Add SelectDirectoryDialog

Fixes #67

2 files changed, 29 insertions, 1 deletions

diff --git a/src/nigui/private/windows/platform_impl.nim b/src/nigui/private/windows/platform_impl.nim
index f110722..05b0f8b 100755
--- a/src/nigui/private/windows/platform_impl.nim
+++ b/src/nigui/private/windows/platform_impl.nim
@@ -499,6 +499,7 @@ method run*(dialog: OpenFileDialog) =
 
 method run(dialog: SaveFileDialog) =
   const maxCharacters = 500
+  dialog.file = ""
   var ofn: OpenFileName
   ofn.lStructSize = OpenFileName.sizeOf.int32
   ofn.lpstrTitle = dialog.title.pUtf8ToUtf16()
@@ -517,11 +518,23 @@ method run(dialog: SaveFileDialog) =
   if ret:
     dialog.file = pUtf16ToUtf8(s, true)
   else:
-    dialog.file = ""
     let e = CommDlgExtendedError()
     if e != 0:
       raiseError("CommDlg Error Code: " & $e)
 
+method run*(dialog: SelectDirectoryDialog) =
+  ## Notes: `dialog.startDirectory` is not supported.
+  const maxCharacters = 5000
+  dialog.selectedDirectory = ""
+  var bi: BrowseInfo
+  bi.lpszTitle = dialog.title.pUtf8ToUtf16()
+  bi.ulFlags = BIF_RETURNONLYFSDIRS or BIF_NEWDIALOGSTYLE
+  let pidl = SHBrowseForFolderW(bi)
+  if pidl != nil:
+    var s = newString(maxCharacters * 2)
+    SHGetPathFromIDListW(pidl, s)
+    dialog.selectedDirectory = pUtf16ToUtf8(s, true)
+
 
 # ----------------------------------------------------------------------------------------
 #                                       Timers
diff --git a/src/nigui/private/windows/windows.nim b/src/nigui/private/windows/windows.nim
index 0cd0add..a9b275d 100755
--- a/src/nigui/private/windows/windows.nim
+++ b/src/nigui/private/windows/windows.nim
@@ -34,6 +34,8 @@ const
   ACTCTX_FLAG_ASSEMBLY_DIRECTORY_VALID* = 4
   ACTCTX_FLAG_RESOURCE_NAME_VALID* = 8
   ACTCTX_FLAG_SET_PROCESS_DEFAULT* = 16
+  BIF_RETURNONLYFSDIRS* = 0x00000001
+  BIF_NEWDIALOGSTYLE* = 0x00000040
   BN_CLICKED* = 0
   BM_SETSTYLE* = 244
   BM_SETIMAGE* = 247
@@ -348,6 +350,17 @@ type
     Scan0*: ptr UncheckedArray[byte]
     Reserved: pointer
 
+  BrowseInfo* = object
+    hwndOwner*: pointer
+    pidlRoot*: pointer
+    pszDisplayName*: cstring
+    lpszTitle*: cstring
+    ulFlags*: uint
+    lpfn*: pointer
+    lParam*: pointer
+    iImage*: int32
+
+
 
 # ----------------------------------------------------------------------------------------
 #                               Replacement for Windows Macros
@@ -529,6 +542,8 @@ proc GdipBitmapUnlockBits*(bitmap: pointer, lockedBitmapData: var BitmapData): i
 proc DragAcceptFiles*(hWnd: pointer, fAccept: bool) {.importc: "DragAcceptFiles", libShell32.}
 proc DragQueryFileW*(hDrop: pointer, iFile: uint32, lpszFile: cstring, cch: int32): int32 {.importc: "DragQueryFileW", libShell32.}
 proc DragFinish*(hDrop: pointer) {.importc: "DragFinish", libShell32.}
+proc SHBrowseForFolderW*(lpbi: var BrowseInfo): pointer {.importc: "SHBrowseForFolderW", libShell32.}
+proc SHGetPathFromIDListW*(pidl: pointer, pszPath: cstring) {.importc: "SHGetPathFromIDListW", libShell32.}
 
 
 # ----------------------------------------------------------------------------------------