andlabs-ui/combobox.go

113 lines
2.5 KiB
Go

// 14 february 2014
package ui
import (
"sync"
)
// A Combobox is a drop-down list of items, of which only one can be selected at any given time. You may optionally make the combobox editable to allow custom items.
type Combobox struct {
// TODO Select event
lock sync.Mutex
created bool
sysData *sysData
initItems []string
}
// NewCombobox makes a new combobox with the given items. If editable is true, the combobox is editable.
func NewCombobox(editable bool, items ...string) (c *Combobox) {
c = &Combobox{
sysData: mksysdata(c_combobox),
initItems: items,
}
c.sysData.alternate = editable
return c
}
// Append adds an item to the end of the Combobox's list.
func (c *Combobox) Append(what string) (err error) {
c.lock.Lock()
defer c.lock.Unlock()
if c.created {
return c.sysData.append(what)
}
c.initItems = append(c.initItems, what)
return nil
}
// InsertBefore inserts a new item in the Combobox before the item at the given position.
func (c *Combobox) InsertBefore(what string, before int) (err error) {
c.lock.Lock()
defer c.lock.Unlock()
if c.created {
return c.sysData.insertBefore(what, before)
}
m := make([]string, 0, len(c.initItems) + 1)
m = append(m, c.initItems[:before]...)
m = append(m, what)
c.initItems = append(m, c.initItems[before:]...)
return nil
}
// Delete removes the given item from the Combobox.
func (c *Combobox) Delete(index int) error {
c.lock.Lock()
defer c.lock.Unlock()
if c.created {
return c.sysData.delete(index)
}
c.initItems = append(c.initItems[:index], c.initItems[index + 1:]...)
return nil
}
// Selection returns the current selection.
func (c *Combobox) Selection() string {
c.lock.Lock()
defer c.lock.Unlock()
if c.created {
return c.sysData.text()
}
return ""
}
// SelectedIndex returns the index of the current selection in the Combobox. It returns -1 either if no selection was made or if text was manually entered in an editable Combobox.
func (c *Combobox) SelectedIndex() int {
c.lock.Lock()
defer c.lock.Unlock()
if c.created {
return c.sysData.selectedIndex()
}
return -1
}
func (c *Combobox) make(window *sysData) (err error) {
c.lock.Lock()
defer c.lock.Unlock()
err = c.sysData.make("", window)
if err != nil {
return err
}
for _, s := range c.initItems {
err = c.sysData.append(s)
if err != nil {
return err
}
}
c.created = true
return nil
}
func (c *Combobox) setRect(x int, y int, width int, height int) error {
c.lock.Lock()
defer c.lock.Unlock()
return c.sysData.setRect(x, y, width, height)
}