xadmin列表页添加自定义工具栏toolbar

通过xadmin的Plugin实现，adminx.py中

class Link2AdminPlugin(BaseAdminPlugin):
    link_2_admin = False

    def init_request(self, *args, **kwargs):
        return bool(self.link_2_admin)

    #my_top_toolbar为xadmin model_list.html中存在的view_block区块
    def block_my_top_toolbar(self, context, nodes):
       nodes.append(loader.render_to_string('product/blocks/my_top_toolbar.link_2_admin.html', context_instance=context))

xadmin.site.register_plugin(Link2AdminPlugin, ListAdminView)class Li