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()) }