1 files changed, 52 insertions, 0 deletions
diff --git a/container.go b/container.go
new file mode 100644
index 0000000..c855072
--- /dev/null
+++ b/container.go
@@ -0,0 +1,52 @@
+// 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
+	ymargintop		int
+	ymarginbottom	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)
+}
+
+// A container hosts a Control and resizes that Control based on changes in size to the parent Window.
+// container is used by Window, Tab, and Group to contain and control their respective Controls.
+// Tab and Group use containers for their content; as such, their commitResize() functions should only change the size of the Tab and Group themselves, and have their containers do the real work.
+// All containers must embed containerbase.
+type containerbase struct {
+	child		Control
+}
+
+// set to true to apply spacing to all windows
+var spaced bool = false
+
+func (c *container) resize(x, y, width, height int) {
+	if c.child == nil {		// no children; nothing to do
+		return
+	}
+	d := c.beginResize()
+	allocations := c.child.allocate(x + d.xmargin, y + d.ymargintop,
+		width - (2 * d.xmargin), height - d.ymargintop - d.ymarginbottom, 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)
+	}
+}