那么无论发生中断of theInterruptibleproperty value.

  • If the running callback is currently executing thewaitforfunction, then the interruption occurs regardless of theInterruptibleproperty value.

  • If the interrupting callback is owned by aTimerobject, then the callback executes according to schedule regardless of theInterruptibleproperty value.

Note

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

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

  • Therunningcallback is the currently executing callback.

  • Theinterruptingcallback is a callback that tries to interrupt the running callback.

TheBusyActionproperty determines callback queuing behavior only when both of these conditions are met:

  • 过程的运行调包含一个命令sses the callback queue, such asdrawnow,figure,uifigure,getframe,waitfor, orpause.

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

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

  • '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 typematlab.lang.OnOffSwitchState.

MATLAB sets theBeingDeletedproperty to'on'when theDeleteFcncallback begins execution. TheBeingDeletedproperty remains set to'on'until the component object no longer exists.

Check the value of theBeingDeleted属性来验证object is not about to be deleted before querying or modifying it.

Parent/Child

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Parent container, specified as aFigureobject created using theuifigurefunction, or one of its child containers:Tab,Panel,ButtonGroup, orGridLayout. If no container is specified, MATLAB calls theuifigurefunction to create a newFigureobject 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 includeget,findobj,clf, andclose. 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 theHandleVisibilityto'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'uilamp'.

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

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.

如果你是工作在应用程序设计师,创造公众or private properties in the app to share data instead of using theUserDataproperty. For more information, seeShare Data Within App Designer Apps.

See Also

Functions

Introduced in R2016a

MATLAB Documentation

金宝app

Introducing Deep Learning with MATLAB

Introducing Deep Learning with MATLAB

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