lvppLabel Class Reference

Enable the display of a text item. More...

#include <lvpp.h>

Inheritance diagram for lvppLabel:

Collaboration diagram for lvppLabel:

Public Member Functions
	lvppLabel (const char *fName, const char *pText=nullptr, lv_obj_t *parent=nullptr)
	Construct a new lvpp Label object.
virtual void	setText (const char *pText)
	Set the Text value to display.
void	setTextColor (lv_color_t newColor)
	Set the Text Color of the label (not the background)
Public Member Functions inherited from lvppBase
	lvppBase (const char *fName, const char *oType)
	Construct a new lvpp Base object.
	~lvppBase ()
void	createObj (lv_obj_t *o)
	Create the handlers and store the newly created object.
lv_obj_t *	getObj (void)
	Get the Obj object.
lv_obj_t *	getLabelObj (void)
	Get the label object.
virtual void	setSize (lv_coord_t width, lv_coord_t height)
	Set the Size object. Most of the time, LVGL does a great job of setting a sane size, but manipulation of things like the text or the font size can cause this to no longer be a good size. It is a common use pattern to instantiate a widget and then use setSize() and align() to place them in your user interface as needed.
void	align (lv_align_t align, lv_coord_t x_ofs, lv_coord_t y_ofs)
	Change the x/y location of the object.
void	setFontSize (uint8_t points)
	Set the Font Size for the object in simple 'points'.
void	setFont (const lv_font_t *pF)
	Set the Font to be used. This is a more complete/complex version of setFontSize(). The fact that the font pointer is required at least means the user knows the font exists.
void	setBGColor (lv_color_t color)
	Set the background color of the object.
void	setColorGradient (lv_color_t col1, lv_color_t col2, lv_grad_dir_t direction)
	Sets a Color Gradient from col1 to col2 in a vertical or horizontal direction. The gradient is place on the indicator for lvppBar, lvppSlider, and lvppArc. The graident is placed on the 'main' area of all other objects.
virtual void	setText (const char *pText)
	Set the Text for the primary text label. For a button, for instance, this is the text on top of the button.
std::string	getText ()
	Get the Text from the object/label and put it in a std::string.
void	setTextAlign (lv_align_t align, lv_coord_t xoff, lv_coord_t yoff)
	Set the Text Alignment. This allows the object's primary label to be moved from its 'center' position.
void	setTextColor (lv_color_t newColor)
	Set the Text Color of the primary label object.
void	setLabelJustificationAlignment (lv_text_align_t _align)
	Set the Label's text alignment (left/right/center)
void	setLabelColorizationEnabled (bool bEnable=true)
	Turn on or off inline text colorization. To use colors inline, simply use #RRGGBB in the text where the R, G, and B are hex values. Be sure to have a space before and after.
virtual void	setAdjText (const char *pText, lv_coord_t x_ofs=-10000, lv_coord_t y_ofs=-10000)
	Set the text for the adjacent text label. This label is not enabled by default. Setting this text will create and enable the adjacent label object. The label's position can be set, optionally, as well.
void	setAdjTextColor (lv_color_t newColor)
	Set the Adjacent text color.
void	setAdjBGColor (lv_color_t color)
	set the background color for the adjacent text
void	setAdjColorGradient (lv_color_t col1, lv_color_t col2, lv_grad_dir_t direction)
	Sets a Color Gradient from col1 to col2 in a vertical or horizontal direction.
void	setAdjFont (const lv_font_t *pF)
	Set the Font to be used for the adjacent text.
void	setAdjJustificationAlignment (lv_text_align_t _align)
	Set the adjacent Label's text alignment (left/right/center)
virtual void	onClicked ()
	Callback that derived objects can use to get notification when the object is clicked.
virtual void	internalOnClicked ()
	Internal version of the onClicked() callback which is used for other derived internal objects in the library.
virtual void	onValueChanged ()
	Callback that derived objects can use to get notification when the value changes of an object.
virtual void	internalOnValueChanged ()
	Internal version of the onValueChanged() callback which is used for other derived internal objects in the library.
void	setFriendlyName (const char *pName)
	Set the Friendly Name of the object. This is the name given in the constructor's fName parameter and is unlikely to be changed. However, it can be via this method.
std::string	getFriendlyName ()
	Get the Friendly Name of the object.
std::string	getObjType ()
	Get the Obj Type.
const char *	whoAmI (void)
	Utility useful for dumping the friendly name and object type if needed.
void	setCallbackOnClicked (std::function< void()> cbF)
	Uses a lambda callback for when an object is clicked.
void	setCallbackOnValueChanged (std::function< void()> cbF)
	Uses a lambda callback for when an object value changes.
virtual void	setNewParent (lv_obj_t *pNewParent)
	Changes the parent object on the fly. Used primarily for lvppScreen::addObject(). Sets parents of adjacent label, value label, and label appropriately.

Additional Inherited Members
Static Public Member Functions inherited from lvppBase
static const char *	getEventName (lv_event_code_t code)
	Get the Event Name from a given event code. Translate it to text, essentially.
static bool	isUnknownCode (lv_event_code_t code)
	Check to see if an event code is valid or not. Utility function.
Protected Member Functions inherited from lvppBase
void	setObjType (const char *pType)
void	baseEventHandler (lv_event_t *event)
	Main event handler loop for all events. This handler makes calls for onClicked() and onValueChanged()
virtual void	eventHandler (lv_event_t *event)
	Any events not handled by baseEventHandler come here. Can be overridden by a derived class.
Static Protected Member Functions inherited from lvppBase
static void	lvCallback (lv_event_t *event)
	Static member to handle all inbound callback events. Used to "route" event handling to the appropriate C++ object.
static void	initEventNames (void)
	One-time initialization of the event names array.
Protected Attributes inherited from lvppBase
lv_obj_t *	label
	Primary label.
lv_obj_t *	adjLabel
	For items that have a label 'nearby' (adjacent label)
std::function< void()>	cbOnClicked =nullptr
	Start without a lambda callback.
std::function< void()>	cbOnValueChanged =nullptr
	Start without a lambda callback.
lv_obj_t *	obj
	The LVGL object that was created for this widget.
lv_obj_t *	objParent
	Any parent object (following same principle as LVGL here)
std::string	objType
std::string	friendlyName
lv_style_t	style_obj
	Main style object - unsure if I'm handling all of the style bit correctly.
Static Protected Attributes inherited from lvppBase
static bool	bEventNamesInitComplete = false
	Status of the event names table to avoid re-processing.

Detailed Description

Enable the display of a text item.

Constructor & Destructor Documentation

lvppLabel()

lvppLabel::lvppLabel	(	const char *	fName,
		const char *	pText = nullptr,
		lv_obj_t *	parent = nullptr
	)

Construct a new lvpp Label object.

Parameters

fName	Internal object name. This is generally used in findObj() or lvppScreen
pText	Starting text for the label. Can be changed subsequently. Default nullptr.
parent	If provided, the parent of the object. This is a real LVGL lv_obj_t pointer

Special case - this is a label object, so the label object has a 'label' which is itself... this is primarily about getLabelObj() doing the 'smart thing'.

Member Function Documentation

setText()

void lvppLabel::setText ( const char *  pText )

virtual

Set the Text value to display.

Parameters

pText

pointer to a char string for the new value/contents of the label.

Reimplemented from lvppBase.

setTextColor()

void lvppLabel::setTextColor

(

lv_color_t

newColor

)

Set the Text Color of the label (not the background)

Parameters

newColor

This is the new color to be used for the label. It is an LVGL lv_color_t construct. Examples would be lv_color_black() or lv_palette_main(LV_COLOR_BLUE) or custom created colors.

Todo:

I think this add_style needs to go away and an 'invalidate' should be used instead.

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The documentation for this class was generated from the following files:

• src/lvpp.h
• src/lvppLabel.cpp