objects/textview.go

package objects

import "image"
import "git.tebibyte.media/tomo/tomo"
import "git.tebibyte.media/tomo/tomo/text"
import "git.tebibyte.media/tomo/tomo/event"

var _ tomo.Object = new(TextView)

// TextView is an area for displaying a large amount of multi-line text.
type TextView struct {
	box tomo.TextBox
}

// NewTextView creates a new text view.
func NewTextView (text string) *TextView {
	textView := &TextView { box: tomo.NewTextBox() }
	textView.box.SetRole(tomo.R("objects", "TextView"))
	textView.box.SetFocusable(true)
	textView.box.SetSelectable(true)
	textView.SetText(text)
	textView.box.SetAttr(tomo.AOverflow(false, true))
	textView.box.SetAttr(tomo.AWrap(true))
	textView.box.OnScroll(textView.handleScroll)
	return textView
}

// GetBox returns the underlying box.
func (this *TextView) GetBox () tomo.Box {
	return this.box
}

// SetFocused sets whether or not this text view has keyboard focus. If set to
// true, this method will steal focus away from whichever object currently has
// focus.
func (this *TextView) SetFocused (focused bool) {
	this.box.SetFocused(focused)
}

// Select sets the text cursor or selection.
func (this *TextView) Select (dot text.Dot) {
	this.box.Select(dot)
}

// Dot returns the text cursor or selection.
func (this *TextView) Dot () text.Dot {
	return this.box.Dot()
}

// OnDotChange specifies a function to be called when the text cursor or
// selection changes.
func (this *TextView) OnDotChange (callback func ()) event.Cookie {
	return this.box.OnDotChange(callback)
}

// SetAlign sets the X and Y alignment of the text view.
func (this *TextView) SetAlign (x, y tomo.Align) {
	this.box.SetAttr(tomo.AAlign(x, y))
}

// ContentBounds returns the bounds of the inner content of the text view
// relative to the text view's InnerBounds.
func (this *TextView) ContentBounds () image.Rectangle {
	return this.box.ContentBounds()
}

// ScrollTo shifts the origin of the text view's content to the origin of the
// text view's InnerBounds, offset by the given point.
func (this *TextView) ScrollTo (position image.Point) {
	this.box.ScrollTo(position)
}

// OnContentBoundsChange specifies a function to be called when the text view's
// ContentBounds or InnerBounds changes.
func (this *TextView) OnContentBoundsChange (callback func ()) event.Cookie {
	return this.box.OnContentBoundsChange(callback)
}

// SetText sets the text content of the view.
func (this *TextView) SetText (text string) {
	this.box.SetText(text)
}

func (this *TextView) handleScroll (x, y float64) bool {
	this.ScrollTo(this.ContentBounds().Min.Sub(image.Pt(int(x), int(y))))
	return true
}