How to reopen folder select dialog (probbably by clearing string property) I want to create a function that:


checks if a file test.txt is in a location from filepath variable
if it is not the displays the dialog again


I've got this:

class FileBrowserOperator(bpy.types.Operator):

    bl_idname = "object.file_browser_operator"
    bl_label = "File browser Operator"

    filepath = bpy.props.StringProperty(subtype="DIR_PATH")

    def execute(self, context):
        while not os.path.isfile(
                        context.scene.content_path + '/test.txt'): 

            context.scene.content_path = self.filepath
            print("Path:")
            print(context.scene.content_path)
        return {'FINISHED'}  
    [...]


But it shows the dialog only once. I assume, that at the beginning of the loop I've got to clear this value somehow, but I do not know how.
Thank You in advence
I'd suggest just recall the operator, eg  the operator file export template operator_file_export.py  Used a directory property for a folder path, to keep filepath as a file path (usual usage).

class ExportSomeData(Operator, ExportHelper):
    """This appears in the tooltip of the operator and in the generated docs"""
    bl_idname = "export_test.some_data"  # important since its how bpy.ops.import_test.some_data is constructed
    bl_label = "Export Some Data"

    # ExportHelper mixin class uses this
    filename_ext = ".txt"

    filter_glob = StringProperty(
            default="*.txt",
            options={'HIDDEN'},
            maxlen=255,  # Max internal buffer length, longer would be clamped.
            )

    directory = StringProperty(subtype='DIR_PATH')

    def execute(self, context):
        if os.path.isfile(os.path.join(self.directory, "test.txt")):
            return {'FINISHED'}
        else:
            return bpy.ops.export_test.some_data('INVOKE_DEFAULT')