andlabs-ui/group_windows.go

99 lines
2.6 KiB
Go

// 15 august 2014
package ui
// #include "winapi_windows.h"
import "C"
type group struct {
*controlSingleHWNDWithText
child Control
margined bool
chainresize func(x int, y int, width int, height int, d *sizing)
}
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.chainresize = g.fresize
g.fresize = g.xresize
g.fnTabStops = control.nTabStops // groupbox itself is not tabbable but the contents might be
g.SetText(text)
C.controlSetControlFont(g.hwnd)
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
// 1DLU on each side should be enough to make up for that; TODO is not, we can change it
// TODO make these named constants
marginRectDLU(&r, -1, -1, -1, -1, d)
}
return int(r.right - r.left), int(r.bottom - r.top)
}
func (g *group) xresize(x int, y int, width int, height int, d *sizing) {
// first, chain up to the container base to keep the Z-order correct
g.chainresize(x, y, width, height, d)
// now resize the child container
var r C.RECT
// pretend that the client area of the group box only includes the actual empty space
// container will handle the necessary adjustments properly
r.left = 0
r.top = 0
r.right = C.LONG(width)
r.bottom = C.LONG(height)
if g.margined {
// see above
marginRectDLU(&r, groupYMarginTop, groupYMarginBottom, groupXMargin, groupXMargin, d)
} else {
marginRectDLU(&r, 1, 1, 1, 1, d)
}
g.child.resize(int(r.left), int(r.top), int(r.right - r.left), int(r.bottom - r.top), d)
}