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Version: 4.16

RadioButton

Radio button with two states. A RadioButton is a button that changes appearance (state) when it has been pushed. Pushing the RadioButton again will return the to original state.

To make managing radio buttons much easier, they can be added to a RadioButtonGroup which then automates deselecting radio buttons when a new radio button is pressed.

See: RadioButtonGroup

Inherits from: AbstractButton, Widget, Drawable

Public Functions#

virtual voiddraw(const Rect & invalidatedArea) const
Draw this drawable.
voidexecuteDeselectedAction()
Executes the previously set action.
uint8_tgetAlpha() const
Gets the current alpha value, as previously set using setAlpha.
BitmapgetCurrentlyDisplayedBitmap() const
Gets currently displayed bitmap.
boolgetDeselectionEnabled() const
Gets the current deselectionEnabled state.
boolgetSelected() const
Gets the current selected state.
virtual RectgetSolidRect() const
Get (the largest possible) rectangle that is guaranteed to be solid (opaque).
virtual voidhandleClickEvent(const ClickEvent & event)
Updates the current state of the button.
RadioButton()
voidsetAlpha(uint8_t alpha)
Sets the alpha channel for the RadioButton, i.e.
virtual voidsetBitmaps(const Bitmap & bmpUnselected, const Bitmap & bmpUnselectedPressed, const Bitmap & bmpSelected, const Bitmap & bmpSelectedPressed)
Sets the four bitmaps used by this button.
voidsetDeselectedAction(GenericCallback< const AbstractButton & > & callback)
Associates an action to be performed when the RadioButton is deselected.
voidsetDeselectionEnabled(bool state)
Sets whether or not it is possible to deselect the RadioButton by clicking it.
voidsetSelected(bool newSelected)
Sets the radio buttons selected state.

Protected Attributes#

uint8_talpha
The current alpha value. 255=solid, 0=invisible.
BitmapbitmapSelected
The image to display when radio button selected and released.
BitmapbitmapSelectedPressed
The image to display when radio button selected and pressed.
BitmapbitmapUnselected
The image to display when radio button unselected and released.
BitmapbitmapUnselectedPressed
The image to display when radio button unselected and pressed.
GenericCallback< const AbstractButton & > *deselectedAction
The callback to be executed when this AbstractButton is deselected.
booldeselectionEnabled
Is it possible to deselect by pressing a selected RadioButton.
boolselected
The current selected state.

Additional inherited members#

Public Functions inherited from AbstractButton#

AbstractButton()
Sets this Widget touchable so the user can interact with buttons.
virtual voidexecuteAction()
Executes the previously set action.
virtual boolgetPressedState() const
Function to determine if the AbstractButton is currently pressed.
voidsetAction(GenericCallback< const AbstractButton & > & callback)
Associates an action with the button.

Protected Attributes inherited from AbstractButton#

GenericCallback< const AbstractButton & > *action
The callback to be executed when this AbstractButton is clicked.
boolpressed
Is the button pressed or released? True if pressed.

Public Functions inherited from Widget#

virtual voidgetLastChild(int16_t x, int16_t y, Drawable ** last)
Since a Widget is only one Drawable, Widget::getLastChild simply yields itself as result, but only if the Widget isVisible and isTouchable.

Public Functions inherited from Drawable#

virtual voidchildGeometryChanged()
This function can be called on parent nodes to signal that the size or position of one or more of its children has changed.
Drawable()
Initializes a new instance of the Drawable class.
voiddrawToDynamicBitmap(BitmapId id)
Render the Drawable object into a dynamic bitmap.
RectgetAbsoluteRect() const
Helper function for obtaining the rectangle this Drawable covers, expressed in absolute coordinates.
virtual Drawable *getFirstChild()
Function for obtaining the first child of this drawable if any.
int16_tgetHeight() const
Gets the height of this Drawable.
virtual voidgetLastChild(int16_t x, int16_t y, Drawable ** last) =0
Function for obtaining the the last child of this drawable that intersects with the specified point.
Drawable *getNextSibling()
Gets the next sibling node.
Drawable *getParent() const
Returns the parent node.
const Rect &getRect() const
Gets the rectangle this Drawable covers, in coordinates relative to its parent.
virtual RectgetSolidRectAbsolute()
Helper function for obtaining the largest solid rect (as implemented by getSolidRect()) expressed in absolute coordinates.
virtual voidgetVisibleRect(Rect & rect) const
Function for finding the visible part of this drawable.
int16_tgetWidth() const
Gets the width of this Drawable.
int16_tgetX() const
Gets the x coordinate of this Drawable, relative to its parent.
int16_tgetY() const
Gets the y coordinate of this Drawable, relative to its parent.
virtual voidhandleDragEvent(const DragEvent & evt)
Defines the event handler interface for DragEvents.
virtual voidhandleGestureEvent(const GestureEvent & evt)
Defines the event handler interface for GestureEvents.
virtual voidhandleTickEvent()
Called periodically by the framework if the Drawable instance has subscribed to timer ticks.
virtual voidinvalidate() const
Tell the framework that this entire Drawable needs to be redrawn.
virtual voidinvalidateRect(Rect & invalidatedArea) const
Request that a region of this drawable is redrawn.
boolisTouchable() const
Gets whether this Drawable receives touch events or not.
boolisVisible() const
Gets whether this Drawable is visible.
virtual voidmoveRelative(int16_t x, int16_t y)
Moves the drawable.
virtual voidmoveTo(int16_t x, int16_t y)
Moves the drawable.
virtual voidsetHeight(int16_t height)
Sets the height of this drawable.
voidsetPosition(const Drawable & drawable)
Sets the position of the Drawable to the same as the given Drawable.
voidsetPosition(int16_t x, int16_t y, int16_t width, int16_t height)
Sets the size and position of this Drawable, relative to its parent.
voidsetTouchable(bool touch)
Controls whether this Drawable receives touch events or not.
voidsetVisible(bool vis)
Controls whether this Drawable should be visible.
virtual voidsetWidth(int16_t width)
Sets the width of this drawable.
voidsetWidthHeight(const Bitmap & bitmap)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
voidsetWidthHeight(const Drawable & drawable)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
voidsetWidthHeight(const Rect & rect)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
voidsetWidthHeight(int16_t width, int16_t height)
Sets the dimensions (width and height) of the Drawable without changing the x and y coordinates).
virtual voidsetX(int16_t x)
Sets the x coordinate of this Drawable, relative to its parent.
voidsetXY(const Drawable & drawable)
Sets the x and y coordinates of this Drawable.
voidsetXY(int16_t x, int16_t y)
Sets the x and y coordinates of this Drawable, relative to its parent.
virtual voidsetY(int16_t y)
Sets the y coordinate of this Drawable, relative to its parent.
virtual voidtranslateRectToAbsolute(Rect & r) const
Helper function for converting a region of this Drawable to absolute coordinates.
virtual ~Drawable()
Finalizes an instance of the Drawable class.

Protected Attributes inherited from Drawable#

Drawable *nextSibling
Pointer to the next Drawable.
Drawable *parent
Pointer to this drawable's parent.
Rectrect
The coordinates of this Drawable, relative to its parent.
booltouchable
True if this drawable should receive touch events.
boolvisible
True if this drawable should be drawn.

Public Functions Documentation#

draw#

virtual void draw(const Rect &invalidatedArea)

Draw this drawable.

It is a requirement that the draw implementation does not draw outside the region specified by invalidatedArea.

Parameters:
invalidatedAreaThe sub-region of this drawable that needs to be redrawn, expressed in coordinates relative to its parent (e.g. for a complete redraw, invalidatedArea will be (0, 0, width, height).

Reimplements: touchgfx::Drawable::draw

executeDeselectedAction#

Executes the previously set action.

See also:

getAlpha#

uint8_t getAlpha()const

Gets the current alpha value, as previously set using setAlpha.

The default alpha value (if the alpha value has not been changed using setAlpha) is 255=solid.

Returns:

The current alpha value ranging from 255=solid to 0=invisible.

See also:

getCurrentlyDisplayedBitmap#

Gets currently displayed bitmap.

This depends on whether the RadioButton is currently selected or not and whether it is being pressed or not, i.e. it depends on the radio button's pressed and selected state.

Returns:

The bitmap currently displayed.

getDeselectionEnabled#

Gets the current deselectionEnabled state.

Returns:

The current deselectionEnabled state.

See also:

getSelected#

bool getSelected()const

Gets the current selected state.

Returns:

The current selected state.

getSolidRect#

virtual Rect getSolidRect()const

Get (the largest possible) rectangle that is guaranteed to be solid (opaque).

This information is important, as any Drawable underneath the solid area does not need to be drawn.

Returns:

The solid rectangle part of the Drawable.

Note

The rectangle returned must be relative to upper left corner of the Drawable, meaning that a completely solid widget should return the full size Rect(0, 0, getWidth(), getHeight()). If no area can be guaranteed to be solid, an empty Rect(0, 0, 0, 0) must be returned. Failing to return the correct rectangle may result in errors on the display.

Reimplements: touchgfx::Drawable::getSolidRect

handleClickEvent#

virtual void handleClickEvent(const ClickEvent &event)

Updates the current state of the button.

The state can be either pressed or released, and if the new state is different from the current state, the button is also invalidated to force a redraw.

If the button state is changed from ClickEvent::PRESSED to ClickEvent::RELEASED, the associated action (if any) is also executed.

Parameters:
eventInformation about the click.

Reimplements: touchgfx::AbstractButton::handleClickEvent

RadioButton#

setAlpha#

void setAlpha(uint8_talpha)

Sets the alpha channel for the RadioButton, i.e.

all the images used. The default alpha value on a RadioButton is 255.

Parameters:
alphaThe alpha value ranging from 255=solid to 0=invisible.
See also:

setBitmaps#

virtual void setBitmaps(const Bitmap &bmpUnselected ,
const Bitmap &bmpUnselectedPressed ,
const Bitmap &bmpSelected ,
const Bitmap &bmpSelectedPressed
)

Sets the four bitmaps used by this button.

The first two bitmaps must show the unselected Button when it is released and pressed. The last two bitmaps must show the selected Button when it is released and pressed.

Parameters:
bmpUnselectedBitmap to use when button is unselected and released.
bmpUnselectedPressedBitmap to use when button is unselected and pressed.
bmpSelectedBitmap to use when button is selected and released.
bmpSelectedPressedBitmap to use when button is selected and pressed.
Note

It is not uncommon to have the same bitmap for released (normal) and pressed state.

setDeselectedAction#

Associates an action to be performed when the RadioButton is deselected.

Parameters:
callbackThe callback to be executed. The callback will be given a reference to the AbstractButton.
Note

The action performed when the RadioButton is selected, is set using setAction().

setDeselectionEnabled#

void setDeselectionEnabled(boolstate)

Sets whether or not it is possible to deselect the RadioButton by clicking it.

By default it is not possible to deselect a RadioButton. The meaning of this is most clear when the RadioButton is used in a RadioButtonGroup where exactly one RadioButton should always be selected. Pressing the currently selected RadioButton should not deselect it, but rather select it again. This makes the button "sticky", i.e. a button can only be deselected by selecting another RadioButton in the same RadioButtonGroup.

Parameters:
statetrue if it should be possible to deselect by click. Default is false.
See also:

setSelected#

void setSelected(boolnewSelected)

Sets the radio buttons selected state.

Note that the associated action is also performed.

Parameters:
newSelectedThe new selected state.
Note

If the RadioButton is part of a RadioButtonGroup, setting the selected state of individual RadioButtons is not recommended.

See also:

Protected Attributes Documentation#

alpha#

uint8_t alpha

The current alpha value. 255=solid, 0=invisible.

bitmapSelected#

Bitmap bitmapSelected

The image to display when radio button selected and released.

bitmapSelectedPressed#

Bitmap bitmapSelectedPressed

The image to display when radio button selected and pressed.

bitmapUnselected#

Bitmap bitmapUnselected

The image to display when radio button unselected and released.

bitmapUnselectedPressed#

Bitmap bitmapUnselectedPressed

The image to display when radio button unselected and pressed.

deselectedAction#

GenericCallback< const AbstractButton & > * deselectedAction

The callback to be executed when this AbstractButton is deselected.

deselectionEnabled#

bool deselectionEnabled

Is it possible to deselect by pressing a selected RadioButton.

selected#

bool selected

The current selected state.