Xamarin.forms Navigation.PushModalAsync在xamarin格式的TapSirtation中给出时不工作

这里sub_header是一个标签，点击手势就是给它的。调试时，控件将转到“DisplayContent”页，但视图仍在同一页内。有人能帮忙吗？

如下更改代码

var tapGestureRecognizer1 = new TapGestureRecognizer();

sub_header.GestureRecognizers.Add(tapGestureRecognizer1);

tapGestureRecognizer1.Tapped += (s, e) =>
{
                             Navigation.PushModalAsync(new DisplayContent());
};

---

将wait与PushModalAsync一起使用

var tapGestureRecognizer1 = new TapGestureRecognizer();
tapGestureRecognizer1.Tapped += (s, e) =>
                  {
                      Navigation.PushModalAsync(new DisplayContent());
                  };

sub_header.GestureRecognizers.Add(tapGestureRecognizer1);