Transform Properties

Control transform appearance and behavior

Transform properties control the behavior of transform objects. By changing property values, you can modify certain aspects of the transform object. Use dot notation to refer to a particular object and property:

h = hgtransform;
c = h.Children;
h.Matrix = makehgtform('scale',0.5);

Transform Matrix

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MatrixTransform matrix4-by-4 matrix

Transform matrix applied to the transform object and its children, specified as a 4-by-4 matrix. For more information about defining this matrix, see Transforms Supported by hgtransform.

Data Types: double

Visibility

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VisibleVisibility of transform'on' (default) | 'off'

Visibility of transform, specified as one of these values:

  • 'on' — Display all objects in the transform.

  • 'off' — Hide all objects in the transform. You still can access the properties of invisible transform objects. Setting the Visible property for the transform object does not change the Visible property for objects in the transform.

EraseMode(removed) Technique to draw and erase objects'normal' (default) | 'none' | 'xor' | 'background'

    Note:   EraseMode has been removed. You can delete code that accesses the EraseMode property with minimal impact. If you were using EraseMode to create line animations, use the animatedline function instead.

Technique to draw and erase objects, specified as one of these values:

  • 'normal' — Redraw the affected region of the display, performing the three-dimensional analysis necessary to correctly render all objects. This mode produces the most accurate picture, but is the slowest. The other modes are faster, but do not perform a complete redraw and, therefore, are less accurate.

  • 'none' — Do not erase the object when it is moved or destroyed. After you erase the object with EraseMode,'none', it is still visible on the screen. However, you cannot print the object because MATLAB® does not store any information on its former location.

  • 'xor' — Draw and erase the object by performing an exclusive OR (XOR) with the color of the screen beneath it. This mode does not damage the color of the objects beneath it. However, the object color depends on the color of whatever is beneath it on the display.

  • 'background' — Erase the object by redrawing it in the axes background color, or the figure background color if the axes Color property is 'none'. This damages objects that are behind the erased object, but properly colors the erased object.

MATLAB always prints figures as if the EraseMode property of all objects is set to 'normal'. This means graphics objects created with EraseMode set to 'none', 'xor', or 'background' can look different on screen than on paper. On screen, MATLAB mathematically combines layers of colors and ignores three-dimensional sorting to obtain greater rendering speed. However, MATLAB does not apply these techniques to the printed output. Use the getframe command or other screen capture applications to create an image of a figure containing nonnormal mode objects.

Identifiers

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TypeType of graphics object'hgtransform'

This property is read only.

Type of graphics object, returned as 'hgtransform'. Use this property to find all objects of a given type within a plotting hierarchy, for example, searching for the type using findobj.

TagTag to associate with transform'' (default) | string

Tag to associate with the transform, specified as a string. Tags provide a way to identify graphics objects. Use this property to find all objects with a specific tag within a plotting hierarchy, for example, searching for the tag using findobj.

Example: 'January Data'

UserDataData to associate with transform[] (default) | scalar, vector, or matrix | cell array | character array | table | structure

Data to associate with the transform object, specified as a scalar, vector, matrix, cell array, character array, table, or structure. MATLAB does not use this data.

To associate multiple sets of data or to attach a field name to the data, use the getappdata and setappdata functions.

Example: 1:100

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | char | struct | table | cell

DisplayNameText used by legend'' (default) | string

Text used by the legend, specified as a string. The text appears next to an icon of the transform.

  • If you specify text for the transform object as an input argument to the legend function, then the legend uses the specified text and updates the DisplayName.

  • If you do not specify text for the transform object as an input argument to the legend function, then the legend uses the text in the DisplayName property. If the DisplayName property does not contain any text, then the legend generates a string. The string has the form 'dataN', where N is the number assigned to the transform object based on its location in the list of legend entries.

If you edit interactively the string in an existing legend, then MATLAB updates the DisplayName to the edited string.

Example: 'Text Description'

AnnotationLegend icon display styleAnnotation object

This property is read only.

Legend icon display style, returned as an Annotation object. Use this object to include or exclude the transform from a legend.

  1. Query the Annotation property to get the Annotation object.

  2. Query the LegendInformation property of the Annotation object to get the LegendEntry object.

  3. Specify the IconDisplayStyle property of the LegendEntry object to one of these values:

    • 'on' — Include the transform object in the legend as one entry (default).

    • 'off' — Do not include the transform object in the legend.

    • 'children' — Include only children of the transform object as separate entries in the legend.

If a legend already exists and you change the IconDisplayStyle setting, then you must call legend to update the display.

Parent/Child

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ParentParent of transformaxes object | group object | transform object

Parent of transform, specified as an axes, group, or transform object.

ChildrenChildren of transformempty GraphicsPlaceholder array | array of graphics objects

Children of transform, returned as an array of graphics objects. Use this property to view a list of the children or to reorder the children by setting the property to a permutation of itself.

You cannot add or remove children using the Children property of the transform. To add a child to this list, set the Parent property of the child graphics object to the transform object.

HandleVisibilityVisibility of object handle'on' (default) | 'off' | 'callback'

Visibility of object handle in the Children property of the parent, specified as one of these values:

  • 'on' — List the transform object.

  • 'off' — Do not list the transform object. Use this option to hide object handles when a callback invokes a function that could damage the GUI, such as evaluating a user-typed string.

  • 'callback' — List the transform object in the Children property of the parent from within callbacks or functions invoked by callbacks, but not from within functions invoked from the command line. Use this option to protect a GUI from command-line users, while allowing callbacks to have access to objects.

If the transform object is not listed in the Children property of the parent, then functions that obtain object handles by searching the object hierarchy or querying handle properties cannot return it. This includes get, findobj, gca, gcf, gco, newplot, cla, clf, and close.

Hidden object handles are still valid. Set the root ShowHiddenHandles property to 'on' to list all object handles regardless of their HandleVisibility property setting.

Interactive Control

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ButtonDownFcnMouse-click callback'' (default) | function handle | cell array | string

Mouse-click callback, specified as one of these values:

  • Function handle

  • Cell array containing a function handle and additional arguments

  • String that is a valid MATLAB command or function, which is evaluated in the base workspace (not recommended)

Use this property to execute code when you click the transform. If you specify this property using a function handle, then MATLAB passes two arguments to the callback function when executing the callback:

  • The transform object — You can access properties of the transform object from within the callback function.

  • Event data — This argument is empty for this property. Replace it with the tilde character (~) in the function definition to indicate that this argument is not used.

For more information on how to use function handles to define callback functions, see Callback Definition.

    Note:   If the PickableParts property is set to 'none' or if the HitTest property is set to 'off', then this callback does not execute.

Example: @myCallback

Example: {@myCallback,arg3}

UIContextMenuContext menuuicontextmenu object

Context menu, specified as a uicontextmenu object. Use this property to display a context menu when you right-click the transform. Create the context menu using the uicontextmenu function.

    Note:   If the PickableParts property is set to 'none' or if the HitTest property is set to 'off', then the context menu does not appear.

SelectedSelection state'off' (default) | 'on'

Selection state, specified as one of these values:

  • 'on' — Selected. If you click the transform when in plot edit mode, then MATLAB sets its Selected property to 'on'. If the SelectionHighlight property also is set to 'on', then MATLAB displays selection handles around the transform.

  • 'off' — Not selected.

SelectionHighlightDisplay of selection handles when selected'on' (default) | 'off'

Display of selection handles when selected, specified as one of these values:

  • 'on' — Display selection handles when the Selected property is set to 'on'.

  • 'off' — Never display selection handles, even when the Selected property is set to 'on'.

Callback Execution Control

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PickablePartsChildren that can capture mouse clicks'visible' (default) | 'none'

Children that can capture mouse clicks, specified as one of these values:

  • 'visible' — Any child object can capture a mouse click, depending on the PickableParts property value of the child.

  • 'none' — No child objects can capture mouse clicks, regardless of the PickableParts property value of the child.

HitTestResponse to mouse clicks captured by children'on' (default) | 'off'

Response to mouse clicks captured by children, specified one of these values:

  • 'on' — Trigger the ButtonDownFcn callback of transform. If you have defined the UIContextMenu property, then invoke the context menu.

  • 'off' — Do not trigger the callbacks of the transform. Instead, trigger the callbacks for the nearest ancestor of the transform that has a HitTest property set to 'on' and a PickableParts property value that enables the ancestor to capture mouse clicks.

A transform cannot capture mouse clicks. However, if you click a child of the transform and if the child has a HitTest property set to 'off', then the child passes the click to the transform.

InterruptibleCallback interruption'on' (default) | 'off'

Callback interruption, specified as 'on' or 'off'. The Interruptible property determines if a running callback can be interrupted.

    Note:   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 allowed. If interruption is not allowed, then the BusyAction property of the object owning the interrupting callback determines if it is discarded or put in the queue.

If the ButtonDownFcn callback of the transform is the running callback, then the Interruptible property determines if it another callback can interrupt it:

  • 'on' — Interruptible. Interruption occurs at the next point where MATLAB processes the queue, such as when there is a drawnow, figure, getframe, waitfor, or pause command.

    • If the running callback contains one of these commands, then MATLAB stops the execution of the callback at this point and executes the interrupting callback. MATLAB resumes executing the running callback when the interrupting callback completes. For more information, see Interrupt Callback Execution.

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

  • 'off' — Not interruptible. MATLAB finishes executing the running callback without any interruptions.

BusyActionCallback queuing'queue' (default) | 'cancel'

Callback queuing specified as 'queue' or 'cancel'. The BusyAction property determines how MATLAB handles the execution of interrupting callbacks.

    Note:   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 allowed. If interruption is not allowed, then the BusyAction property of the object owning the interrupting callback determines if it is discarded or put in the queue.

If the ButtonDownFcn callback of the transform tries to interrupt a running callback that cannot be interrupted, then the BusyAction property determines if it is discarded or put in the queue. Specify the BusyAction property as one of these values:

  • 'queue' — Put the interrupting callback in a queue to be processed after the running callback finishes execution. This is the default behavior.

  • 'cancel' — Discard the interrupting callback.

Creation and Deletion Control

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CreateFcnCreation callback'' (default) | function handle | cell array | string

Creation callback, specified as one of these values:

  • Function handle

  • Cell array containing a function handle and additional arguments

  • String that is a valid MATLAB command or function, which is evaluated in the base workspace (not recommended)

Use this property to execute code when you create the transform. Setting the CreateFcn property on an existing transform has no effect. You must define a default value for this property, or define this property using a Name,Value pair during transform creation. MATLAB executes the callback after creating the transform and setting all of its properties.

If you specify this callback using a function handle, then MATLAB passes two arguments to the callback function when executing the callback:

  • The transform object — You can access properties of the transform object from within the callback function. You also can access the transform object through the CallbackObject property of the root, which can be queried using the gcbo function.

  • Event data — This argument is empty for this property. Replace it with the tilde character (~) in the function definition to indicate that this argument is not used.

For more information on how to use function handles to define callback functions, see Callback Definition.

Example: @myCallback

Example: {@myCallback,arg3}

DeleteFcnDeletion callback'' (default) | function handle | cell array | string

Deletion callback, specified as one of these values:

  • Function handle

  • Cell array containing a function handle and additional arguments

  • String that is a valid MATLAB command or function, which is evaluated in the base workspace (not recommended)

Use this property to execute code when you delete the transform. MATLAB executes the callback before destroying the transform so that the callback can access its property values.

If you specify this callback using a function handle, then MATLAB passes two arguments to the callback function when executing the callback:

  • The transform object — You can access properties of the transform object from within the callback function. You also can access the transform object through the CallbackObject property of the root, which can be queried using the gcbo function.

  • Event data — This argument is empty for this property. Replace it with the tilde character (~) in the function definition to indicate that this argument is not used.

For more information on how to use function handles to define callback functions, see Callback Definition.

Example: @myCallback

Example: {@myCallback,arg3}

BeingDeletedDeletion status of transform'off' (default) | 'on'

This property is read only.

Deletion status of transform, returned as 'on' or 'off'. MATLAB sets the BeingDeleted property to 'on' when the delete function of the transform begins execution (see the DeleteFcn property). The BeingDeleted property remains set to 'on' until the transform no longer exists.

Check the value of the BeingDeleted property to verify that the transform is not about to be deleted before querying or modifying it.

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