From 56e11ae1de72970d87a819ecbdefdaffe53f5499 Mon Sep 17 00:00:00 2001 From: Sasha Koshka Date: Sat, 4 Mar 2023 01:05:37 -0500 Subject: [PATCH] Cleaned up the (ChildIterator -> Parent) interface --- elements/core/propagator.go | 74 +++++++++++++++++++------------------ 1 file changed, 39 insertions(+), 35 deletions(-) diff --git a/elements/core/propagator.go b/elements/core/propagator.go index 10b2566..d9b9081 100644 --- a/elements/core/propagator.go +++ b/elements/core/propagator.go @@ -6,11 +6,9 @@ import "git.tebibyte.media/sashakoshka/tomo/theme" import "git.tebibyte.media/sashakoshka/tomo/config" import "git.tebibyte.media/sashakoshka/tomo/elements" -// ChildIterator represents an object that can iterate over a list of children, -// calling a specified iterator function for each one. When keepGoing is false, -// the iterator stops the current loop and OverChildren returns. -type ChildIterator interface { - OverChildren (func (child elements.Element) (keepGoing bool)) +// Parent represents an object that can provide access to a list of child +// elements. +type Parent interface { Child (index int) elements.Element CountChildren () int } @@ -20,7 +18,7 @@ type ChildIterator interface { // all of the event handlers. It also implements standard behavior for focus // propagation and keyboard navigation. type Propagator struct { - iterator ChildIterator + parent Parent drags [10]elements.MouseTarget focused bool @@ -28,13 +26,13 @@ type Propagator struct { onFocusMotionRequest func (input.KeynavDirection) (granted bool) } -// NewPropagator creates a new event propagator that uses the specified iterator +// NewPropagator creates a new event propagator that uses the specified parent // to access a list of child elements that will have events propagated to them. -// If iterator is nil, the function will return nil. -func NewPropagator (iterator ChildIterator) (propagator *Propagator) { - if iterator == nil { return nil } +// If parent is nil, the function will return nil. +func NewPropagator (parent Parent) (propagator *Propagator) { + if parent == nil { return nil } propagator = &Propagator { - iterator: iterator, + parent: parent, } return } @@ -83,7 +81,7 @@ func (propagator *Propagator) HandleFocus (direction input.KeynavDirection) (acc // an element is currently focused, so we need to move the // focus in the specified direction firstFocusedChild := - propagator.iterator.Child(firstFocused). + propagator.parent.Child(firstFocused). (elements.Focusable) // before we move the focus, the currently focused child @@ -96,11 +94,11 @@ func (propagator *Propagator) HandleFocus (direction input.KeynavDirection) (acc // find the previous/next focusable element relative to the // currently focused element, if it exists. for index := firstFocused + int(direction); - index < propagator.iterator.CountChildren() && index >= 0; + index < propagator.parent.CountChildren() && index >= 0; index += int(direction) { child, focusable := - propagator.iterator.Child(index). + propagator.parent.Child(index). (elements.Focusable) if focusable && child.HandleFocus(direction) { // we have found one, so we now actually move @@ -222,7 +220,7 @@ func (propagator *Propagator) HandleMouseScroll (x, y int, deltaX, deltaY float6 // SetTheme sets the theme of all children to the specified theme. func (propagator *Propagator) SetTheme (theme theme.Theme) { - propagator.iterator.OverChildren (func (child elements.Element) bool { + propagator.forChildren (func (child elements.Element) bool { typedChild, themeable := child.(elements.Themeable) if themeable { typedChild.SetTheme(theme) @@ -233,7 +231,7 @@ func (propagator *Propagator) SetTheme (theme theme.Theme) { // SetConfig sets the theme of all children to the specified config. func (propagator *Propagator) SetConfig (config config.Config) { - propagator.iterator.OverChildren (func (child elements.Element) bool { + propagator.forChildren (func (child elements.Element) bool { typedChild, configurable := child.(elements.Configurable) if configurable { typedChild.SetConfig(config) @@ -265,32 +263,38 @@ func (propagator *Propagator) focusLastFocusableElement ( ) ( ok bool, ) { - focusables := []elements.Focusable { } - propagator.forFocusable (func (child elements.Focusable) bool { - focusables = append(focusables, child) - return true - }) - - for index := len(focusables) - 1; index >= 0; index -- { - child, focusable := focusables[index].(elements.Focusable) - if focusable && child.HandleFocus(direction) { + propagator.forChildrenReverse (func (child elements.Element) bool { + typedChild, focusable := child.(elements.Focusable) + if focusable && typedChild.HandleFocus(direction) { propagator.focused = true ok = true - break + return false } - } + return true + }) return } - // ----------- Iterator utilities ----------- // -// TODO: remove ChildIterator.OverChildren, reimplement that here, rework these -// methods based on that, add a reverse iteration method, and then rework -// focusLastFocusableElement based on that. +func (propagator *Propagator) forChildren (callback func (child elements.Element) bool) { + for index := 0; index < propagator.parent.CountChildren(); index ++ { + child := propagator.parent.Child(index) + if child == nil { continue } + if callback(child) { break } + } +} + +func (propagator *Propagator) forChildrenReverse (callback func (child elements.Element) bool) { + for index := propagator.parent.CountChildren() - 1; index > 0; index -- { + child := propagator.parent.Child(index) + if child == nil { continue } + if callback(child) { break } + } +} func (propagator *Propagator) childAt (position image.Point) (child elements.Element) { - propagator.iterator.OverChildren (func (current elements.Element) bool { + propagator.forChildren (func (current elements.Element) bool { if position.In(current.Bounds()) { child = current } @@ -300,7 +304,7 @@ func (propagator *Propagator) childAt (position image.Point) (child elements.Ele } func (propagator *Propagator) forFocused (callback func (child elements.Focusable) bool) { - propagator.iterator.OverChildren (func (child elements.Element) bool { + propagator.forChildren (func (child elements.Element) bool { typedChild, focusable := child.(elements.Focusable) if focusable && typedChild.Focused() { if !callback(typedChild) { return false } @@ -310,7 +314,7 @@ func (propagator *Propagator) forFocused (callback func (child elements.Focusabl } func (propagator *Propagator) forFocusable (callback func (child elements.Focusable) bool) { - propagator.iterator.OverChildren (func (child elements.Element) bool { + propagator.forChildren (func (child elements.Element) bool { typedChild, focusable := child.(elements.Focusable) if focusable { if !callback(typedChild) { return false } @@ -320,7 +324,7 @@ func (propagator *Propagator) forFocusable (callback func (child elements.Focusa } func (propagator *Propagator) forFlexible (callback func (child elements.Flexible) bool) { - propagator.iterator.OverChildren (func (child elements.Element) bool { + propagator.forChildren (func (child elements.Element) bool { typedChild, flexible := child.(elements.Flexible) if flexible { if !callback(typedChild) { return false }