Question

我试图在MainPage.cs中运行以下内容：

public class MainPage : ContentPage
{
    //...

    protected override async void OnStart()
    {
        var request = new GeolocationRequest(GeolocationAccuracy.Best);
        var location = await Geolocation.GetLocationAsync(request);
        Position position = new Position(location.Latitude, location.Longitude);
        Geocoder geocoder = new Geocoder();
        var f = await geocoder.GetAddressesForPositionAsync(position);

        Debug.WriteLine(string.Join(",", f));
        Debug.WriteLine("exeuctie");
    }
}

但是，我收到了错误MainPage.OnStart() No Suitable Method Found to Override。

在添加OnStart之前，我的应用程序运行良好。

Answer 1

ContentPage没有OnStart方法；只有Application有OnStart。

您可以在OnAppearing上使用ContentPage。每当屏幕上出现ContentPage时，就会触发以下代码：

protected override async void OnAppearing()
{
    var request = new GeolocationRequest(GeolocationAccuracy.Best);
    var location = await Geolocation.GetLocationAsync(request);
    Position position = new Position(location.Latitude, location.Longitude);
    Geocoder geocoder = new Geocoder();
    var f = await geocoder.GetAddressesForPositionAsync(position);

    Debug.WriteLine(string.Join(",", f));
    Debug.WriteLine("exeuctie");
}

MainPage.OnStart（）找不到适合的方法来重写

1 个答案: