io/system: remove resize actions

Allowing clients to initiate resize gestures is a waste: macOS
doesn't support them, and the only reason we added them was to
implement client-side decorations for Wayland. Now all desktop
platforms implement resize gestures as needed, and we no longer
need the system.Action actions.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/window.go

@@ -983,11 +983,7 @@ func (w *Window) decorate(d driver, e system.FrameEvent, o *op.Ops) (size, offse
 		w.decorations.Decorations = deco
 	}
 	allActions := system.ActionMinimize | system.ActionMaximize | system.ActionUnmaximize |
-		system.ActionClose | system.ActionMove |
+		system.ActionClose | system.ActionMove
-		system.ActionResizeNorth | system.ActionResizeSouth |
-		system.ActionResizeWest | system.ActionResizeEast |
-		system.ActionResizeNorthWest | system.ActionResizeSouthWest |
-		system.ActionResizeNorthEast | system.ActionResizeSouthEast
 	style := material.Decorations(theme, deco, allActions, w.decorations.Config.Title)
 	// Update the decorations based on the current window mode.
 	var actions system.Action

io/system/decoration.go

@@ -2,8 +2,6 @@ package system
 
 import (
 	"strings"
-
-	"gioui.org/io/pointer"
 )
 
 // Action is a set of window decoration actions.
@@ -31,49 +29,8 @@ const (
 	ActionClose
 	// ActionMove moves a window directed by the user.
 	ActionMove
-	// ActionResizeNorth resizes the top border of a window (directed by the user).
-	ActionResizeNorth
-	// ActionResizeSouth resizes the bottom border of a window (directed by the user).
-	ActionResizeSouth
-	// ActionResizeWest resizes the right border of a window (directed by the user).
-	ActionResizeWest
-	// ActionResizeEast resizes the left border of a window (directed by the user).
-	ActionResizeEast
-	// ActionResizeNorthWest resizes the top-left corner of a window (directed by the user).
-	ActionResizeNorthWest
-	// ActionResizeSouthWest resizes the bottom-left corner of a window (directed by the user).
-	ActionResizeSouthWest
-	// ActionResizeNorthEast resizes the top-right corner of a window (directed by the user).
-	ActionResizeNorthEast
-	// ActionResizeSouthEast resizes the bottom-right corner of a window (directed by the user).
-	ActionResizeSouthEast
 )
 
-// Cursor returns the cursor for the action.
-// It must be a single action otherwise the default
-// cursor is returned.
-func (a Action) Cursor() pointer.Cursor {
-	switch a {
-	case ActionResizeNorthWest:
-		return pointer.CursorNorthWestResize
-	case ActionResizeSouthEast:
-		return pointer.CursorSouthEastResize
-	case ActionResizeNorthEast:
-		return pointer.CursorNorthEastResize
-	case ActionResizeSouthWest:
-		return pointer.CursorSouthWestResize
-	case ActionResizeWest:
-		return pointer.CursorWestResize
-	case ActionResizeEast:
-		return pointer.CursorEastResize
-	case ActionResizeNorth:
-		return pointer.CursorNorthResize
-	case ActionResizeSouth:
-		return pointer.CursorSouthResize
-	}
-	return pointer.CursorDefault
-}
-
 func (a Action) String() string {
 	var buf strings.Builder
 	for b := Action(1); a != 0; b <<= 1 {
@@ -100,22 +57,6 @@ func (a Action) string() string {
 		return "ActionClose"
 	case ActionMove:
 		return "ActionMove"
-	case ActionResizeNorth:
-		return "ActionResizeNorth"
-	case ActionResizeSouth:
-		return "ActionResizeSouth"
-	case ActionResizeWest:
-		return "ActionResizeWest"
-	case ActionResizeEast:
-		return "ActionResizeEast"
-	case ActionResizeNorthWest:
-		return "ActionResizeNorthWest"
-	case ActionResizeSouthWest:
-		return "ActionResizeSouthWest"
-	case ActionResizeNorthEast:
-		return "ActionResizeNorthEast"
-	case ActionResizeSouthEast:
-		return "ActionResizeSouthEast"
 	}
 	return ""
 }

widget/decorations.go

@@ -2,11 +2,9 @@ package widget
 
 import (
 	"fmt"
-	"image"
 	"math/bits"
 
 	"gioui.org/gesture"
-	"gioui.org/io/pointer"
 	"gioui.org/io/system"
 	"gioui.org/layout"
 	"gioui.org/op/clip"
@@ -63,45 +61,6 @@ func (d *Decorations) Clickable(action system.Action) *Clickable {
 	return click
 }
 
-// LayoutResize lays out the resize actions.
-func (d *Decorations) LayoutResize(gtx layout.Context, actions system.Action) {
-	cs := gtx.Constraints.Max
-	wh := gtx.Dp(10)
-	s := []struct {
-		system.Action
-		image.Rectangle
-	}{
-		{system.ActionResizeNorth, image.Rect(0, 0, cs.X, wh)},
-		{system.ActionResizeSouth, image.Rect(0, cs.Y-wh, cs.X, cs.Y)},
-		{system.ActionResizeWest, image.Rect(cs.X-wh, 0, cs.X, cs.Y)},
-		{system.ActionResizeEast, image.Rect(0, 0, wh, cs.Y)},
-		{system.ActionResizeNorthWest, image.Rect(0, 0, wh, wh)},
-		{system.ActionResizeNorthEast, image.Rect(cs.X-wh, 0, cs.X, wh)},
-		{system.ActionResizeSouthWest, image.Rect(0, cs.Y-wh, wh, cs.Y)},
-		{system.ActionResizeSouthEast, image.Rect(cs.X-wh, cs.Y-wh, cs.X, cs.Y)},
-	}
-	for i, data := range s {
-		action := data.Action
-		if actions&action == 0 {
-			continue
-		}
-		rsz := &d.resize[i]
-		rsz.Events(gtx.Metric, gtx, gesture.Both)
-		if rsz.Drag.Dragging() {
-			d.actions |= action
-		}
-		st := clip.Rect(data.Rectangle).Push(gtx.Ops)
-		if rsz.Hover.Hovered(gtx) {
-			action.Cursor().Add(gtx.Ops)
-		}
-		rsz.Drag.Add(gtx.Ops)
-		pass := pointer.PassOp{}.Push(gtx.Ops)
-		rsz.Hover.Add(gtx.Ops)
-		pass.Pop()
-		st.Pop()
-	}
-}
-
 // Perform updates the decorations as if the specified actions were
 // performed by the user.
 func (d *Decorations) Perform(actions system.Action) {

widget/material/decorations.go

@@ -45,9 +45,6 @@ func (d DecorationsStyle) Layout(gtx layout.Context) layout.Dimensions {
 	r := clip.Rect{Max: dims.Size}
 	paint.FillShape(gtx.Ops, d.Background, r.Op())
 	decos.Add(gtx.Ops)
-	if !d.Decorations.Maximized() {
-		d.Decorations.LayoutResize(gtx, d.Actions)
-	}
 	return dims
 }