artist/text.go

@@ -17,6 +17,7 @@ type wordLayout struct {
 	position    image.Point
 	width       int
 	spaceAfter  int
+	breaksAfter int
 	text        []characterLayout
 }
 
@@ -167,13 +168,16 @@ func (drawer *TextDrawer) LineHeight () (height fixed.Int26_6) {
 func (drawer *TextDrawer) ReccomendedHeightFor (width int) (height int) {
 	if !drawer.layoutClean { drawer.recalculate() }
 	metrics := drawer.face.Metrics()
-	dot := fixed.Point26_6 { 0, 0 }
+	dot := fixed.Point26_6 { 0, metrics.Height }
 	for _, word := range drawer.layout {
-		dot.X += fixed.Int26_6((word.width + word.spaceAfter) << 6)
-		
-		if word.width + word.position.X > width && word.position.X > 0 {
+		if word.width + dot.X.Round() > width {
 			dot.Y += metrics.Height
-			dot.X = fixed.Int26_6(word.width << 6)
+			dot.X = 0
+		}
+		dot.X += fixed.I(word.width + word.spaceAfter)
+		if word.breaksAfter > 0 {
+			dot.Y += fixed.I(word.breaksAfter).Mul(metrics.Height)
+			dot.X = 0
 		}
 	}
 
@@ -246,6 +250,7 @@ func (drawer *TextDrawer) recalculate () {
 			if character == '\n' {
 				dot.Y += metrics.Height
 				dot.X = 0
+				word.breaksAfter ++
 				previousCharacter = character
 				index ++
 			} else {
@@ -290,7 +295,6 @@ func (drawer *TextDrawer) recalculate () {
 
 	if drawer.wrap {
 		drawer.layoutBounds.Max.X = drawer.width
-		println("aaa")
 	} else {
 		drawer.layoutBounds.Max.X = horizontalExtent
 	}

backends/x/window.go

@@ -89,6 +89,7 @@ func (window *Window) Adopt (child tomo.Element) {
 		child.SetParentHooks (tomo.ParentHooks {
 			Draw: window.childDrawCallback,
 			MinimumSizeChange: window.childMinimumSizeChangeCallback,
+			FlexibleHeightChange: window.resizeChildToFit,
 			SelectionRequest: window.childSelectionRequestCallback,
 		})
 		
@@ -202,11 +203,27 @@ func (window *Window) redrawChildEntirely () {
 
 func (window *Window) resizeChildToFit () {
 	window.skipChildDrawCallback = true
-	if child, ok := window.child.(tomo.Expanding); ok {
+	if child, ok := window.child.(tomo.Flexible); ok {
 		minimumHeight := child.MinimumHeightFor(window.metrics.width)
-		_, minimumWidth := child.MinimumSize()
-		window.childMinimumSizeChangeCallback (
-			minimumWidth, minimumHeight)
+		minimumWidth, _ := child.MinimumSize()
+		
+		icccm.WmNormalHintsSet (
+			window.backend.connection,
+			window.xWindow.Id,
+			&icccm.NormalHints {
+				Flags:     icccm.SizeHintPMinSize,
+				MinWidth:  uint(minimumWidth),
+				MinHeight: uint(minimumHeight),
+			})
+				
+		if window.metrics.height >= minimumHeight &&
+			window.metrics.width >= minimumWidth {
+
+			window.child.Resize (
+				window.metrics.width,
+				window.metrics.height)
+				window.redrawChildEntirely()
+		}
 	} else {
 		window.child.Resize (
 			window.metrics.width,
@@ -261,6 +278,20 @@ func (window *Window) childSelectionRequestCallback () (granted bool) {
 	return true
 }
 
+func (window *Window) childSelectionMotionRequestCallback (
+	direction tomo.SelectionDirection,
+) (
+	granted bool,
+) {
+	if child, ok := window.child.(tomo.Selectable); ok {
+		if !child.HandleSelection(direction) {
+			child.HandleDeselection()
+		}
+		return true
+	}
+	return true
+}
+
 func (window *Window) pushRegion (region image.Rectangle) {
 	if window.xCanvas == nil { panic("whoopsie!!!!!!!!!!!!!!") }
 	image, ok := window.xCanvas.SubImage(region).(*xgraphics.Image)

element.go

@@ -3,7 +3,8 @@ package tomo
 // ParentHooks is a struct that contains callbacks that let child elements send
 // information to their parent element without the child element knowing
 // anything about the parent element or containing any reference to it. When a
-// parent element adopts a child element, it must set these callbacks.
+// parent element adopts a child element, it must set these callbacks. They are
+// allowed to be nil.
 type ParentHooks struct {
 	// Draw is called when a part of the child element's surface is updated.
 	// The updated region will be passed to the callback as a sub-image.
@@ -15,11 +16,19 @@ type ParentHooks struct {
 	// event.
 	MinimumSizeChange func (width, height int)
 
+	// FlexibleHeightChange is called when the parameters affecting the
+	// element's expanding height have changed.
+	FlexibleHeightChange func ()
+	
 	// SelectionRequest is called when the child element element wants
 	// itself to be selected. If the parent element chooses to grant the
 	// request, it must send the child element a selection event and return
 	// true.
 	SelectionRequest func () (granted bool)
+
+	// SelectionMotionRequest is called when the child element wants the
+	// parent element to select the previous/next element in relation to it.
+	SelectionMotionRequest func (direction SelectionDirection) (granted bool)
 }
 
 // RunDraw runs the Draw hook if it is not nil. If it is nil, it does nothing.
@@ -37,6 +46,14 @@ func (hooks ParentHooks) RunMinimumSizeChange (width, height int) {
 	}
 }
 
+// RunFlexibleHeightChange runs the ExpandingHeightChange hook if it is not
+// nil. If it is nil, it does nothing.
+func (hooks ParentHooks) RunFlexibleHeightChange () {
+	if hooks.FlexibleHeightChange != nil {
+		hooks.FlexibleHeightChange()
+	}
+}
+
 // RunSelectionRequest runs the SelectionRequest hook if it is not nil. If it is
 // nil, it does nothing.
 func (hooks ParentHooks) RunSelectionRequest () (granted bool) {
@@ -46,6 +63,19 @@ func (hooks ParentHooks) RunSelectionRequest () (granted bool) {
 	return
 }
 
+// RunSelectionMotionRequest runs the SelectionMotionRequest hook if it is not
+// nil. If it is nil, it does nothing.
+func (hooks ParentHooks) RunSelectionMotionRequest (
+	direction SelectionDirection,
+) (
+	granted bool,
+) {
+	if hooks.SelectionMotionRequest != nil {
+		granted = hooks.SelectionMotionRequest(direction)
+	}
+	return
+}
+
 // Element represents a basic on-screen object.
 type Element interface {
 	// Element must implement the Canvas interface. Elements should start
@@ -153,9 +183,9 @@ type MouseTarget interface {
 	HandleScroll (x, y int, deltaX, deltaY float64)
 }
 
-// Expanding represents an element who's preferred minimum height can change in
+// Flexible represents an element who's preferred minimum height can change in
 // response to its width.
-type Expanding interface {
+type Flexible interface {
 	Element
 
 	// HeightForWidth returns what the element's minimum height would be if
@@ -170,6 +200,6 @@ type Expanding interface {
 	// minimum size that the element may be resized to.
 	//
 	// It is important to note that if a parent container checks for
-	// expanding chilren, it itself will likely need to be expanding.
+	// flexible chilren, it itself will likely need to be flexible.
 	MinimumHeightFor (width int) (height int)
 }

elements/basic/button.go

@@ -103,6 +103,7 @@ func (element *Button) HandleSelection (
 ) (
 	accepted bool,
 ) {
+	direction = direction.Canon()
 	if !element.enabled { return false }
 	if element.selected && direction != tomo.SelectionDirectionNeutral {
 		return false

elements/basic/container.go

@@ -18,6 +18,7 @@ type Container struct {
 	warping    bool
 	selected   bool
 	selectable bool
+	flexible   bool
 }
 
 // NewContainer creates a new container.
@@ -43,16 +44,24 @@ func (element *Container) SetLayout (layout tomo.Layout) {
 // whatever way is defined by the current layout.
 func (element *Container) Adopt (child tomo.Element, expand bool) {
 	child.SetParentHooks (tomo.ParentHooks {
+		Draw: func (region tomo.Canvas) {
+			element.drawChildRegion(child, region)
+		},
 		MinimumSizeChange: func (int, int) {
 			element.updateMinimumSize()
 		},
+		FlexibleHeightChange: element.updateMinimumSize,
 		SelectionRequest: func () (granted bool) {
 			child, selectable := child.(tomo.Selectable)
 			if !selectable { return }
 			return element.childSelectionRequestCallback(child)
 		},
-		Draw: func (region tomo.Canvas) {
-			element.drawChildRegion(child, region)
+		SelectionMotionRequest: func (
+			direction tomo.SelectionDirection,
+		) (
+			granted bool,
+		) {
+			return element.core.RequestSelectionMotion(direction)
 		},
 	})
 	element.children = append (element.children, tomo.LayoutEntry {
@@ -61,7 +70,7 @@ func (element *Container) Adopt (child tomo.Element, expand bool) {
 	})
 
 	element.updateMinimumSize()
-	element.updateSelectable()
+	element.reflectChildProperties()
 	if element.core.HasImage() && !element.warping {
 		element.recalculate()
 		element.draw()
@@ -106,7 +115,7 @@ func (element *Container) Disown (child tomo.Element) {
 	}
 
 	element.updateMinimumSize()
-	element.updateSelectable()
+	element.reflectChildProperties()
 	if element.core.HasImage() && !element.warping {
 		element.recalculate()
 		element.draw()
@@ -119,7 +128,7 @@ func (element *Container) DisownAll () {
 	element.children = nil
 
 	element.updateMinimumSize()
-	element.updateSelectable()
+	element.reflectChildProperties()
 	if element.core.HasImage() && !element.warping {
 		element.recalculate()
 		element.draw()
@@ -176,8 +185,6 @@ func (element *Container) Resize (width, height int) {
 	element.draw()
 }
 
-// TODO: implement KeyboardTarget
-
 func (element *Container) HandleMouseDown (x, y int, button tomo.Button) {
 	child, handlesMouse := element.ChildAt(image.Pt(x, y)).(tomo.MouseTarget)
 	if !handlesMouse { return }
@@ -223,7 +230,7 @@ func (element *Container) HandleKeyDown (
 	})
 }
 
-func (element *Container) HandleKeyUp(key tomo.Key, modifiers tomo.Modifiers) {
+func (element *Container) HandleKeyUp (key tomo.Key, modifiers tomo.Modifiers) {
 	element.forSelected (func (child tomo.Selectable) bool {
 		child0, handlesKeyboard := child.(tomo.KeyboardTarget)
 		if handlesKeyboard {
@@ -293,6 +300,10 @@ func (element *Container) HandleSelection (direction tomo.SelectionDirection) (o
 	return false
 }
 
+func (element *Container) MinimumHeightFor (width int) (height int) {
+	return element.layout.MinimumHeightFor(element.children, width)
+}
+
 func (element *Container) HandleDeselection () {
 	element.selected = false
 	element.forSelected (func (child tomo.Selectable) bool {
@@ -319,6 +330,15 @@ func (element *Container) forSelectable (callback func (child tomo.Selectable) b
 	}
 }
 
+func (element *Container) forFlexible (callback func (child tomo.Flexible) bool) {
+	for _, entry := range element.children {
+		child, selectable := entry.Element.(tomo.Flexible)
+		if selectable {
+			if !callback(child) { break }
+		}
+	}
+}
+
 func (element *Container) forSelectableBackward (callback func (child tomo.Selectable) bool) {
 	for index := len(element.children) - 1; index >= 0; index -- {
 		child, selectable := element.children[index].Element.(tomo.Selectable)
@@ -338,12 +358,17 @@ func (element *Container) firstSelected () (index int) {
 	return -1
 }
 
-func (element *Container) updateSelectable () {
+func (element *Container) reflectChildProperties () {
 	element.selectable = false
 	element.forSelectable (func (tomo.Selectable) bool {
 		element.selectable = true
 		return false
 	})
+	element.flexible = false
+	element.forFlexible (func (tomo.Flexible) bool {
+		element.flexible = true
+		return false
+	})
 	if !element.selectable {
 		element.selected = false
 	}
@@ -367,8 +392,11 @@ func (element *Container) childSelectionRequestCallback (
 }
 
 func (element *Container) updateMinimumSize () {
-	element.core.SetMinimumSize (
-		element.layout.MinimumSize(element.children, 1e9))
+	width, height := element.layout.MinimumSize(element.children)
+	if element.flexible {
+		height = element.layout.MinimumHeightFor(element.children, width)
+	}
+	element.core.SetMinimumSize(width, height)
 }
 
 func (element *Container) recalculate () {

elements/basic/label.go

@@ -27,6 +27,7 @@ func NewLabel (text string, wrap bool) (element *Label) {
 	return
 }
 
+// Resize resizes the label and re-wraps the text if wrapping is enabled.
 func (element *Label) Resize (width, height int) {
 	element.core.AllocateCanvas(width, height)
 	if element.wrap {
@@ -37,6 +38,17 @@ func (element *Label) Resize (width, height int) {
 	return
 }
 
+// MinimumHeightFor returns the reccomended height for this element based on the
+// given width in order to allow the text to wrap properly.
+func (element *Label) MinimumHeightFor (width int) (height int) {
+	if element.wrap {
+		return element.drawer.ReccomendedHeightFor(width)
+	} else {
+		_, height = element.MinimumSize()
+		return
+	}
+}
+
 // SetText sets the label's text.
 func (element *Label) SetText (text string) {
 	if element.text == text { return }
@@ -76,6 +88,7 @@ func (element *Label) updateMinimumSize () {
 		if em < 1 { em = theme.Padding() }
 		element.core.SetMinimumSize (
 			em, element.drawer.LineHeight().Round())
+		element.core.NotifyFlexibleHeightChange()
 	} else {
 		bounds := element.drawer.LayoutBounds()
 		element.core.SetMinimumSize(bounds.Dx(), bounds.Dy())

elements/core/core.go

@@ -80,6 +80,18 @@ func (control CoreControl) RequestSelection () (granted bool) {
 	return control.core.hooks.RunSelectionRequest()
 }
 
+// RequestSelectionMotion requests that the element's parent deselect this
+// element and select the one to the left or right of it, depending on the
+// direction. If the requests was granted, it returns true. If it was denied, it
+// returns false.
+func (control CoreControl) RequestSelectionMotion (
+	direction tomo.SelectionDirection,
+) (
+	granted bool,
+) {
+	return control.core.hooks.RunSelectionMotionRequest(direction)
+}
+
 // HasImage returns true if the core has an allocated image buffer, and false if
 // it doesn't.
 func (control CoreControl) HasImage () (has bool) {
@@ -101,7 +113,6 @@ func (control CoreControl) PushAll () {
 // AllocateCanvas resizes the canvas, constraining the width and height so that
 // they are not less than the specified minimum width and height.
 func (control *CoreControl) AllocateCanvas (width, height int) {
-	width, height, _ = control.ConstrainSize(width, height)
 	control.core.canvas = tomo.NewBasicCanvas(width, height)
 	control.BasicCanvas = control.core.canvas
 }
@@ -132,6 +143,12 @@ func (control CoreControl) SetMinimumSize (width, height int) {
 	}
 }
 
+// NotifyFlexibleHeightChange notifies the parent element that this element's
+// flexible height has changed.
+func (control CoreControl) NotifyFlexibleHeightChange () {
+	control.core.hooks.RunFlexibleHeightChange()
+}
+
 // ConstrainSize contstrains the specified width and height to the minimum width
 // and height, and returns wether or not anything ended up being constrained.
 func (control CoreControl) ConstrainSize (

examples/flow/main.go

@@ -21,7 +21,7 @@ func run () {
 	world.Stages = map [string] func () {
 		"start": func () {
 			label := basic.NewLabel (
-				"you are standing next to a river.", false)
+				"you are standing next to a river.", true)
 			
 			button0 := basic.NewButton("go in the river")
 			button0.OnClick(world.SwitchFunc("wet"))
@@ -41,7 +41,7 @@ func run () {
 		"wet": func () {
 			label := basic.NewLabel (
 				"you get completely soaked.\n" +
-				"you die of hypothermia.", false)
+				"you die of hypothermia.", true)
 			
 			button0 := basic.NewButton("try again")
 			button0.OnClick(world.SwitchFunc("start"))
@@ -58,7 +58,7 @@ func run () {
 		"house": func () {
 			label := basic.NewLabel (
 				"you are standing in front of a delapidated " +
-				"house.", false)
+				"house.", true)
 			
 			button1 := basic.NewButton("go inside")
 			button1.OnClick(world.SwitchFunc("inside"))
@@ -78,7 +78,7 @@ func run () {
 				"it is dark, but rays of light stream " +
 				"through the window.\n" +
 				"there is nothing particularly interesting " +
-				"here.", false)
+				"here.", true)
 			
 			button0 := basic.NewButton("go back outside")
 			button0.OnClick(world.SwitchFunc("house"))
@@ -92,7 +92,7 @@ func run () {
 		"bear": func () {
 			label := basic.NewLabel (
 				"you come face to face with a bear.\n" +
-				"it eats you (it was hungry).", false)
+				"it eats you (it was hungry).", true)
 			
 			button0 := basic.NewButton("try again")
 			button0.OnClick(world.SwitchFunc("start"))

examples/horizontalLayout/main.go

@@ -3,7 +3,6 @@ package main
 import "git.tebibyte.media/sashakoshka/tomo"
 import "git.tebibyte.media/sashakoshka/tomo/layouts"
 import "git.tebibyte.media/sashakoshka/tomo/elements/basic"
-import "git.tebibyte.media/sashakoshka/tomo/elements/testing"
 import _ "git.tebibyte.media/sashakoshka/tomo/backends/x"
 
 func main () {
@@ -11,15 +10,15 @@ func main () {
 }
 
 func run () {
-	window, _ := tomo.NewWindow(2, 2)
+	window, _ := tomo.NewWindow(256, 2)
 	window.SetTitle("horizontal stack")
 
 	container := basic.NewContainer(layouts.Horizontal { true, true })
 	window.Adopt(container)
 
-	container.Adopt(testing.NewMouse(), true)
-	container.Adopt(basic.NewLabel("<- left\nright ->", false), false)
-	container.Adopt(testing.NewMouse(), true)
+	container.Adopt(basic.NewLabel("this is sample text", true), true)
+	container.Adopt(basic.NewLabel("this is sample text", true), true)
+	container.Adopt(basic.NewLabel("this is sample text", true), true)
 	
 	window.OnClose(tomo.Stop)
 	window.Show()

examples/label/main.go

@@ -9,7 +9,7 @@ func main () {
 }
 
 func run () {
-	window, _ := tomo.NewWindow(480, 360)
+	window, _ := tomo.NewWindow(480, 2)
 	window.SetTitle("example label")
 	window.Adopt(basic.NewLabel(text, true))
 	window.OnClose(tomo.Stop)

examples/verticalLayout/main.go

@@ -17,7 +17,7 @@ func run () {
 	container := basic.NewContainer(layouts.Vertical { true, true })
 	window.Adopt(container)
 
-	label    := basic.NewLabel("it is a label hehe", false)
+	label    := basic.NewLabel("it is a label hehe", true)
 	button   := basic.NewButton("drawing pad")
 	okButton := basic.NewButton("OK")
 	button.OnClick (func () {

layout.go

@@ -20,8 +20,11 @@ type Layout interface {
 	Arrange (entries []LayoutEntry, width, height int)
 
 	// MinimumSize returns the minimum width and height that the layout
-	// needs to properly arrange the given slice of layout entries, given a
-	// "suqeeze" width so that the height can be determined for elements
-	// fulfilling the Expanding interface.
-	MinimumSize (entries []LayoutEntry, squeeze int) (width, height int)
+	// needs to properly arrange the given slice of layout entries.
+	MinimumSize (entries []LayoutEntry) (width, height int)
+
+	// MinimumHeightFor Returns the minimum height the layout needs to lay
+	// out the specified elements at the given width, taking into account
+	// flexible elements.
+	MinimumHeightFor (entries []LayoutEntry, squeeze int) (height int)
 }

layouts/horizontal.go

@@ -72,7 +72,6 @@ func (layout Horizontal) Arrange (entries []tomo.LayoutEntry, width, height int)
 // arrange the given list of entries.
 func (layout Horizontal) MinimumSize (
 	entries []tomo.LayoutEntry,
-	squeeze int,
 ) (
 	width, height int,
 ) {
@@ -93,3 +92,62 @@ func (layout Horizontal) MinimumSize (
 	}
 	return
 }
+
+func (layout Horizontal) MinimumHeightFor (
+	entries []tomo.LayoutEntry,
+	width int,
+) (
+	height int,
+) {
+	// TODO: maybe put calculating the expanding element width in a separate
+	// method
+	if layout.Pad {
+		width  -= theme.Padding() * 2
+	}
+	freeSpace := width
+	expandingElements := 0
+
+	// count the number of expanding elements and the amount of free space
+	// for them to collectively occupy
+	for index, entry := range entries {
+		if entry.Expand {
+			expandingElements ++
+		} else {
+			entryMinWidth, _ := entry.MinimumSize()
+			freeSpace -= entryMinWidth
+		}
+		if index > 0 && layout.Gap {
+			freeSpace -= theme.Padding()
+		}
+	}
+	expandingElementWidth := 0
+	if expandingElements > 0 {
+		expandingElementWidth = freeSpace / expandingElements
+	}
+	
+	x, y := 0, 0
+	if layout.Pad {
+		x += theme.Padding()
+		y += theme.Padding()
+	}
+
+	// set the size and position of each element
+	for index, entry := range entries {
+		entryWidth, entryHeight := entry.MinimumSize()
+		if entry.Expand {
+			entryWidth = expandingElementWidth
+		}
+		if child, flexible := entry.Element.(tomo.Flexible); flexible {
+			entryHeight = child.MinimumHeightFor(entryWidth)
+		}
+		if entryHeight > height { height = entryHeight }
+		
+		x += entryWidth
+		if index > 0 && layout.Gap { x += theme.Padding() }
+	}
+
+	if layout.Pad {
+		height += theme.Padding() * 2
+	}
+	return
+}

layouts/vertical.go

@@ -26,12 +26,21 @@ func (layout Vertical) Arrange (entries []tomo.LayoutEntry, width, height int) {
 	expandingElements := 0
 
 	// count the number of expanding elements and the amount of free space
-	// for them to collectively occupy
+	// for them to collectively occupy, while gathering minimum heights.
+	minimumHeights := make([]int, len(entries))
 	for index, entry := range entries {
+		var entryMinHeight int
+
+		if child, flexible := entry.Element.(tomo.Flexible); flexible {
+			entryMinHeight = child.MinimumHeightFor(width)
+		} else {
+			_, entryMinHeight = entry.MinimumSize()
+		}
+		minimumHeights[index] = entryMinHeight
+		
 		if entry.Expand {
 			expandingElements ++
 		} else {
-			_, entryMinHeight := entry.MinimumSize()
 			freeSpace -= entryMinHeight
 		}
 		if index > 0 && layout.Gap {
@@ -58,7 +67,7 @@ func (layout Vertical) Arrange (entries []tomo.LayoutEntry, width, height int) {
 		if entry.Expand {
 			entryHeight = expandingElementHeight
 		} else {
-			_, entryHeight = entry.MinimumSize()
+			entryHeight = minimumHeights[index]
 		}
 		y += entryHeight
 		entryBounds := entry.Bounds()
@@ -72,7 +81,6 @@ func (layout Vertical) Arrange (entries []tomo.LayoutEntry, width, height int) {
 // arrange the given list of entries.
 func (layout Vertical) MinimumSize (
 	entries []tomo.LayoutEntry,
-	squeeze int,
 ) (
 	width, height int,
 ) {
@@ -93,3 +101,32 @@ func (layout Vertical) MinimumSize (
 	}
 	return
 }
+
+// MinimumHeightFor Returns the minimum height the layout needs to lay out the
+// specified elements at the given width, taking into account flexible elements.
+func (layout Vertical) MinimumHeightFor (
+	entries []tomo.LayoutEntry,
+	width int,
+) (
+	height int,
+) {
+	if layout.Pad {
+		width -= theme.Padding() * 2
+		height += theme.Padding() * 2
+	}
+	
+	for index, entry := range entries {
+		child, flexible := entry.Element.(tomo.Flexible)
+		if flexible {
+			height += child.MinimumHeightFor(width)
+		} else {
+			_, entryHeight := entry.MinimumSize()
+			height += entryHeight
+		}
+		
+		if layout.Gap && index > 0 {
+			height += theme.Padding()
+		}
+	}
+	return
+}