Squashed 'libraries/ZWidget/' changes from b5ae8c8ab0..bac2a2edc5

bac2a2edc5 Exclude SDL2 from Windows compilation.
5b859bfd84 WaylandDisplayBackend: If the clicked window has a locked mouse, hide the cursor afterwards
ce76df6aa6 WaylandDisplayBackend: Add a TODO about XDG_Activation
a0ba04275b WaylandDisplayWindow: Move XDG Activation Token outside activate()

git-subtree-dir: libraries/ZWidget
git-subtree-split: bac2a2edc52cf12d1223244251876e9c4533e614

include/zwidget/systemdialogs/open_folder_dialog.h

@@ -0,0 +1,30 @@
+
+#pragma once
+
+#include <memory>
+#include <string>
+
+class Widget;
+
+/// \brief Displays the system folder browsing dialog
+class OpenFolderDialog
+{
+public:
+	/// \brief Constructs an browse folder dialog.
+	static std::unique_ptr<OpenFolderDialog> Create(Widget*owner);
+
+	virtual ~OpenFolderDialog() = default;
+
+	/// \brief Get the full path of the directory selected.
+	virtual std::string SelectedPath() const = 0;
+
+	/// \brief Sets the initial directory that is displayed.
+	virtual void SetInitialDirectory(const std::string& path) = 0;
+
+	/// \brief Sets the text that appears in the title bar.
+	virtual void SetTitle(const std::string& title) = 0;
+
+	/// \brief Shows the file dialog.
+	/// \return true if the user clicks the OK button of the dialog that is displayed, false otherwise.
+	virtual bool Show() = 0;
+};