andlabs-ui/group_windows.go

92 lines
2.3 KiB
Go

// 15 august 2014
package ui
import (
"unsafe"
)
// #include "winapi_windows.h"
import "C"
type group struct {
*controlSingleHWNDWithText
child Control
margined bool
}
func newGroup(text string, control Control) Group {
hwnd := C.newControl(buttonclass,
C.BS_GROUPBOX,
C.WS_EX_CONTROLPARENT)
g := &group{
controlSingleHWNDWithText: newControlSingleHWNDWithText(hwnd),
child: control,
}
g.fpreferredSize = g.xpreferredSize
g.fnTabStops = control.nTabStops // groupbox itself is not tabbable but the contents might be
g.SetText(text)
C.controlSetControlFont(g.hwnd)
C.setGroupSubclass(g.hwnd, unsafe.Pointer(g))
control.setParent(&controlParent{g.hwnd})
return g
}
func (g *group) Text() string {
return g.text()
}
func (g *group) SetText(text string) {
g.setText(text)
}
func (g *group) Margined() bool {
return g.margined
}
func (g *group) SetMargined(margined bool) {
g.margined = margined
}
const (
groupXMargin = 6
groupYMarginTop = 11 // note this value /includes the groupbox label/
groupYMarginBottom = 7
)
func (g *group) xpreferredSize(d *sizing) (width, height int) {
var r C.RECT
width, height = g.child.preferredSize(d)
if width < int(g.textlen) { // if the text is longer, try not to truncate
width = int(g.textlen)
}
r.left = 0
r.top = 0
r.right = C.LONG(width)
r.bottom = C.LONG(height)
// use negative numbers to increase the size of the rectangle
if g.margined {
marginRectDLU(&r, -groupYMarginTop, -groupYMarginBottom, -groupXMargin, -groupXMargin, d)
} else {
// unforutnately, as mentioned above, the size of a groupbox includes the label and border
// 1 character cell (4DLU x, 8DLU y) on each side (but only 3DLU on the bottom) should be enough to make up for that; TODO is not, we can change it
// TODO make these named constants
marginRectDLU(&r, -8, -3, -4, -4, d)
}
return int(r.right - r.left), int(r.bottom - r.top)
}
//export groupResized
func groupResized(data unsafe.Pointer, r C.RECT) {
g := (*group)(unsafe.Pointer(data))
d := beginResize(g.hwnd)
if g.margined {
// see above
marginRectDLU(&r, groupYMarginTop, groupYMarginBottom, groupXMargin, groupXMargin, d)
} else {
marginRectDLU(&r, 8, 3, 4, 4, d)
}
g.child.resize(int(r.left), int(r.top), int(r.right - r.left), int(r.bottom - r.top), d)
}