1 files changed, 50 insertions, 0 deletions
diff --git a/prevlib/dialog_windows.go b/prevlib/dialog_windows.go
new file mode 100644
index 0000000..5095999
--- /dev/null
+++ b/prevlib/dialog_windows.go
@@ -0,0 +1,50 @@
+// 7 february 2014
+
+package ui
+
+import (
+	"fmt"
+	"os"
+)
+
+var (
+	_messageBox = user32.NewProc("MessageBoxW")
+)
+
+var dialogResponses = map[uintptr]Response{
+	_IDOK:		OK,
+}
+
+func _msgBox(parent *Window, primarytext string, secondarytext string, uType uint32) Response {
+	// http://msdn.microsoft.com/en-us/library/windows/desktop/aa511267.aspx says "Use task dialogs whenever appropriate to achieve a consistent look and layout. Task dialogs require Windows Vista® or later, so they aren't suitable for earlier versions of Windows. If you must use a message box, separate the main instruction from the supplemental instruction with two line breaks."
+	text := primarytext
+	if secondarytext != "" {
+		text += "\n\n" + secondarytext
+	}
+	ptext := toUTF16(text)
+	ptitle := toUTF16(os.Args[0])
+	parenthwnd := _HWND(_NULL)
+	if parent != dialogWindow {
+		parenthwnd = parent.sysData.hwnd
+		uType |= _MB_APPLMODAL // only for this window
+	} else {
+		uType |= _MB_TASKMODAL // make modal to every window in the program (they're all windows of the uitask, which is a single thread)
+	}
+	r1, _, err := _messageBox.Call(
+		uintptr(parenthwnd),
+		utf16ToArg(ptext),
+		utf16ToArg(ptitle),
+		uintptr(uType))
+	if r1 == 0 { // failure
+		panic(fmt.Sprintf("error displaying message box to user: %v\nstyle: 0x%08X\ntitle: %q\ntext:\n%s", err, uType, os.Args[0], text))
+	}
+	return dialogResponses[r1]
+}
+
+func (w *Window) msgBox(primarytext string, secondarytext string) {
+	_msgBox(w, primarytext, secondarytext, _MB_OK)
+}
+
+func (w *Window) msgBoxError(primarytext string, secondarytext string) {
+	_msgBox(w, primarytext, secondarytext, _MB_OK|_MB_ICONERROR)
+}