def execute(self):
        layers = self.iface.legendInterface().layers()
        selectedLayerIndex = self.dlg.layers.currentText()
        layer=None
        for lyr in QgsMapLayerRegistry.instance().mapLayers().values():
            if lyr.name() == selectedLayerIndex:
                layer = lyr
                qgis.utils.iface.setActiveLayer(layer)
                expr = QgsExpression(" "BORONAME" = 'The Bronx'")
                it = layer.getFeatures( QgsFeatureRequest( expr ) )
                ids = [i.id() for i in it]
                layer.setSelectedFeatures( ids )
                self.dlg.expression.setText(" ")
                self.dlg.lineEdit.setText(" ")
            break