Added extended selection capabilities to the API

backends/x/window.go

@@ -78,7 +78,7 @@ func (backend *Backend) NewWindow (
 func (window *Window) Adopt (child tomo.Element) {
 	if window.child != nil {
 		child.SetParentHooks (tomo.ParentHooks { })
-		if child.Selectable() { child.Handle(tomo.EventDeselect { }) }
+		if child.Selected() { child.Handle(tomo.EventDeselect { }) }
 	}
 	window.child = child
 	if child != nil {
@@ -87,12 +87,7 @@ func (window *Window) Adopt (child tomo.Element) {
 			MinimumSizeChange: window.childMinimumSizeChangeCallback,
 			SelectionRequest: window.childSelectionRequestCallback,
 		})
-		// TODO: it is possible for an element to start out as
-		// selectable, and then become unselectable. it should be
-		// standard behavior for containers (including windows) to, if
-		// no children are selected, select the first child on ctrl-tab
-		// press. we should therefore be able to ask any element if it
-		// is selected.
+		
 		if child.Selectable() { child.Handle(tomo.EventSelect { }) }
 		window.resizeChildToFit()
 	}

elements/basic/button.go

@@ -12,7 +12,6 @@ type Button struct {
 	
 	pressed  bool
 	enabled  bool
-	selected bool
 	onClick func ()
 
 	text   string
@@ -91,10 +90,10 @@ func (element *Button) Handle (event tomo.Event) {
 		}
 
 	case tomo.EventSelect:
-		element.selected = true
+		element.core.SetSelected(true)
 
 	case tomo.EventDeselect:
-		element.selected = false
+		element.core.SetSelected(false)
 	}
 	return
 }
@@ -103,16 +102,6 @@ func (element *Button) OnClick (callback func ()) {
 	element.onClick = callback
 }
 
-func (element *Button) AdvanceSelection (direction int) (ok bool) {
-	wasSelected := element.selected
-	element.selected = false
-	if element.core.HasImage() && wasSelected {
-		element.draw()
-		element.core.PushAll()
-	}
-	return
-}
-
 func (element *Button) Select () {
 	element.core.Select()
 }
@@ -150,7 +139,7 @@ func (element *Button) draw () {
 		theme.RaisedProfile (
 			element.pressed,
 			element.enabled,
-			element.selected),
+			element.Selected()),
 		bounds)
 		
 	innerBounds := bounds

elements/basic/container.go

@@ -13,6 +13,7 @@ type Container struct {
 	layout     tomo.Layout
 	children   []tomo.LayoutEntry
 	selectable bool
+	selected   bool
 
 	drags [10]tomo.Element
 }
@@ -183,6 +184,16 @@ func (element *Container) Handle (event tomo.Event) {
 				Y: mouseMoveEvent.Y - childPosition.Y,
 			})
 		}
+
+	case tomo.EventSelect:
+		if !element.Selectable() { break }
+		element.core.SetSelected(true)
+
+	case tomo.EventDeselect:
+		element.core.SetSelected(false)
+		// TODO: propogate deselect event to all children who report
+		// themselves as selected.
+		
 	}
 	return
 }
@@ -198,6 +209,7 @@ func (element *Container) updateSelectable () {
 		if entry.Selectable() { selectable = true }
 	}
 	element.core.SetSelectable(selectable)
+	if !selectable { element.selected = false }
 }
 
 func (element *Container) updateMinimumSize () {

elements/basic/label.go

@@ -84,10 +84,6 @@ func (element *Label) updateMinimumSize () {
 	}
 }
 
-func (element *Label) AdvanceSelection (direction int) (ok bool) {
-	return
-}
-
 func (element *Label) draw () {
 	bounds := element.core.Bounds()
 

elements/basic/test.go

@@ -3,6 +3,7 @@ package basic
 import "image"
 import "image/color"
 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"
 
@@ -33,9 +34,7 @@ func (element *Test) Handle (event tomo.Event) {
 			resizeEvent.Height)
 		artist.Rectangle (
 			element.core,
-			artist.NewUniform (color.RGBA {
-				R: 0x40, G: 0x80, B: 0x90, A: 0xFF,
-			}),
+			theme.AccentImage(),
 			artist.NewUniform(color.Black),
 			1, element.Bounds())
 		artist.Line (
@@ -46,7 +45,6 @@ func (element *Test) Handle (event tomo.Event) {
 			element.core, artist.NewUniform(color.White), 1,
 			image.Pt(1, resizeEvent.Height - 2),
 			image.Pt(resizeEvent.Width - 2, 1))
-		// println(resizeEvent.Width, resizeEvent.Height)
 	
 	case tomo.EventMouseDown:
 		element.drawing = true
@@ -78,7 +76,3 @@ func (element *Test) Handle (event tomo.Event) {
 	}
 	return
 }
-
-func (element *Test) AdvanceSelection (direction int) (ok bool) {
-	return
-}

elements/core/core.go

@@ -16,6 +16,7 @@ type Core struct {
 	}
 
 	selectable bool
+	selected   bool
 	hooks tomo.ParentHooks
 }
 
@@ -47,14 +48,22 @@ func (core Core) Bounds () (bounds image.Rectangle) {
 	return
 }
 
-func (core *Core) SetParentHooks (hooks tomo.ParentHooks) {
-	core.hooks = hooks
-}
-
 func (core Core) Selectable () (selectable bool) {
 	return core.selectable
 }
 
+func (core Core) Selected () (selected bool) {
+	return core.selected
+}
+
+func (core Core) AdvanceSelection (direction int) (ok bool) {
+	return
+}
+
+func (core *Core) SetParentHooks (hooks tomo.ParentHooks) {
+	core.hooks = hooks
+}
+
 func (core Core) MinimumSize () (width, height int) {
 	return core.metrics.minimumWidth, core.metrics.minimumHeight
 }
@@ -76,6 +85,18 @@ func (control CoreControl) Select () {
 	control.core.hooks.RunSelectionRequest()
 }
 
+func (control CoreControl) SetSelected (selected bool) {
+	if !control.core.selectable { return }
+	control.core.selected = selected
+}
+
+func (control CoreControl) SetSelectable (selectable bool) {
+	if control.core.selectable == selectable { return }
+	control.core.selectable = selectable
+	if !selectable { control.core.selected = false }
+	control.core.hooks.RunSelectabilityChange(selectable)
+}
+
 func (control CoreControl) PushRegion (bounds image.Rectangle) {
 	control.core.hooks.RunDraw(control.SubImage(bounds).(*image.RGBA))
 }
@@ -91,38 +112,31 @@ func (control *CoreControl) AllocateCanvas (width, height int) {
 	control.RGBA = core.canvas
 }
 
-func (control CoreControl) SetSelectable (selectable bool) {
-	changed := control.core.selectable != selectable
-	control.core.selectable = selectable
-	if changed {
-		control.core.hooks.RunSelectabilityChange(selectable)
-	}
-}
-
 func (control CoreControl) SetMinimumSize (width, height int) {
 	core := control.core
-	if width != core.metrics.minimumWidth ||
-		height != core.metrics.minimumHeight {
+	if width == core.metrics.minimumWidth &&
+		height == core.metrics.minimumHeight {
+		return
+	}
 
-		core.metrics.minimumWidth  = width
-		core.metrics.minimumHeight = height
-		core.hooks.RunMinimumSizeChange(width, height)
+	core.metrics.minimumWidth  = width
+	core.metrics.minimumHeight = height
+	core.hooks.RunMinimumSizeChange(width, height)
 
-		// if there is an image buffer, and the current size is less
-		// than this new minimum size, send core.parent a resize event.
-		if control.HasImage() {
-			bounds := control.Bounds()
-			imageWidth,
-			imageHeight,
-			constrained := control.ConstrainSize (
-				bounds.Dx(),
-				bounds.Dy())
-			if constrained {
-				core.parent.Handle (tomo.EventResize {
-					Width:  imageWidth,
-					Height: imageHeight,
-				})
-			}
+	// if there is an image buffer, and the current size is less
+	// than this new minimum size, send core.parent a resize event.
+	if control.HasImage() {
+		bounds := control.Bounds()
+		imageWidth,
+		imageHeight,
+		constrained := control.ConstrainSize (
+			bounds.Dx(),
+			bounds.Dy())
+		if constrained {
+			core.parent.Handle (tomo.EventResize {
+				Width:  imageWidth,
+				Height: imageHeight,
+			})
 		}
 	}
 }

theme/theme.go

@@ -12,7 +12,7 @@ import "git.tebibyte.media/sashakoshka/tomo/defaultfont"
 
 var foregroundImage  = artist.NewUniform(color.Gray16 { 0x0000})
 var disabledForegroundImage = artist.NewUniform(color.Gray16 { 0x5555})
-var accentImage      = artist.NewUniform(color.RGBA { 0x3E, 0x81, 0x69, 0xFF})
+var accentImage      = artist.NewUniform(color.RGBA { 0x40, 0x80, 0x90, 0xFF})
 var highlightImage   = artist.NewUniform(color.Gray16 { 0xEEEE })
 var shadowImage      = artist.NewUniform(color.Gray16 { 0x3333 })
 var weakShadeImage   = artist.NewUniform(color.Gray16 { 0x7777 })
@@ -24,7 +24,7 @@ var backgroundImage = artist.NewUniform(color.Gray16 { 0xAAAA})
 var backgroundProfile = artist.ShadingProfile {
 	Highlight:     highlightImage,
 	Shadow:        shadowImage,
-	Stroke:        artist.NewUniform(color.Gray16 { 0x0000 }),
+	Stroke:        strokeImage,
 	Fill:          backgroundImage,
 	StrokeWeight:  1,
 	ShadingWeight: 1,

tomo.go

@@ -90,7 +90,11 @@ type Element interface {
 
 	// Selectable returns whether this element can be selected. If this
 	// element contains other selectable elements, it must return true.
-	Selectable () (bool)
+	Selectable () (selectable bool)
+
+	// Selected returns wehther this element is currently selected. This
+	// will always return false if it is not selectable.
+	Selected () (selected bool)
 
 	// If this element contains other elements, and one is selected, this
 	// method will advance the selection in the specified direction. If no