driver

Documentation

Index

• func AbsolutePositionForObject(object fyne.CanvasObject, trees []fyne.CanvasObject) fyne.Position
• func FindObjectAtPositionMatching(mouse fyne.Position, matches func(object fyne.CanvasObject) bool, ...) (fyne.CanvasObject, fyne.Position, int)
• func WalkCompleteObjectTree(obj fyne.CanvasObject, ...) bool
• func WalkVisibleObjectTree(obj fyne.CanvasObject, ...) bool
• type WithContext

Functions

func AbsolutePositionForObject

func AbsolutePositionForObject(object fyne.CanvasObject, trees []fyne.CanvasObject) fyne.Position

AbsolutePositionForObject returns the absolute position of an object in a set of object trees. If the object is not part of any of the trees, the position (0,0) is returned.

func FindObjectAtPositionMatching

func FindObjectAtPositionMatching(mouse fyne.Position, matches func(object fyne.CanvasObject) bool, overlay fyne.CanvasObject, roots ...fyne.CanvasObject) (fyne.CanvasObject, fyne.Position, int)

FindObjectAtPositionMatching is used to find an object in a canvas at the specified position. The matches function determines of the type of object that is found at this position is of a suitable type. The various canvas roots and overlays that can be searched are also passed in.

func WalkCompleteObjectTree

func WalkCompleteObjectTree(
	obj fyne.CanvasObject,
	beforeChildren func(fyne.CanvasObject, fyne.Position, fyne.Position, fyne.Size) bool,
	afterChildren func(fyne.CanvasObject, fyne.CanvasObject),
) bool

WalkCompleteObjectTree will walk an object tree for all objects (ignoring visible state) executing the passed functions following the following rules: - beforeChildren is called for the start obj before traversing its children - the obj's children are traversed by calling walkObjects on each of the items - afterChildren is called for the obj after traversing the obj's children The walk can be aborted by returning true in one of the functions:

• if beforeChildren returns true, further traversing is stopped immediately, the after function will not be called for the obj where the walk stopped, however, it will be called for all its parents

func WalkVisibleObjectTree

func WalkVisibleObjectTree(
	obj fyne.CanvasObject,
	beforeChildren func(fyne.CanvasObject, fyne.Position, fyne.Position, fyne.Size) bool,
	afterChildren func(fyne.CanvasObject, fyne.CanvasObject),
) bool

WalkVisibleObjectTree will walk an object tree for all visible objects executing the passed functions following the following rules: - beforeChildren is called for the start obj before traversing its children - the obj's children are traversed by calling walkObjects on each of the visible items - afterChildren is called for the obj after traversing the obj's children The walk can be aborted by returning true in one of the functions:

• if beforeChildren returns true, further traversing is stopped immediately, the after function will not be called for the obj where the walk stopped, however, it will be called for all its parents

Types

type WithContext

type WithContext interface {
	RunWithContext(f func())
	RescaleContext()
	Context() interface{}
}

WithContext allows drivers to execute within another context. Mostly this helps GLFW code execute within the painter's GL context.