Inputs: components 021-030

text_area.go

@@ -0,0 +1,88 @@
+package mujica
+
+import (
+	"fmt"
+	"unicode/utf8"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/theme"
+)
+
+// TextAreaOptions configure a TextArea.
+type TextAreaOptions struct {
+	Placeholder string
+	// Label names the field for assistive technology.
+	Label string
+	// MinHeight is the least height in DIPs; zero fits three lines.
+	MinHeight float32
+	// MaxHeight caps the height in DIPs, then the text scrolls; zero grows freely.
+	MaxHeight float32
+	// MaxLength shows a character count against it; zero hides the count.
+	MaxLength int
+	// SubmitKey with SubmitMods submits; a zero key means Cmd+Enter.
+	SubmitKey  ui.Key
+	SubmitMods ui.Modifiers
+	Disabled   bool
+	ReadOnly   bool
+	// Error marks the value invalid and shows the message below.
+	Error string
+}
+
+// TextArea is a multi-line field editing *value.
+func TextArea(c *ui.Context, value *string, opts TextAreaOptions) InputResult {
+	if value == nil {
+		panic("mujica: TextArea needs a value")
+	}
+	if opts.MinHeight < 0 || opts.MaxHeight < 0 || opts.MaxHeight > 0 && opts.MaxHeight < opts.MinHeight {
+		panic("mujica: TextArea needs 0 <= MinHeight <= MaxHeight")
+	}
+	if opts.MaxLength < 0 {
+		panic("mujica: TextArea MaxLength is negative")
+	}
+	key, mods := opts.SubmitKey, opts.SubmitMods
+	if key == 0 {
+		key, mods = ui.KeyEnter, ui.Cmd
+	}
+	d := Density(c)
+	n := utf8.RuneCountInString(*value)
+	over := opts.MaxLength > 0 && n > opts.MaxLength
+	errMsg := opts.Error
+	if errMsg == "" && over {
+		errMsg = fmt.Sprintf(msg(c, "text_area.over"), n-opts.MaxLength)
+	}
+	count := textAreaCount(c, n, opts.MaxLength)
+	var r InputResult
+	look := &textInputLook{disabled: opts.Disabled, readOnly: opts.ReadOnly, err: errMsg, area: true}
+	r.Element, r.Input = textInputFrame(c, look, func(frame *ui.Element) *ui.Element {
+		in := textInputEditor(c, frame, value, opts.ReadOnly, true).Grow(1).Padding(d.Unit()*2, d.Unit()*3).
+			Placeholder(opts.Placeholder).Label(opts.Label)
+		if opts.MinHeight > 0 {
+			in.MinHeight(opts.MinHeight)
+		}
+		if opts.MaxHeight > 0 {
+			in.MaxHeight(opts.MaxHeight)
+		}
+		r.changed = in.Changed() && !opts.ReadOnly
+		r.submitted = in.Shortcut(mods, key)
+		return in
+	}, count)
+	return r
+}
+
+// textAreaCount builds the character count against max, or nil without one.
+func textAreaCount(c *ui.Context, n, max int) func() {
+	if max == 0 {
+		return nil
+	}
+	return func() {
+		k := Tokens(c)
+		color := k.TextMuted
+		over := n > max
+		if over {
+			color = k.Danger
+		}
+		ui.Text(c, fmt.Sprintf("%d / %d", n, max)).TextColor(color).FontSize(theme.CaptionSize).
+			FontFeatures("tnum").Shrink(0).Label(fmt.Sprintf(msg(c, "text_area.count"), n, max))
+	}
+}