First you need to create a filter to your views. Add "Feeds log: Importer id" filter to All entries display / tab. Then this code snippet alters the form so there won't be textfield, but selection.
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function HOOK_form_alter(&$form, &$form_state, $form_id) { // replace HOOK with your module name // filter feeds log by Importer if ($form_id == 'views_exposed_form') { $result = db_query('SELECT * FROM {feeds_importer}'); if ($result -> rowCount() > 0) foreach ($result as $row) { $options[$importer['name']] = $importer['name']; } } }Programming Language: PHP