tcell/views/textarea.go

156 lines
3.4 KiB
Go

// Copyright 2016 The Tcell Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use file except in compliance with the License.
// You may obtain a copy of the license at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package views
import (
"strings"
"sync"
"github.com/gdamore/tcell/v2"
)
// TextArea is a pannable 2 dimensional text widget. It wraps both
// the view and the model for text in a single, convenient widget.
// Text is provided as an array of strings, each of which represents
// a single line to display. All text in the TextArea has the same
// style. An optional soft cursor is available.
type TextArea struct {
model *linesModel
once sync.Once
CellView
}
type linesModel struct {
runes [][]rune
width int
height int
x int
y int
hide bool
cursor bool
style tcell.Style
}
func (m *linesModel) GetCell(x, y int) (rune, tcell.Style, []rune, int) {
if x < 0 || y < 0 || y >= m.height || x >= len(m.runes[y]) {
return 0, m.style, nil, 1
}
// XXX: extend this to support combining and full width chars
return m.runes[y][x], m.style, nil, 1
}
func (m *linesModel) GetBounds() (int, int) {
return m.width, m.height
}
func (m *linesModel) limitCursor() {
if m.x > m.width-1 {
m.x = m.width - 1
}
if m.y > m.height-1 {
m.y = m.height - 1
}
if m.x < 0 {
m.x = 0
}
if m.y < 0 {
m.y = 0
}
}
func (m *linesModel) SetCursor(x, y int) {
m.x = x
m.y = y
m.limitCursor()
}
func (m *linesModel) MoveCursor(x, y int) {
m.x += x
m.y += y
m.limitCursor()
}
func (m *linesModel) GetCursor() (int, int, bool, bool) {
return m.x, m.y, m.cursor, !m.hide
}
// SetLines sets the content text to display.
func (ta *TextArea) SetLines(lines []string) {
ta.Init()
m := ta.model
m.width = 0
// extend slice before using m.runes[row] to avoid panic
slice := make([][]rune, len(lines))
m.runes = slice
for row, line := range lines {
for _, ch := range line {
m.runes[row] = append(m.runes[row], ch)
}
if len(m.runes[row]) > m.width {
m.width = len(m.runes[row])
}
}
m.height = len(m.runes)
ta.CellView.SetModel(m)
}
func (ta *TextArea) SetStyle(style tcell.Style) {
ta.model.style = style
ta.CellView.SetStyle(style)
}
// EnableCursor enables a soft cursor in the TextArea.
func (ta *TextArea) EnableCursor(on bool) {
ta.Init()
ta.model.cursor = on
}
// HideCursor hides or shows the cursor in the TextArea.
// If on is true, the cursor is hidden. Note that a cursor is only
// shown if it is enabled.
func (ta *TextArea) HideCursor(on bool) {
ta.Init()
ta.model.hide = on
}
// SetContent is used to set the textual content, passed as a
// single string. Lines within the string are delimited by newlines.
func (ta *TextArea) SetContent(text string) {
ta.Init()
lines := strings.Split(strings.Trim(text, "\n"), "\n")
ta.SetLines(lines)
}
// Init initializes the TextArea.
func (ta *TextArea) Init() {
ta.once.Do(func() {
lm := &linesModel{runes: [][]rune{}, width: 0}
ta.model = lm
ta.CellView.Init()
ta.CellView.SetModel(lm)
})
}
// NewTextArea creates a blank TextArea.
func NewTextArea() *TextArea {
ta := &TextArea{}
ta.Init()
return ta
}