diff --git a/widget/button.go b/widget/button.go index 95655e06..d955d693 100644 --- a/widget/button.go +++ b/widget/button.go @@ -18,9 +18,7 @@ import ( // Clickable represents a clickable area. type Clickable struct { - click gesture.Click - // clicks is for saved clicks to support Clicked. - clicks []Click + click gesture.Click history []Press keyTag struct{} @@ -53,19 +51,10 @@ func (b *Clickable) Click() { b.requestClicks++ } -// Clicked reports whether there are pending clicks. If so, Clicked -// removes the earliest click. +// Clicked calls Update and reports whether a click was registered. func (b *Clickable) Clicked(gtx layout.Context) bool { - if len(b.clicks) > 0 { - b.clicks = b.clicks[1:] - return true - } - b.clicks = b.Update(gtx) - if len(b.clicks) > 0 { - b.clicks = b.clicks[1:] - return true - } - return false + _, clicked := b.Update(gtx) + return clicked } // Hovered reports whether a pointer is over the element. @@ -96,7 +85,12 @@ func (b *Clickable) History() []Press { // Layout and update the button state. func (b *Clickable) Layout(gtx layout.Context, w layout.Widget) layout.Dimensions { - b.Update(gtx) + for { + _, ok := b.Update(gtx) + if !ok { + break + } + } m := op.Record(gtx.Ops) dims := w(gtx) c := m.Stop() @@ -108,10 +102,9 @@ func (b *Clickable) Layout(gtx layout.Context, w layout.Widget) layout.Dimension return dims } -// Update the button state by processing events, and return the resulting -// clicks, if any. -func (b *Clickable) Update(gtx layout.Context) []Click { - b.clicks = nil +// Update the button state by processing events, and return the next +// click, if any. +func (b *Clickable) Update(gtx layout.Context) (Click, bool) { if !gtx.Enabled() { b.focused = false } @@ -123,12 +116,11 @@ func (b *Clickable) Update(gtx layout.Context) []Click { n := copy(b.history, b.history[1:]) b.history = b.history[:n] } - var clicks []Click if c := b.requestClicks; c > 0 { b.requestClicks = 0 - clicks = append(clicks, Click{ + return Click{ NumClicks: c, - }) + }, true } for _, e := range b.click.Update(gtx.Source) { switch e.Kind { @@ -136,10 +128,10 @@ func (b *Clickable) Update(gtx layout.Context) []Click { if l := len(b.history); l > 0 { b.history[l-1].End = gtx.Now } - clicks = append(clicks, Click{ + return Click{ Modifiers: e.Modifiers, NumClicks: e.NumClicks, - }) + }, true case gesture.KindCancel: for i := range b.history { b.history[i].Cancelled = true @@ -190,12 +182,12 @@ func (b *Clickable) Update(gtx layout.Context) []Click { } // only register a key as a click if the key was pressed and released while this button was focused b.pressedKey = "" - clicks = append(clicks, Click{ + return Click{ Modifiers: e.Modifiers, NumClicks: 1, - }) + }, true } } } - return clicks + return Click{}, false }