@Override
  public boolean isAvailable(@NotNull Project project, Editor editor, PsiFile file) {
    if (!(file instanceof XmlFile)) return false;

    PsiElement element = file.findElementAt(editor.getCaretModel().getOffset());
    XmlAttributeValue value = PsiTreeUtil.getParentOfType(element, XmlAttributeValue.class);
    if (value == null) return false;
    XmlAttribute attribute = PsiTreeUtil.getParentOfType(value, XmlAttribute.class);
    if (attribute != null && attribute.isNamespaceDeclaration()) {
      setText(XmlBundle.message(getQuickFixKeyId()));
      return true;
    }
    return false;
  }
@Override
  public boolean isAvailable(@NotNull Project project, Editor editor, PsiFile file)