andlabs-ui/redo/sizing.go

61 lines
1.7 KiB
Go

// 25 june 2014
package ui
type allocation struct {
x int
y int
width int
height int
this Control
neighbor Control
}
type sizingbase struct {
xmargin int
ymargin int
xpadding int
ypadding int
}
type controlSizing interface {
allocate(x int, y int, width int, height int, d *sizing) []*allocation
preferredSize(*sizing) (int, int)
commitResize(*allocation, *sizing)
getAuxResizeInfo(*sizing)
}
// on Windows, this is only embedded by window, as all other containers cannot have their own children; beginResize() points to an instance method literal (TODO get correct term) from window
// on GTK+ and Mac OS X, one is embedded by window and all containers; beginResize() points to a global function (TODO NOT GOOD; ideally the sizing data should be passed across size-allocate requests)
type container struct {
child Control
spaced bool
beginResize func() (d *sizing) // for the initial call
d *sizing // for recursive calls
}
func (c *container) resize(width, height int) {
if c.child == nil { // no children; nothing to do
return
}
if c.d == nil { // initial call
if c.beginResize == nil {
// should be a recursive call, but is not
// TODO get rid of this
return
}
c.d = c.beginResize()
defer c.endResize(c.d)
}
d := c.d
allocations := c.child.allocate(0, 0, width, height, d)
c.translateAllocationCoords(allocations, width, height)
// move in reverse so as to approximate right->left order so neighbors make sense
for i := len(allocations) - 1; i >= 0; i-- {
allocations[i].this.commitResize(allocations[i], d)
}
// always set c.d to nil so it can be garbage-collected
// the c.endResize() above won't matter since the c.d there is evaluated then, not when c.endResize() is called
c.d = nil
}