Files
8bitMyGoUI/text/paragraph.go
T

53 lines
1.1 KiB
Go

package text
import (
"fmt"
"github.com/egoist/mygo/ui"
"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
)
type Align uint8
const (
Left Align = iota
Center
Right
)
type ParagraphOptions struct {
// Gap is extra dots between lines.
Gap int
Align Align
MaxLines int
Slot pixel.Slot
}
// Paragraph wraps s at the width it had last frame.
func Paragraph(c *ui.Context, s string, o ParagraphOptions) *ui.Element {
k := pixel.K(c)
gap := pixel.Or("Paragraph Gap", o.Gap, 0)
if o.Align > Right {
panic(fmt.Sprintf("text: unknown Align %d", o.Align))
}
e := ui.Box(c).FillWidth().Label(s).Role(ui.RoleText)
w, check := pixel.WrapWidth(c, e)
lines := pixel.Wrap(s, w, o.MaxLines)
step := pixel.LineHeight + gap
return e.Height(k.D(max(0, len(lines)*step-gap))).Draw(func(p *ui.Painter, r ui.Rect) {
check(r)
g := k.Canvas(p, r)
for i, l := range lines {
x := 0
switch o.Align {
case Center:
x = (g.W - pixel.Measure(l)) / 2
case Right:
x = g.W - pixel.Measure(l)
}
g.Text(x, i*step, l, o.Slot, 1)
}
})
}