andlabs-ui/colorbutton.go

84 lines
2.2 KiB
Go

// 12 december 2015
package ui
import (
"unsafe"
)
// #include <stdlib.h>
// #include "ui.h"
// #include "util.h"
// extern void doColorButtonOnChanged(uiColorButton *, void *);
// // see golang/go#19835
// typedef void (*colorButtonCallback)(uiColorButton *, void *);
// typedef struct pkguiCColor pkguiCColor;
// struct pkguiCColor { double *r; double *g; double *b; double *a; };
// static inline pkguiCColor pkguiNewCColor(void)
// {
// pkguiCColor c;
//
// c.r = (double *) pkguiAlloc(4 * sizeof (double));
// c.g = c.r + 1;
// c.b = c.g + 1;
// c.a = c.b + 1;
// return c;
// }
// static inline void pkguiFreeCColor(pkguiCColor c)
// {
// free(c.r);
// }
import "C"
// ColorButton is a Control that represents a button that the user can
// click to select a color.
type ColorButton struct {
ControlBase
b *C.uiColorButton
onChanged func(*ColorButton)
}
// NewColorButton creates a new ColorButton.
func NewColorButton() *ColorButton {
b := new(ColorButton)
b.b = C.uiNewColorButton()
C.uiColorButtonOnChanged(b.b, C.colorButtonCallback(C.doColorButtonOnChanged), nil)
b.ControlBase = NewControlBase(b, uintptr(unsafe.Pointer(b.b)))
return b
}
// Color returns the color currently selected in the ColorButton.
// Colors are not alpha-premultiplied.
// TODO rename b or bl
func (b *ColorButton) Color() (r, g, bl, a float64) {
c := C.pkguiNewCColor()
defer C.pkguiFreeCColor(c)
C.uiColorButtonColor(b.b, c.r, c.g, c.b, c.a)
return float64(*(c.r)), float64(*(c.g)), float64(*(c.b)), float64(*(c.a))
}
// SetColor sets the currently selected color in the ColorButton.
// Colors are not alpha-premultiplied.
// TODO rename b or bl
func (b *ColorButton) SetColor(r, g, bl, a float64) {
C.uiColorButtonSetColor(b.b, C.double(r), C.double(g), C.double(bl), C.double(a))
}
// OnChanged registers f to be run when the user changes the
// currently selected color in the ColorButton. Only one function
// can be registered at a time.
func (b *ColorButton) OnChanged(f func(*ColorButton)) {
b.onChanged = f
}
//export doColorButtonOnChanged
func doColorButtonOnChanged(bb *C.uiColorButton, data unsafe.Pointer) {
b := ControlFromLibui(uintptr(unsafe.Pointer(bb))).(*ColorButton)
if b.onChanged != nil {
b.onChanged(b)
}
}