From 7e0a8968c1612a3dd81477a90fba738431cdc65f Mon Sep 17 00:00:00 2001
From: Pietro Gagliardi <pietro10@mac.com>
Date: Wed, 15 Oct 2014 11:17:34 -0400
Subject: [PATCH] Migrated Tab.

---
 newctrl/tab_windows.go | 115 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 newctrl/tab_windows.go

diff --git a/newctrl/tab_windows.go b/newctrl/tab_windows.go
new file mode 100644
index 0000000..f4481c6
--- /dev/null
+++ b/newctrl/tab_windows.go
@@ -0,0 +1,115 @@
+// 25 july 2014
+
+package ui
+
+import (
+	"unsafe"
+)
+
+// #include "winapi_windows.h"
+import "C"
+
+/*
+On Windows, container controls are just regular controls that notify their parent when the user wants to do things; changing the contents of a switching container (such as a tab control) must be done manually.
+
+We'll create a dummy window using the container window class for each tab page. This makes showing and hiding tabs a matter of showing and hiding one control.
+*/
+
+type tab struct {
+	*controlSingleHWND
+	tabs		[]*container
+	children	[]Control
+}
+
+func newTab() Tab {
+	hwnd := C.newControl(C.xWC_TABCONTROL,
+		C.TCS_TOOLTIPS|C.WS_TABSTOP,
+		0) // don't set WS_EX_CONTROLPARENT here; see uitask_windows.c
+	t := &tab{
+		controlSingleHWND:		newControlSingleHWND(hwnd),
+	}
+	t.fpreferredSize = t.preferredSize
+	t.fresize = t.resize
+	C.controlSetControlFont(t.hwnd)
+	C.setTabSubclass(t.hwnd, unsafe.Pointer(t))
+	return t
+}
+
+// TODO margined
+func (t *tab) Append(name string, control Control) {
+	c := newContainer()
+	control.setParent(&containerParent{c.hwnd})
+	t.tabs = append(t.tabs, c)
+	t.children = append(t.children, control)
+	// initially hide tab 1..n controls; if we don't, they'll appear over other tabs, resulting in weird behavior
+	if len(t.tabs) != 1 {
+		t.tabs[len(t.tabs)-1].hide()
+	}
+	C.tabAppend(t.hwnd, toUTF16(name))
+}
+
+//export tabChanging
+func tabChanging(data unsafe.Pointer, current C.LRESULT) {
+	t := (*tab)(data)
+	t.tabs[int(current)].hide()
+}
+
+//export tabChanged
+func tabChanged(data unsafe.Pointer, new C.LRESULT) {
+	t := (*tab)(data)
+	t.tabs[int(new)].show()
+}
+
+//export tabTabHasChildren
+func tabTabHasChildren(data unsafe.Pointer, which C.LRESULT) C.BOOL {
+	t := (*tab)(data)
+	if len(t.tabs) == 0 { // currently no tabs
+		return C.FALSE
+	}
+return C.TRUE/*TODO
+	if t.tabs[int(which)].nchildren > 0 {
+		return C.TRUE
+	}
+	return C.FALSE
+*/
+}
+
+func (t *tab) preferredSize(d *sizing) (width, height int) {
+	for _, s := range t.tabs {
+		w, h := s.child.preferredSize(d)
+		if width < w {
+			width = w
+		}
+		if height < h {
+			height = h
+		}
+	}
+	return width, height + int(C.tabGetTabHeight(t.hwnd))
+}
+
+// a tab control contains other controls; size appropriately
+func (t *tab) resize(x int, y int, width int, height int, d *sizing) {
+	// first, chain up to the container base to keep the Z-order correct
+	// TODO use a variable for this
+	t.controlSingleHWND.resize(x, y, width, height, d)
+
+	// now resize the children
+	var r C.RECT
+
+	// figure out what the rect for each child is...
+	// the tab contents are children of the tab itself, so ignore x and y, which are relative to the window!
+	r.left = C.LONG(0)
+	r.top = C.LONG(0)
+	r.right = C.LONG(width)
+	r.bottom = C.LONG(height)
+	C.tabGetContentRect(t._hwnd, &r)
+	// and resize tabs
+	// don't resize just the current tab; resize all tabs!
+	for i, _ := range t.tabs {
+		// because each widget is actually a child of the Window, the origin is the one we calculated above
+		t.tabs[i].resize(int(r.left), int(r.top), int(r.right - r.left), int(r.bottom - r.top), d)
+		t.children[i].resize(int(r.left), int(r.top), int(r.right - r.left), int(r.bottom - r.top), d)
+	}
+	// and now resize the tab control itself
+	basecommitResize(t, c, d)
+}