draft.16

handleDroppedFiles(selection, files) {
  const filteredFiles = files
    .filter(file => (file.type.indexOf('image/') === 0)); // <-- [1]

  if (!filteredFiles.length) {
    return 'not_handled';
  }

  this.onChange(addNewBlockAt( // <-- [2]
    this.state.editorState, 
    selection.getAnchorKey(),
    'SLIDER',
    new Map({ slides: _map(
      filteredFiles,
      file => ({ url: urlCreator.createObjectURL(file) }) // <-- [3]
    )})
  ));

  return 'handled';
}