Started fleshing out the Spinbox interface. Added Value() and SetValue(); implemented on GTK+. Added min and max to the constructor; implemented on GTK+.

basicctrls.go

@@ -143,8 +143,7 @@ func NewTextbox() Textbox {
 // Spinbox is a Control that provides a text entry field that accepts integers and up and down buttons to increment and decrement those values.
 // This control is in its preliminary state.
 // TODO everything:
-// - TODO set increment
-// - TODO set step
+// - TODO set increment? (work on windows)
 // - TODO set page step?
 // - TODO wrapping
 // - TODO set/get integer value
@@ -152,9 +151,19 @@ func NewTextbox() Textbox {
 // - TODO ensuring values entered in text box stay within bounds
 type Spinbox interface {
 	Control
+
+	// Value and SetValue get and set the current value of the Spinbox, respectively.
+	// For SetValue, if the new value is outside the current range of the Spinbox, it is set to the nearest extremity.
+	Value() int
+	SetValue(value int)
 }
 
-// NewSpinbox creates a new Spinbox.
-func NewSpinbox() Spinbox {
-	return newSpinbox()
+// NewSpinbox creates a new Spinbox with the given minimum and maximum.
+// The initial value will be the minimum value.
+// NewSpinbox() panics if min > max.
+func NewSpinbox(min int, max int) Spinbox {
+	if min > max {
+		panic("min > max in NewSpinbox()")
+	}
+	return newSpinbox(min, max)
 }

spinbox_unix.go

@@ -18,8 +18,9 @@ type spinbox struct {
 	spinbutton	*C.GtkSpinButton
 }
 
-func newSpinbox() Spinbox {
-	widget := C.gtk_spin_button_new_with_range(0, 100, 1)
+func newSpinbox(min int, max int) Spinbox {
+	// gtk_spin_button_new_with_range() initially sets its value to the minimum value
+	widget := C.gtk_spin_button_new_with_range(C.gdouble(min), C.gdouble(max), 1)
 	s := &spinbox{
 		controlSingleWidget:	newControlSingleWidget(widget),
 		spinbutton:			(*C.GtkSpinButton)(unsafe.Pointer(widget)),
@@ -28,3 +29,20 @@ func newSpinbox() Spinbox {
 	C.gtk_spin_button_set_numeric(s.spinbutton, C.TRUE)		// digits only
 	return s
 }
+
+func (s *spinbox) Value() int {
+	return int(C.gtk_spin_button_get_value(s.spinbutton))
+}
+
+func (s *spinbox) SetValue(value int) {
+	var min, max C.gdouble
+
+	C.gtk_spin_button_get_range(s.spinbutton, &min, &max)
+	if value < int(min) {
+		value = int(min)
+	}
+	if value > int(max) {
+		value = int(max)
+	}
+	C.gtk_spin_button_set_value(s.spinbutton, C.gdouble(value))
+}

zz_test.go

@@ -149,9 +149,18 @@ func (tw *testwin) addfe() {
 		tw.openbtn, tw.fnlabel)
 	tw.festack.SetStretchy(4)
 	tw.festack.SetStretchy(6)
-	tw.festack2 = newVerticalStack(NewSpinbox(), Space(), NewTextbox())
-	tw.festack2.SetStretchy(1)
-	tw.festack2.SetStretchy(2)
+	sb := NewSpinbox(0, 100)
+	cbutton := NewButton("Set to Invalid Low")
+	cbutton.OnClicked(func() {
+		sb.SetValue(-500)
+	})
+	dbutton := NewButton("Set to Invalid High")
+	dbutton.OnClicked(func() {
+		sb.SetValue(500)
+	})
+	tw.festack2 = newVerticalStack(sb, cbutton, dbutton, Space(), NewTextbox())
+	tw.festack2.SetStretchy(3)
+	tw.festack2.SetStretchy(4)
 	tw.festack = newHorizontalStack(tw.festack, tw.festack2)
 	tw.festack.SetStretchy(0)
 	tw.festack.SetStretchy(1)