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tomo-old/elements/basic/container.go
2023-01-31 18:04:12 -05:00

476 lines
13 KiB
Go

package basic
import "image"
import "git.tebibyte.media/sashakoshka/tomo"
import "git.tebibyte.media/sashakoshka/tomo/theme"
import "git.tebibyte.media/sashakoshka/tomo/artist"
import "git.tebibyte.media/sashakoshka/tomo/elements/core"
var containerCase = theme.C("basic", "container")
// Container is an element capable of containg other elements, and arranging
// them in a layout.
type Container struct {
*core.Core
core core.CoreControl
layout tomo.Layout
children []tomo.LayoutEntry
drags [10]tomo.MouseTarget
warping bool
focused bool
focusable bool
flexible bool
onFocusRequest func () (granted bool)
onFocusMotionRequest func (tomo.KeynavDirection) (granted bool)
onFlexibleHeightChange func ()
}
// NewContainer creates a new container.
func NewContainer (layout tomo.Layout) (element *Container) {
element = &Container { }
element.Core, element.core = core.NewCore(element.redoAll)
element.SetLayout(layout)
return
}
// SetLayout sets the layout of this container.
func (element *Container) SetLayout (layout tomo.Layout) {
element.layout = layout
if element.core.HasImage() {
element.redoAll()
element.core.DamageAll()
}
}
// Adopt adds a new child element to the container. If expand is set to true,
// the element will expand (instead of contract to its minimum size), in
// whatever way is defined by the current layout.
func (element *Container) Adopt (child tomo.Element, expand bool) {
// set event handlers
child.OnDamage (func (region tomo.Canvas) {
element.core.DamageRegion(region.Bounds())
})
child.OnMinimumSizeChange(element.updateMinimumSize)
if child0, ok := child.(tomo.Flexible); ok {
child0.OnFlexibleHeightChange(element.updateMinimumSize)
}
if child0, ok := child.(tomo.Focusable); ok {
child0.OnFocusRequest (func () (granted bool) {
return element.childFocusRequestCallback(child0)
})
child0.OnFocusMotionRequest (
func (direction tomo.KeynavDirection) (granted bool) {
if element.onFocusMotionRequest == nil { return }
return element.onFocusMotionRequest(direction)
})
}
// add child
element.children = append (element.children, tomo.LayoutEntry {
Element: child,
Expand: expand,
})
// refresh stale data
element.updateMinimumSize()
element.reflectChildProperties()
if element.core.HasImage() && !element.warping {
element.redoAll()
element.core.DamageAll()
}
}
// Warp runs the specified callback, deferring all layout and rendering updates
// until the callback has finished executing. This allows for aplications to
// perform batch gui updates without flickering and stuff.
func (element *Container) Warp (callback func ()) {
if element.warping {
callback()
return
}
element.warping = true
callback()
element.warping = false
// TODO: create some sort of task list so we don't do a full recalculate
// and redraw every time, because although that is the most likely use
// case, it is not the only one.
if element.core.HasImage() {
element.redoAll()
element.core.DamageAll()
}
}
// Disown removes the given child from the container if it is contained within
// it.
func (element *Container) Disown (child tomo.Element) {
for index, entry := range element.children {
if entry.Element == child {
element.clearChildEventHandlers(entry.Element)
element.children = append (
element.children[:index],
element.children[index + 1:]...)
break
}
}
element.updateMinimumSize()
element.reflectChildProperties()
if element.core.HasImage() && !element.warping {
element.redoAll()
element.core.DamageAll()
}
}
func (element *Container) clearChildEventHandlers (child tomo.Element) {
child.DrawTo(nil)
child.OnDamage(nil)
child.OnMinimumSizeChange(nil)
if child0, ok := child.(tomo.Focusable); ok {
child0.OnFocusRequest(nil)
child0.OnFocusMotionRequest(nil)
if child0.Focused() {
child0.HandleUnfocus()
}
}
if child0, ok := child.(tomo.Flexible); ok {
child0.OnFlexibleHeightChange(nil)
}
}
// DisownAll removes all child elements from the container at once.
func (element *Container) DisownAll () {
element.children = nil
element.updateMinimumSize()
element.reflectChildProperties()
if element.core.HasImage() && !element.warping {
element.redoAll()
element.core.DamageAll()
}
}
// Children returns a slice containing this element's children.
func (element *Container) Children () (children []tomo.Element) {
children = make([]tomo.Element, len(element.children))
for index, entry := range element.children {
children[index] = entry.Element
}
return
}
// CountChildren returns the amount of children contained within this element.
func (element *Container) CountChildren () (count int) {
return len(element.children)
}
// Child returns the child at the specified index. If the index is out of
// bounds, this method will return nil.
func (element *Container) Child (index int) (child tomo.Element) {
if index < 0 || index > len(element.children) { return }
return element.children[index].Element
}
// ChildAt returns the child that contains the specified x and y coordinates. If
// there are no children at the coordinates, this method will return nil.
func (element *Container) ChildAt (point image.Point) (child tomo.Element) {
for _, entry := range element.children {
if point.In(entry.Bounds) {
child = entry.Element
}
}
return
}
func (element *Container) childPosition (child tomo.Element) (position image.Point) {
for _, entry := range element.children {
if entry.Element == child {
position = entry.Bounds.Min
break
}
}
return
}
func (element *Container) redoAll () {
// do a layout
element.recalculate()
// draw a background
bounds := element.Bounds()
pattern, _ := theme.BackgroundPattern (theme.PatternState {
Case: containerCase,
})
artist.FillRectangle(element, pattern, bounds)
// cut our canvas up and give peices to child elements
for _, entry := range element.children {
entry.DrawTo(tomo.Cut(element, entry.Bounds))
}
}
func (element *Container) HandleMouseDown (x, y int, button tomo.Button) {
child, handlesMouse := element.ChildAt(image.Pt(x, y)).(tomo.MouseTarget)
if !handlesMouse { return }
element.drags[button] = child
child.HandleMouseDown(x, y, button)
}
func (element *Container) HandleMouseUp (x, y int, button tomo.Button) {
child := element.drags[button]
if child == nil { return }
element.drags[button] = nil
child.HandleMouseUp(x, y, button)
}
func (element *Container) HandleMouseMove (x, y int) {
for _, child := range element.drags {
if child == nil { continue }
child.HandleMouseMove(x, y)
}
}
func (element *Container) HandleMouseScroll (x, y int, deltaX, deltaY float64) {
child, handlesMouse := element.ChildAt(image.Pt(x, y)).(tomo.MouseTarget)
if !handlesMouse { return }
child.HandleMouseScroll(x, y, deltaX, deltaY)
}
func (element *Container) HandleKeyDown (key tomo.Key, modifiers tomo.Modifiers) {
element.forFocused (func (child tomo.Focusable) bool {
child0, handlesKeyboard := child.(tomo.KeyboardTarget)
if handlesKeyboard {
child0.HandleKeyDown(key, modifiers)
}
return true
})
}
func (element *Container) HandleKeyUp (key tomo.Key, modifiers tomo.Modifiers) {
element.forFocused (func (child tomo.Focusable) bool {
child0, handlesKeyboard := child.(tomo.KeyboardTarget)
if handlesKeyboard {
child0.HandleKeyUp(key, modifiers)
}
return true
})
}
func (element *Container) FlexibleHeightFor (width int) (height int) {
return element.layout.FlexibleHeightFor(element.children, width)
}
func (element *Container) OnFlexibleHeightChange (callback func ()) {
element.onFlexibleHeightChange = callback
}
func (element *Container) Focused () (focused bool) {
return element.focused
}
func (element *Container) Focus () {
if element.onFocusRequest != nil {
element.onFocusRequest()
}
}
func (element *Container) HandleFocus (direction tomo.KeynavDirection) (ok bool) {
if !element.focusable { return false }
direction = direction.Canon()
firstFocused := element.firstFocused()
if firstFocused < 0 {
// no element is currently focused, so we need to focus either
// the first or last focusable element depending on the
// direction.
switch direction {
case tomo.KeynavDirectionNeutral, tomo.KeynavDirectionForward:
// if we recieve a neutral or forward direction, focus
// the first focusable element.
return element.focusFirstFocusableElement(direction)
case tomo.KeynavDirectionBackward:
// if we recieve a backward direction, focus the last
// focusable element.
return element.focusLastFocusableElement(direction)
}
} else {
// an element is currently focused, so we need to move the
// focus in the specified direction
firstFocusedChild :=
element.children[firstFocused].Element.(tomo.Focusable)
// before we move the focus, the currently focused child
// may also be able to move its focus. if the child is able
// to do that, we will let it and not move ours.
if firstFocusedChild.HandleFocus(direction) {
return true
}
// find the previous/next focusable element relative to the
// currently focused element, if it exists.
for index := firstFocused + int(direction);
index < len(element.children) && index >= 0;
index += int(direction) {
child, focusable :=
element.children[index].
Element.(tomo.Focusable)
if focusable && child.HandleFocus(direction) {
// we have found one, so we now actually move
// the focus.
firstFocusedChild.HandleUnfocus()
element.focused = true
return true
}
}
}
return false
}
func (element *Container) focusFirstFocusableElement (
direction tomo.KeynavDirection,
) (
ok bool,
) {
element.forFocusable (func (child tomo.Focusable) bool {
if child.HandleFocus(direction) {
element.focused = true
ok = true
return false
}
return true
})
return
}
func (element *Container) focusLastFocusableElement (
direction tomo.KeynavDirection,
) (
ok bool,
) {
element.forFocusableBackward (func (child tomo.Focusable) bool {
if child.HandleFocus(direction) {
element.focused = true
ok = true
return false
}
return true
})
return
}
func (element *Container) HandleUnfocus () {
element.focused = false
element.forFocused (func (child tomo.Focusable) bool {
child.HandleUnfocus()
return true
})
}
func (element *Container) OnFocusRequest (callback func () (granted bool)) {
element.onFocusRequest = callback
}
func (element *Container) OnFocusMotionRequest (
callback func (direction tomo.KeynavDirection) (granted bool),
) {
element.onFocusMotionRequest = callback
}
func (element *Container) forFocused (callback func (child tomo.Focusable) bool) {
for _, entry := range element.children {
child, focusable := entry.Element.(tomo.Focusable)
if focusable && child.Focused() {
if !callback(child) { break }
}
}
}
func (element *Container) forFocusable (callback func (child tomo.Focusable) bool) {
for _, entry := range element.children {
child, focusable := entry.Element.(tomo.Focusable)
if focusable {
if !callback(child) { break }
}
}
}
func (element *Container) forFlexible (callback func (child tomo.Flexible) bool) {
for _, entry := range element.children {
child, flexible := entry.Element.(tomo.Flexible)
if flexible {
if !callback(child) { break }
}
}
}
func (element *Container) forFocusableBackward (callback func (child tomo.Focusable) bool) {
for index := len(element.children) - 1; index >= 0; index -- {
child, focusable := element.children[index].Element.(tomo.Focusable)
if focusable {
if !callback(child) { break }
}
}
}
func (element *Container) firstFocused () (index int) {
for currentIndex, entry := range element.children {
child, focusable := entry.Element.(tomo.Focusable)
if focusable && child.Focused() {
return currentIndex
}
}
return -1
}
func (element *Container) reflectChildProperties () {
element.focusable = false
element.forFocusable (func (tomo.Focusable) bool {
element.focusable = true
return false
})
element.flexible = false
element.forFlexible (func (tomo.Flexible) bool {
element.flexible = true
return false
})
if !element.focusable {
element.focused = false
}
}
func (element *Container) childFocusRequestCallback (
child tomo.Focusable,
) (
granted bool,
) {
if element.onFocusRequest != nil && element.onFocusRequest() {
element.forFocused (func (child tomo.Focusable) bool {
child.HandleUnfocus()
return true
})
child.HandleFocus(tomo.KeynavDirectionNeutral)
return true
} else {
return false
}
}
func (element *Container) updateMinimumSize () {
width, height := element.layout.MinimumSize(element.children)
if element.flexible {
height = element.layout.FlexibleHeightFor(element.children, width)
}
element.core.SetMinimumSize(width, height)
}
func (element *Container) recalculate () {
element.layout.Arrange(element.children, element.Bounds())
}