...in with the new.

1 files changed, 147 insertions, 0 deletions

diff --git a/container_windows.go b/container_windows.go
new file mode 100644
index 0000000..d3fd327
--- /dev/null
+++ b/container_windows.go
@@ -0,0 +1,147 @@
+// 4 august 2014
+
+package ui
+
+import (
+	"fmt"
+	"syscall"
+	"unsafe"
+)
+
+// #include "winapi_windows.h"
+import "C"
+
+type container struct {
+	containerbase
+	hwnd		C.HWND
+	nchildren		int
+	isGroup		bool
+}
+
+type sizing struct {
+	sizingbase
+
+	// for size calculations
+	baseX			C.int
+	baseY			C.int
+	internalLeading	C.LONG		// for Label; see Label.commitResize() for details
+
+	// for the actual resizing
+	// possibly the HDWP
+}
+
+func makeContainerWindowClass() error {
+	var errmsg *C.char
+
+	err := C.makeContainerWindowClass(&errmsg)
+	if err != 0 || errmsg != nil {
+		return fmt.Errorf("%s: %v", C.GoString(errmsg), syscall.Errno(err))
+	}
+	return nil
+}
+
+func newContainer(control Control) *container {
+	c := new(container)
+	hwnd := C.newContainer(unsafe.Pointer(c))
+	if hwnd != c.hwnd {
+		panic(fmt.Errorf("inconsistency: hwnd returned by CreateWindowEx() (%p) and hwnd stored in container (%p) differ", hwnd, c.hwnd))
+	}
+	c.child = control
+	c.child.setParent(&controlParent{c})
+	return c
+}
+
+func (c *container) setParent(hwnd C.HWND) {
+	C.controlSetParent(c.hwnd, hwnd)
+}
+
+// this is needed because Windows won't move/resize a child window for us
+func (c *container) move(r *C.RECT) {
+	C.moveWindow(c.hwnd, C.int(r.left), C.int(r.top), C.int(r.right - r.left), C.int(r.bottom - r.top))
+}
+
+func (c *container) show() {
+	C.ShowWindow(c.hwnd, C.SW_SHOW)
+}
+
+func (c *container) hide() {
+	C.ShowWindow(c.hwnd, C.SW_HIDE)
+}
+
+//export storeContainerHWND
+func storeContainerHWND(data unsafe.Pointer, hwnd C.HWND) {
+	c := (*container)(data)
+	c.hwnd = hwnd
+}
+
+//export containerResize
+func containerResize(data unsafe.Pointer, r *C.RECT) {
+	c := (*container)(data)
+	// the origin of any window's content area is always (0, 0), but let's use the values from the RECT just to be safe
+	c.resize(int(r.left), int(r.top), int(r.right - r.left), int(r.bottom - r.top))
+}
+
+// For Windows, Microsoft just hands you a list of preferred control sizes as part of the MSDN documentation and tells you to roll with it.
+// These sizes are given in "dialog units", which are independent of the font in use.
+// We need to convert these into standard pixels, which requires we get the device context of the OS window.
+// References:
+// - http://msdn.microsoft.com/en-us/library/ms645502%28VS.85%29.aspx - the calculation needed
+// - http://support.microsoft.com/kb/125681 - to get the base X and Y
+// (thanks to http://stackoverflow.com/questions/58620/default-button-size)
+// In my tests (see https://github.com/andlabs/windlgunits), the GetTextExtentPoint32() option for getting the base X produces much more accurate results than the tmAveCharWidth option when tested against the sample values given in http://msdn.microsoft.com/en-us/library/windows/desktop/dn742486.aspx#sizingandspacing, but can be off by a pixel in either direction (probably due to rounding errors).
+
+// note on MulDiv():
+// div will not be 0 in the usages below
+// we also ignore overflow; that isn't likely to happen for our use case anytime soon
+
+func fromdlgunitsX(du int, d *sizing) int {
+	return int(C.MulDiv(C.int(du), d.baseX, 4))
+}
+
+func fromdlgunitsY(du int, d *sizing) int {
+	return int(C.MulDiv(C.int(du), d.baseY, 8))
+}
+
+const (
+	marginDialogUnits = 7
+	paddingDialogUnits = 4
+
+	groupXMargin = 6
+	groupYMarginTop = 11		// note this value /includes the groupbox label/
+	groupYMarginBottom = 7
+)
+
+func (c *container) beginResize() (d *sizing) {
+	var baseX, baseY C.int
+	var internalLeading C.LONG
+
+	d = new(sizing)
+
+	C.calculateBaseUnits(c.hwnd, &baseX, &baseY, &internalLeading)
+	d.baseX = baseX
+	d.baseY = baseY
+	d.internalLeading = internalLeading
+
+	if spaced {
+		d.xmargin = fromdlgunitsX(marginDialogUnits, d)
+		d.ymargintop = fromdlgunitsY(marginDialogUnits, d)
+		d.ymarginbottom = d.ymargintop
+		d.xpadding = fromdlgunitsX(paddingDialogUnits, d)
+		d.ypadding = fromdlgunitsY(paddingDialogUnits, d)
+	}
+	if c.isGroup {
+		// note that these values apply regardless of whether or not spaced is set
+		// this is because Windows groupboxes have the client rect spanning the entire size of the control, not just the active work area
+		// the measurements Microsoft give us are for spaced margining; let's just use them
+		d.xmargin = fromdlgunitsX(groupXMargin, d)
+		d.ymargintop = fromdlgunitsY(groupYMarginTop, d)
+		d.ymarginbottom = fromdlgunitsY(groupYMarginBottom, d)
+
+	}
+
+	return d
+}
+
+func (c *container) translateAllocationCoords(allocations []*allocation, winwidth, winheight int) {
+	// no translation needed on windows
+}