forked from fyne-io/fyne
/
canvas.go
527 lines (441 loc) · 13 KB
/
canvas.go
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package gomobile
import (
"context"
"image"
"math"
"time"
"fyne.io/fyne"
"fyne.io/fyne/driver/mobile"
"fyne.io/fyne/internal"
"fyne.io/fyne/internal/app"
"fyne.io/fyne/internal/cache"
"fyne.io/fyne/internal/driver"
"fyne.io/fyne/internal/painter/gl"
"fyne.io/fyne/theme"
"fyne.io/fyne/widget"
)
type mobileCanvas struct {
content fyne.CanvasObject
windowHead, menu fyne.CanvasObject
overlays *internal.OverlayStack
painter gl.Painter
scale float32
size fyne.Size
focused fyne.Focusable
touched map[int]mobile.Touchable
padded bool
onTypedRune func(rune)
onTypedKey func(event *fyne.KeyEvent)
shortcut fyne.ShortcutHandler
inited bool
lastTapDown map[int]time.Time
lastTapDownPos map[int]fyne.Position
dragging fyne.Draggable
refreshQueue chan fyne.CanvasObject
minSizeCache map[fyne.CanvasObject]fyne.Size
touchTapCount int
touchCancelFunc context.CancelFunc
touchLastTapped fyne.CanvasObject
}
const (
doubleClickDelay = 500 // ms (maximum interval between clicks for double click detection)
)
func (c *mobileCanvas) Content() fyne.CanvasObject {
return c.content
}
func (c *mobileCanvas) SetContent(content fyne.CanvasObject) {
c.content = content
c.sizeContent(c.Size().Union(content.MinSize()))
}
// Deprecated: Use Overlays() instead.
func (c *mobileCanvas) Overlay() fyne.CanvasObject {
return c.overlays.Top()
}
func (c *mobileCanvas) Overlays() fyne.OverlayStack {
return c.overlays
}
// Deprecated: Use Overlays() instead.
func (c *mobileCanvas) SetOverlay(overlay fyne.CanvasObject) {
if len(c.overlays.List()) > 0 {
c.overlays.Remove(c.overlays.List()[0])
}
c.overlays.Add(overlay)
}
func (c *mobileCanvas) Refresh(obj fyne.CanvasObject) {
select {
case c.refreshQueue <- obj:
// all good
default:
// queue is full, ignore
}
}
func (c *mobileCanvas) edgePadding() (topLeft, bottomRight fyne.Size) {
scale := fyne.CurrentDevice().SystemScaleForWindow(nil) // we don't need a window parameter on mobile
dev, ok := fyne.CurrentDevice().(*device)
if !ok {
return fyne.NewSize(0, 0), fyne.NewSize(0, 0) // running in test mode
}
return fyne.NewSize(int(float32(dev.insetLeft)/scale), int(float32(dev.insetTop)/scale)),
fyne.NewSize(int(float32(dev.insetRight)/scale), int(float32(dev.insetBottom)/scale))
}
func (c *mobileCanvas) sizeContent(size fyne.Size) {
if c.content == nil { // window may not be configured yet
return
}
offset := fyne.NewPos(0, 0)
devicePadTopLeft, devicePadBottomRight := c.edgePadding()
if c.windowHead != nil {
topHeight := c.windowHead.MinSize().Height
if len(c.windowHead.(*widget.Box).Children) > 1 {
c.windowHead.Resize(fyne.NewSize(size.Width-devicePadTopLeft.Width-devicePadBottomRight.Width, topHeight))
offset = fyne.NewPos(0, topHeight)
} else {
c.windowHead.Resize(c.windowHead.MinSize())
}
c.windowHead.Move(fyne.NewPos(devicePadTopLeft.Width, devicePadTopLeft.Height))
}
innerSize := size.Subtract(devicePadTopLeft).Subtract(devicePadBottomRight)
topLeft := offset.Add(fyne.NewPos(devicePadTopLeft.Width, devicePadTopLeft.Height))
c.size = size
if c.padded {
c.content.Resize(innerSize.Subtract(fyne.NewSize(theme.Padding()*2, theme.Padding()*2)))
c.content.Move(topLeft.Add(fyne.NewPos(theme.Padding(), theme.Padding())))
} else {
c.content.Resize(innerSize)
c.content.Move(topLeft)
}
}
func (c *mobileCanvas) resize(size fyne.Size) {
if size == c.size {
return
}
c.sizeContent(size)
}
func (c *mobileCanvas) Focus(obj fyne.Focusable) {
if c.focused == obj || obj == nil {
return
}
if dis, ok := obj.(fyne.Disableable); ok && dis.Disabled() {
c.Unfocus()
return
}
if c.focused != nil {
c.focused.FocusLost()
}
c.focused = obj
obj.FocusGained()
if keyb, ok := obj.(mobile.Keyboardable); ok {
showVirtualKeyboard(keyb.Keyboard())
} else {
hideVirtualKeyboard()
}
}
func (c *mobileCanvas) Unfocus() {
if c.focused != nil {
c.focused.FocusLost()
hideVirtualKeyboard()
}
c.focused = nil
}
func (c *mobileCanvas) Focused() fyne.Focusable {
return c.focused
}
func (c *mobileCanvas) Size() fyne.Size {
return c.size
}
func (c *mobileCanvas) Scale() float32 {
return c.scale
}
// Deprecated: Settings are now calculated solely on the user configuration and system setup.
func (c *mobileCanvas) SetScale(_ float32) {
c.scale = fyne.CurrentDevice().SystemScaleForWindow(nil) // we don't need a window parameter on mobile
}
func (c *mobileCanvas) PixelCoordinateForPosition(pos fyne.Position) (int, int) {
return int(float32(pos.X) * c.scale), int(float32(pos.Y) * c.scale)
}
func (c *mobileCanvas) OnTypedRune() func(rune) {
return c.onTypedRune
}
func (c *mobileCanvas) SetOnTypedRune(typed func(rune)) {
c.onTypedRune = typed
}
func (c *mobileCanvas) OnTypedKey() func(*fyne.KeyEvent) {
return c.onTypedKey
}
func (c *mobileCanvas) SetOnTypedKey(typed func(*fyne.KeyEvent)) {
c.onTypedKey = typed
}
func (c *mobileCanvas) AddShortcut(shortcut fyne.Shortcut, handler func(shortcut fyne.Shortcut)) {
c.shortcut.AddShortcut(shortcut, handler)
}
func (c *mobileCanvas) RemoveShortcut(shortcut fyne.Shortcut) {
c.shortcut.RemoveShortcut(shortcut)
}
func (c *mobileCanvas) Capture() image.Image {
return c.painter.Capture(c)
}
func (c *mobileCanvas) minSizeChanged() bool {
if c.Content() == nil {
return false
}
minSizeChange := false
ensureMinSize := func(obj, parent fyne.CanvasObject) {
if !obj.Visible() {
return
}
minSize := obj.MinSize()
if minSize != c.minSizeCache[obj] {
minSizeChange = true
c.minSizeCache[obj] = minSize
}
}
c.walkTree(nil, ensureMinSize)
return minSizeChange
}
func (c *mobileCanvas) ensureMinSize() {
if c.Content() == nil {
return
}
var lastParent fyne.CanvasObject
ensureMinSize := func(obj, parent fyne.CanvasObject) {
if !obj.Visible() {
return
}
minSize := obj.MinSize()
objToLayout := obj
if parent != nil {
objToLayout = parent
} else {
size := obj.Size()
expectedSize := minSize.Union(size)
if expectedSize != size && size != c.size {
objToLayout = nil
obj.Resize(expectedSize)
}
}
if objToLayout != lastParent {
updateLayout(lastParent)
lastParent = objToLayout
}
}
c.walkTree(nil, ensureMinSize)
if lastParent != nil {
updateLayout(lastParent)
}
}
func updateLayout(objToLayout fyne.CanvasObject) {
switch cont := objToLayout.(type) {
case *fyne.Container:
if cont.Layout != nil {
cont.Layout.Layout(cont.Objects, cont.Size())
}
case fyne.Widget:
cache.Renderer(cont).Layout(cont.Size())
}
}
func (c *mobileCanvas) objectTrees() []fyne.CanvasObject {
trees := make([]fyne.CanvasObject, 0, len(c.Overlays().List())+2)
trees = append(trees, c.content)
if c.menu != nil {
trees = append(trees, c.menu)
}
trees = append(trees, c.Overlays().List()...)
return trees
}
func (c *mobileCanvas) walkTree(
beforeChildren func(fyne.CanvasObject, fyne.Position, fyne.Position, fyne.Size) bool,
afterChildren func(fyne.CanvasObject, fyne.CanvasObject),
) {
driver.WalkVisibleObjectTree(c.content, beforeChildren, afterChildren)
if c.windowHead != nil {
driver.WalkVisibleObjectTree(c.windowHead, beforeChildren, afterChildren)
}
if c.menu != nil {
driver.WalkVisibleObjectTree(c.menu, beforeChildren, afterChildren)
}
for _, overlay := range c.overlays.List() {
if overlay != nil {
driver.WalkVisibleObjectTree(overlay, beforeChildren, afterChildren)
}
}
}
func (c *mobileCanvas) findObjectAtPositionMatching(pos fyne.Position, test func(object fyne.CanvasObject) bool) (fyne.CanvasObject, fyne.Position, int) {
if c.menu != nil {
return driver.FindObjectAtPositionMatching(pos, test, c.overlays.Top(), c.menu)
}
return driver.FindObjectAtPositionMatching(pos, test, c.overlays.Top(), c.windowHead, c.content)
}
func (c *mobileCanvas) tapDown(pos fyne.Position, tapID int) {
c.lastTapDown[tapID] = time.Now()
c.lastTapDownPos[tapID] = pos
c.dragging = nil
co, objPos, layer := c.findObjectAtPositionMatching(pos, func(object fyne.CanvasObject) bool {
switch object.(type) {
case fyne.Tappable, mobile.Touchable, fyne.Focusable:
return true
}
return false
})
if wid, ok := co.(mobile.Touchable); ok {
touchEv := &mobile.TouchEvent{}
touchEv.Position = objPos
touchEv.AbsolutePosition = pos
wid.TouchDown(touchEv)
c.touched[tapID] = wid
}
if layer != 1 { // 0 - overlay, 1 - window head / menu, 2 - content
if wid, ok := co.(fyne.Focusable); ok {
c.Focus(wid)
} else {
c.Unfocus()
}
}
}
func (c *mobileCanvas) tapMove(pos fyne.Position, tapID int,
dragCallback func(fyne.Draggable, *fyne.DragEvent)) {
deltaX := pos.X - c.lastTapDownPos[tapID].X
deltaY := pos.Y - c.lastTapDownPos[tapID].Y
if math.Abs(float64(deltaX)) < 3 && math.Abs(float64(deltaY)) < 3 {
return
}
c.lastTapDownPos[tapID] = pos
co, objPos, _ := c.findObjectAtPositionMatching(pos, func(object fyne.CanvasObject) bool {
if _, ok := object.(fyne.Draggable); ok {
return true
} else if _, ok := object.(mobile.Touchable); ok {
return true
}
return false
})
if c.touched[tapID] != nil {
if touch, ok := co.(mobile.Touchable); !ok || c.touched[tapID] != touch {
touchEv := &mobile.TouchEvent{}
touchEv.Position = objPos
touchEv.AbsolutePosition = pos
c.touched[tapID].TouchCancel(touchEv)
c.touched[tapID] = nil
}
}
if c.dragging == nil {
if drag, ok := co.(fyne.Draggable); ok {
c.dragging = drag
} else {
return
}
}
ev := new(fyne.DragEvent)
ev.Position = objPos
ev.DraggedX = deltaX
ev.DraggedY = deltaY
dragCallback(c.dragging, ev)
}
func (c *mobileCanvas) tapUp(pos fyne.Position, tapID int,
tapCallback func(fyne.Tappable, *fyne.PointEvent),
tapAltCallback func(fyne.SecondaryTappable, *fyne.PointEvent),
doubleTapCallback func(fyne.DoubleTappable, *fyne.PointEvent),
dragCallback func(fyne.Draggable, *fyne.DragEvent)) {
if c.dragging != nil {
c.dragging.DragEnd()
c.dragging = nil
return
}
duration := time.Since(c.lastTapDown[tapID])
if c.menu != nil && c.overlays.Top() == nil && pos.X > c.menu.Size().Width {
c.menu.Hide()
c.menu.Refresh()
c.menu = nil
return
}
co, objPos, _ := c.findObjectAtPositionMatching(pos, func(object fyne.CanvasObject) bool {
if _, ok := object.(fyne.Tappable); ok {
return true
} else if _, ok := object.(fyne.SecondaryTappable); ok {
return true
} else if _, ok := object.(mobile.Touchable); ok {
return true
} else if _, ok := object.(fyne.Focusable); ok {
return true
} else if _, ok := object.(fyne.DoubleTappable); ok {
return true
}
return false
})
if wid, ok := co.(mobile.Touchable); ok {
touchEv := &mobile.TouchEvent{}
touchEv.Position = objPos
touchEv.AbsolutePosition = pos
wid.TouchUp(touchEv)
c.touched[tapID] = nil
}
ev := new(fyne.PointEvent)
ev.Position = objPos
ev.AbsolutePosition = pos
// TODO move event queue to common code w.queueEvent(func() { wid.Tapped(ev) })
if duration < tapSecondaryDelay {
_, doubleTap := co.(fyne.DoubleTappable)
if doubleTap {
c.touchTapCount++
c.touchLastTapped = co
if c.touchCancelFunc != nil {
c.touchCancelFunc()
return
}
go c.waitForDoubleTap(co, ev, tapCallback, doubleTapCallback)
} else {
if wid, ok := co.(fyne.Tappable); ok {
tapCallback(wid, ev)
}
}
} else {
if wid, ok := co.(fyne.SecondaryTappable); ok {
tapAltCallback(wid, ev)
}
}
}
func (c *mobileCanvas) waitForDoubleTap(co fyne.CanvasObject, ev *fyne.PointEvent, tapCallback func(fyne.Tappable, *fyne.PointEvent), doubleTapCallback func(fyne.DoubleTappable, *fyne.PointEvent)) {
var ctx context.Context
ctx, c.touchCancelFunc = context.WithDeadline(context.TODO(), time.Now().Add(time.Millisecond*doubleClickDelay))
defer c.touchCancelFunc()
<-ctx.Done()
if c.touchTapCount == 2 && c.touchLastTapped == co {
if wid, ok := co.(fyne.DoubleTappable); ok {
doubleTapCallback(wid, ev)
}
} else {
if wid, ok := co.(fyne.Tappable); ok {
tapCallback(wid, ev)
}
}
c.touchTapCount = 0
c.touchCancelFunc = nil
c.touchLastTapped = nil
return
}
func (c *mobileCanvas) setupThemeListener() {
listener := make(chan fyne.Settings)
fyne.CurrentApp().Settings().AddChangeListener(listener)
go func() {
for {
<-listener
if c.menu != nil {
app.ApplyThemeTo(c.menu, c) // Ensure our menu gets the theme change message as it's out-of-tree
}
if c.windowHead != nil {
app.ApplyThemeTo(c.windowHead, c) // Ensure our child windows get the theme change message as it's out-of-tree
}
}
}()
}
// NewCanvas creates a new gomobile mobileCanvas. This is a mobileCanvas that will render on a mobile device using OpenGL.
func NewCanvas() fyne.Canvas {
ret := &mobileCanvas{padded: true}
ret.scale = fyne.CurrentDevice().SystemScaleForWindow(nil) // we don't need a window parameter on mobile
ret.refreshQueue = make(chan fyne.CanvasObject, 1024)
ret.touched = make(map[int]mobile.Touchable)
ret.lastTapDownPos = make(map[int]fyne.Position)
ret.lastTapDown = make(map[int]time.Time)
ret.minSizeCache = make(map[fyne.CanvasObject]fyne.Size)
ret.overlays = &internal.OverlayStack{}
ret.setupThemeListener()
return ret
}