Source code for camelot.view.action_steps.select_file

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from PyQt4 import QtGui, QtCore
  
from camelot.admin.action import ActionStep
from camelot.view.action_runner import hide_progress_dialog
from camelot.core.exception import CancelRequest

class SelectFile( ActionStep ):
    """Select one or more files to open or to process.
    
    :param file_name_filter: Filter on the names of the files that can
        be selected, such as 'All files (*)'.  
        See :class:`QtGui.QFileDialog` for more documentation.
    
    .. attribute:: single
    
        defaults to :const:`True`, set to :const:`False` if selection
        of multiple files is allowed

    .. attribute:: existing
    
        defaults to :const:`True`, set to :const:`False` if non existing
        files are allowed (to save something)
        
    The :keyword:`yield` statement of :class:`SelectFile` returns a list
    of selected file names.  This list has only one element when single is
    set to :const:`True`.  Raises a 
    :class:`camelot.core.exception.CancelRequest` when no file was selected.
    
    .. image:: /_static/actionsteps/select_file.png
    
    This action step stores its last location into the :class:`QtCore.QSettings` 
    and uses it as the initial location the next time it is invoked.
    """
    
    def __init__( self, file_name_filter = '' ):
        self.file_name_filter = file_name_filter
        self.single = True
        self.existing = True
    
    def render( self, directory = None ):
        """create the file dialog widget. this method is used to unit test
        the action step.

        :param directory: the directory in which to open the dialog, None to
            use the default
        """
        dialog = QtGui.QFileDialog( filter = self.file_name_filter,
                                    directory = (None or '') )
        if self.existing == False:
            file_mode = QtGui.QFileDialog.AnyFile
        else:
            if self.single == True:
                file_mode = QtGui.QFileDialog.ExistingFile
            else:
                file_mode = QtGui.QFileDialog.ExistingFiles
        dialog.setFileMode( file_mode )
        return dialog
    
    def gui_run( self, gui_context ):
        settings = QtCore.QSettings()
        directory = settings.value( 'datasource' ).toString()
        dialog = self.render( directory )
        with hide_progress_dialog( gui_context ):
            if dialog.exec_() == QtGui.QDialog.Rejected:
                raise CancelRequest()
            file_names = [unicode(fn) for fn in dialog.selectedFiles()]
            if file_names:
                settings.setValue( 'datasource', QtCore.QVariant( file_names[0] ) )
            return file_names