static JList showFilesListWithAction(S title, L<File> files, final VF1<File> action) {
  ret setPIFrameTitle(title, showFilesListWithAction(files, action));
}

static JList showFilesListWithAction(L<File> files, final VF1<File> action) {
  ret onDoubleClickOrEnter(showList(map f2s(files)), voidfunc(S path) {
    callF(action, newFile(path));
  });
}