gp_widget_ops.h File Reference

Widget internals. More...

#include <input/gp_event.h>
#include <utils/gp_bbox.h>
#include <utils/gp_json.h>
#include <widgets/gp_widget.h>
#include <widgets/gp_widget_render.h>

Go to the source code of this file.

Data Structures
struct	gp_widget_ops
	Callbacks that implements a widget. More...

Enumerations
enum	gp_widget_focus_flag {   GP_FOCUS_OUT , GP_FOCUS_IN , GP_FOCUS_LEFT , GP_FOCUS_RIGHT ,   GP_FOCUS_UP , GP_FOCUS_DOWN , GP_FOCUS_NEXT , GP_FOCUS_PREV }
	Flags to move focus around. More...
enum	gp_widget_render_flags { GP_WIDGET_REDRAW = 0x01 , GP_WIDGET_REDRAW_CHILDREN = 0x02 , GP_WIDGET_COLOR_SCHEME = 0x04 , GP_WIDGET_RESIZE = 0x08 , GP_WIDGET_DISABLED = 0x10 }
	Widget rendering flags. More...

Functions
int	gp_widget_ops_event (gp_widget *self, const gp_widget_render_ctx *ctx, gp_event *ev)
	Send an event to a widget.
int	gp_widget_ops_render_focus (gp_widget *self, int focus_dir)
	Moves focus, if possible, in the direction requested by the focus_dir.
int	gp_widget_ops_render_focus_xy (gp_widget *self, const gp_widget_render_ctx *ctx, unsigned int x, unsigned int y)
	Tries to focus a widget on a given coordinates in a layout.
int	gp_widget_ops_focus_widget (gp_widget *self)
	Moves focus to a particular widget.
void	gp_widget_ops_for_each_child (gp_widget *self, void(*func)(gp_widget *child))
	Calls a callback on each child widget.
static void	gp_widget_ops_blit (const gp_widget_render_ctx *ctx, gp_coord x, gp_coord y, gp_size w, gp_size h)
	Marks an area to be blit on the screen from a buffer.
static int	gp_widget_should_redraw (gp_widget *self, int flags)
	Returns true if widget should be repainted.
void	gp_widget_calc_size (gp_widget *layout, const gp_widget_render_ctx *ctx, unsigned int w, unsigned int h, int new_wh)
	Calculates layout size recursively.
void	gp_widget_redraw (gp_widget *self)
	Requests widget repaint.
void	gp_widget_resize (gp_widget *self)
	Requests widget resize.
void	gp_widget_redraw_children (gp_widget *self)
	Redraw all child widgets.
void	gp_widget_render (gp_widget *self, const gp_widget_render_ctx *ctx, int new_wh)
	Resizes and redraws changed widgets.

Detailed Description

Widget internals.

You will not need to understand this part of the library unless you need to add a custom widget types.

Definition in file gp_widget_ops.h.

Enumeration Type Documentation

gp_widget_focus_flag

enum gp_widget_focus_flag

Flags to move focus around.

Enumerator
GP_FOCUS_OUT	Defocus any focused widget in the layout.
GP_FOCUS_IN	Focus first widget in the layout.
GP_FOCUS_LEFT	Moves focus left.
GP_FOCUS_RIGHT	Moves focus right.
GP_FOCUS_UP	Moves focus up.
GP_FOCUS_DOWN	Moves focus down.
GP_FOCUS_NEXT	Focus next widget.
GP_FOCUS_PREV	Focus previous widget.

Definition at line 27 of file gp_widget_ops.h.

gp_widget_render_flags

enum gp_widget_render_flags

Widget rendering flags.

Enumerator
GP_WIDGET_REDRAW	Widget needs to be repainted. Set by the widget to request a repaint next time the main loop returns to the library.
GP_WIDGET_COLOR_SCHEME	A color scheme has changed. Passed down from the widget render when color scheme changed and everything has to be repainted.
GP_WIDGET_RESIZE	Layout needs to be resized. TODO description.
GP_WIDGET_DISABLED	Widget is disabled. When a widget is disabled all it's children gets this flag passed down to their render functions.

Definition at line 54 of file gp_widget_ops.h.

Function Documentation

gp_widget_calc_size()

void gp_widget_calc_size	(	gp_widget *	layout,
		const gp_widget_render_ctx *	ctx,
		unsigned int	w,
		unsigned int	h,
		int	new_wh
	)

Calculates layout size recursively.

The size may end up larger than WxH if there is too much widgets or smaller than WxH if align is not set to fill.

Parameters

layout	Widget layout.
ctx	Render context, e.g. fonts, pixel type, padding size, etc.
w	Width we are trying to fit into
h	Height we are trying to fit into
new_wh	If set the layout size is recalculated, i.e. the layout size has changed.

gp_widget_ops_blit()

static void gp_widget_ops_blit ( const gp_widget_render_ctx *  ctx, gp_coord  x, gp_coord  y, gp_size  w, gp_size  h  )

inlinestatic

Marks an area to be blit on the screen from a buffer.

This function is called by widgets so that the render knows which parts of the screen has to be updated after the call to the render function.

Definition at line 324 of file gp_widget_ops.h.

References gp_bbox_empty(), gp_bbox_merge(), and gp_bbox_pack().

gp_widget_ops_event()

int gp_widget_ops_event	(	gp_widget *	self,
		const gp_widget_render_ctx *	ctx,
		gp_event *	ev
	)

Send an event to a widget.

Parameters

self	A widget to send the event to.
ctx	A render context.
ev	An input event.

Returns

Zero if event wasn't handled, non-zero otherwise.

gp_widget_ops_focus_widget()

int gp_widget_ops_focus_widget

(

gp_widget *

self

)

Moves focus to a particular widget.

Traverses the widget layout tree to the top and sets the focus accordingly.

Parameters

self	A widget to be focused.

Returns

Zero if focus couldn't be changed, non-zero otherwise.

gp_widget_ops_for_each_child()

void gp_widget_ops_for_each_child	(	gp_widget *	self,
		void(*)(gp_widget *child)	func
	)

Calls a callback on each child widget.

All non-leaf widgets must implement for_each_child() callback in its ops which is then called by this function.

This function is no-op for NULL self and non-leaf widgets.

Parameters

self	A widget.
func	A function callback

gp_widget_ops_render_focus()

int gp_widget_ops_render_focus	(	gp_widget *	self,
		int	focus_dir
	)

Moves focus, if possible, in the direction requested by the focus_dir.

Parameters

self	A widget layout.
focus_dir	Direction to move the focus to.

Returns

Zero if focus couldn't be moved, non-zero otherwise.

gp_widget_ops_render_focus_xy()

int gp_widget_ops_render_focus_xy	(	gp_widget *	self,
		const gp_widget_render_ctx *	ctx,
		unsigned int	x,
		unsigned int	y
	)

Tries to focus a widget on a given coordinates in a layout.

Parameters

self	A widget layout.
ctx	A render context.
x	X coordinate.
y	Y coordinate.

Returns

Zero if focus wasn't changed, non-zero otherwise.

gp_widget_redraw()

void gp_widget_redraw

(

gp_widget *

self

)

Requests widget repaint.

Marks widget to be repainted on next update.

Parameters

self

A widget.

gp_widget_redraw_children()

void gp_widget_redraw_children

(

gp_widget *

self

)

Redraw all child widgets.

Marks all children to be repainted on next update. This is used internally by container widgets when layout has changed, e.g. visible tab has changed.

Parameters

self	A container widget.

gp_widget_render()

void gp_widget_render	(	gp_widget *	self,
		const gp_widget_render_ctx *	ctx,
		int	new_wh
	)

Resizes and redraws changed widgets.

Parameters

self	A widget layout.
ctx	A rendering context.
new_wh	If set the layout size is recalculated, i.e. the layout size has changed.

gp_widget_resize()

void gp_widget_resize

(

gp_widget *

self

)

Requests widget resize.

Marks widget to be resized on next update. The resize is propagated in the layout to the top. E.g. if widget has to grow, the whole layout will.

Parameters

self

A widget.

gp_widget_should_redraw()

static int gp_widget_should_redraw ( gp_widget *  self, int  flags  )

inlinestatic

Returns true if widget should be repainted.

@self A widget. @flags Render flags passed down to the widget->render() function.

Returns

Non-zero if widget should be repainted.

Definition at line 345 of file gp_widget_ops.h.

References GP_WIDGET_REDRAW, and gp_widget::redraw.