Add documentation for Slider

scrollbar.go

@@ -80,6 +80,13 @@ func (this *Scrollbar) SetValue (value float64) {
 // right/bottom.
 func (this *Scrollbar) Value () float64 {
 	// TODO
+	return 0
+}
+
+// OnValueChange specifies a function to be called when the position of the
+// scrollbar changes.
+func (this *Slider) OnValueChange (callback func ()) event.Cookie {
+	return this.on.valueChange.Connect(callback)
 }
 
 func (this *Scrollbar) handleKeyDown (key input.Key, numpad bool) {

slider.go

@@ -6,6 +6,7 @@ import "git.tebibyte.media/tomo/tomo/theme"
 import "git.tebibyte.media/tomo/tomo/input"
 import "git.tebibyte.media/tomo/tomo/event"
 
+// Slider is a control that selects a numeric value between 0 and 1.
 type Slider struct {
 	tomo.ContainerBox
 	handle     *SliderHandle
@@ -18,6 +19,8 @@ type Slider struct {
 	}
 }
 
+// SliderHandle is a simple object that serves as a handle for sliders and
+// scrollbars. It is completely inert.
 type SliderHandle struct {
 	tomo.Box
 }
@@ -51,14 +54,17 @@ func newSlider (orient string, value float64) *Slider {
 	return this
 }
 
+// NewVerticalSlider creates a new vertical slider with the specified value.
 func NewVerticalSlider (value float64) *Slider {
 	return newSlider("vertical", value)
 }
 
+// NewHorizontalSlider creates a new horizontal slider with the specified value.
 func NewHorizontalSlider (value float64) *Slider {
 	return newSlider("horizontal", value)
 }
 
+// SetValue sets the value of the slider between 0 and 1.
 func (this *Slider) SetValue (value float64) {
 	if value < 0 { value = 0 }
 	if value > 1 { value = 1 }
@@ -68,10 +74,13 @@ func (this *Slider) SetValue (value float64) {
 	this.on.valueChange.Broadcast()
 }
 
+// Value returns the value of the slider between 0 and 1.
 func (this *Slider) Value () float64 {
 	return this.layout.value
 }
 
+// OnValueChange specifies a function to be called when the slider's value
+// changes.
 func (this *Slider) OnValueChange (callback func ()) event.Cookie {
 	return this.on.valueChange.Connect(callback)
 }