Unigine.WidgetDialogFile Class

// widgets to be used and callback functions for them
	WidgetLabel file_name;
	WidgetButton open_button;
	WidgetDialogFile file_dialog;
	// callback to be fired on clicking the button displaying the file dialog
	void on_button_clicked()
	{
		// resetting file sepection, showing the dialog and setting permanent focus to it
		file_dialog.File = "";
		file_dialog.Hidden = false;
		file_dialog.SetPermanentFocus();
	}

	// callback to be fired on clicking the Ok button of the file dialog
	void dialog_ok_clicked()
	{
		// getting the current path selection fron the dialog and checking if the file exists
		string path = file_dialog.File;
		if(!FileSystem.IsFileExist(path))
			return;
		
		// if the file exists hiding the dialog, displaying the selected file on the "file_name" label and removing focus
		file_dialog.Hidden = true;
		file_name.Text = path;
		file_dialog.RemoveFocus();
	}

	// callback to be fired on clicking the Cancel button of the file dialog
	void dialog_cancel_clicked()
	{
		file_dialog.Hidden = true;
		file_dialog.RemoveFocus();
	}

	EventConnections connections = new EventConnections();

	void Init()
	{
		// getting a pointer to the system GUI
		Gui gui = Gui.GetCurrent();
		
		// creating a label widget to display the file selected via the dialog
		file_name = new WidgetLabel(gui, "No file selected yet");
		gui.AddChild(file_name, Gui.ALIGN_TOP | Gui.ALIGN_BACKGROUND);
		
		// creating a button widget to display the file dialog
		open_button = new WidgetButton(gui, "Select an image file on disk");
		gui.AddChild(open_button, Gui.ALIGN_TOP | Gui.ALIGN_BACKGROUND);
		
		// setting "on_button_clicked" function to handle CLICKED event for the button
		open_button.EventClicked.Connect(connections, on_button_clicked);

		// creating a file dialog widget and setting its caption, default path and file extensions filter to display only *.png and *.jpeg files
		file_dialog = new WidgetDialogFile(gui, "File open dialog");
		file_dialog.Path = "./";
		file_dialog.Filter = ".png.jpeg";

		// setting "dialog_ok_clicked" function to handle CLICKED event for dialog Ok button
		file_dialog.GetOkButton().EventClicked.Connect(connections, dialog_ok_clicked);

		// setting "dialog_cancel_clicked" function to handle CLICKED event for dialog Cancel button
		file_dialog.GetCancelButton().EventClicked.Connect(connections,dialog_cancel_clicked);

		// adding the created file dialog widget to the system GUI and hiding it
		file_dialog.Hidden = true;
		gui.AddChild(file_dialog, Gui.ALIGN_OVERLAP | Gui.ALIGN_CENTER);
		
	}