C# Xamarin活动指示灯不工作
我在获取要在Xamarin.Forms应用程序中显示的活动指示器时遇到问题。我正在使用XAML和代码隐藏，它绑定到一个视图模型 在我看来，所有的设置都是正确的，当我逐步阅读代码时，我可以看到IsBusy属性被适当地设置为True和False，但实际的ActivityIndicator根本不显示 有人能看出我做错了什么吗 Login.Xaml.CsC# Xamarin活动指示灯不工作,c#,xaml,xamarin,xamarin.forms,C#,Xaml,Xamarin,Xamarin.forms,我在获取要在Xamarin.Forms应用程序中显示的活动指示器时遇到问题。我正在使用XAML和代码隐藏，它绑定到一个视图模型 在我看来，所有的设置都是正确的，当我逐步阅读代码时，我可以看到IsBusy属性被适当地设置为True和False，但实际的ActivityIndicator根本不显示 有人能看出我做错了什么吗 Login.Xaml.Cs using RestSharp; using System; using System.Collections.Generic; using Syst
using RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.Views
{
public partial class Login : ContentPage
{
public Login ()
{
InitializeComponent ();
var viewModel = new LoginViewModel();
BindingContext = viewModel;
ToolbarItems.Add(new ToolbarItem("New", "addperson.png", async () =>
{
await Navigation.PushAsync(new Register());
}));
}
public string CleanResponse(string reason)
{
var str = reason;
var charsToRemove = new string[] { "[", "]", "{", "}", "\"" };
foreach (var c in charsToRemove)
{
str = str.Replace(c, string.Empty);
}
return str;
}
async void OnLogin(object sender, EventArgs e)
{
//Validations here
if (email.Text == "")
{
await DisplayAlert("Validation Error", "You must enter an Email address", "OK");
return;
}
else if (password.Text == "")
{
await DisplayAlert("Validation Error", "You must enter a Password", "OK");
return;
}
//We are good to go
else
{
this.IsBusy = true;
string APIServer = Application.Current.Properties["APIServer"].ToString();
var client = new RestClient(APIServer);
var request = new RestRequest("api/account/sign-in", Method.POST);
request.AddHeader("Content-type", "application/json");
request.AddJsonBody(new
{
email = email.Text,
password = password.Text
}
);
var response = client.Execute(request) as RestResponse;
this.IsBusy = false;
//Valid response
if (response.StatusCode.ToString() == "OK")
{
var tokenobject = JsonConvert.DeserializeObject<TokenModel>(response.Content);
Application.Current.Properties["Token"] = tokenobject.Access_token;
string token = Application.Current.Properties["Token"].ToString();
App.Current.MainPage = new NavigationPage(new MainPage());
}
//Error response
else
{
var statuscode = response.StatusCode.ToString();
var content = response.Content;
var exception = response.ErrorException;
var error = response.ErrorMessage;
var statusdesc = response.StatusDescription;
await DisplayAlert("Login Failed", "Your login has failed. Please check your details and try again.", "OK");
}
}
}
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
namespace TechsportiseApp.ViewModels
{
public class LoginViewModel : INotifyPropertyChanged
{
private bool _isBusy;
public bool IsBusy
{
get { return _isBusy; }
set
{
if (_isBusy == value)
return;
_isBusy = value;
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
var changed = PropertyChanged;
if (changed != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}
您没有通知
IsBusyusing RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.Views
{
public partial class Login : ContentPage
{
public Login ()
{
InitializeComponent ();
var viewModel = new LoginViewModel();
BindingContext = viewModel;
ToolbarItems.Add(new ToolbarItem("New", "addperson.png", async () =>
{
await Navigation.PushAsync(new Register());
}));
}
public string CleanResponse(string reason)
{
var str = reason;
var charsToRemove = new string[] { "[", "]", "{", "}", "\"" };
foreach (var c in charsToRemove)
{
str = str.Replace(c, string.Empty);
}
return str;
}
}
}
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="TechsportiseApp.Views.Login">
<ContentPage.Padding>
<OnPlatform x:TypeArguments="Thickness"
iOS="20, 40, 20, 20"
Android="20, 20, 20, 20"
WinPhone="20, 20, 20, 20" />
</ContentPage.Padding>
<ContentPage.Content>
<AbsoluteLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<StackLayout VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
Orientation="Vertical"
AbsoluteLayout.LayoutFlags="All" AbsoluteLayout.LayoutBounds="0,0,1,1">
<ScrollView Orientation = "Vertical" VerticalOptions="StartAndExpand">
<StackLayout VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
Orientation="Vertical">
<Image Source = "splash.png" HorizontalOptions="Center" />
<Label Text="Race Director"
FontAttributes="Bold"
FontSize="Large"
HorizontalTextAlignment="Center"
HorizontalOptions="CenterAndExpand" />
<Label Text="by Techsportise"
HorizontalTextAlignment="Center"
HorizontalOptions="CenterAndExpand" />
<BoxView HeightRequest="20" HorizontalOptions="FillAndExpand" />
<Entry x:Name="email" Text="{Binding Email}" Placeholder="Email address"/>
<Entry x:Name="password" Text="{Binding Password}" IsPassword="true" Placeholder="Password"/>
<Button x:Name="loginButton" Text="Login" Command="{Binding OnLoginCommand}" Style="{StaticResource Buttons}"/>
</StackLayout>
</ScrollView>
</StackLayout>
<StackLayout IsVisible="{Binding IsBusy}"
Padding="12"
AbsoluteLayout.LayoutFlags="PositionProportional"
AbsoluteLayout.LayoutBounds="0.5,0.5,1,1">
<ActivityIndicator IsRunning="{Binding IsBusy}" Color ="#80000000"/>
<Label Text="Loading..." HorizontalOptions="Center" TextColor="White"/>
</StackLayout>
</AbsoluteLayout>
</ContentPage.Content>
</ContentPage>
using System.ComponentModel;
using RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.ViewModels
{
public class LoginViewModel : INotifyPropertyChanged
{
public LoginViewModel()
{
OnLoginCommand = new Command(ExecuteOnLogin);
}
private bool _isBusy;
public bool IsBusy
{
get { return _isBusy; }
set
{
if (_isBusy == value)
return;
_isBusy = value;
OnPropertyChanged("IsBusy");
}
}
private string _email;
public string Email
{
get { return _email; }
set
{
if (_email == value)
return;
_email = value;
OnPropertyChanged("Email");
}
}
private bool _password;
public bool Password
{
get { return _password; }
set
{
if (_password == value)
return;
_password = value;
OnPropertyChanged("Password");
}
}
private async void ExecuteOnLogin()
{
//Validations here
if (Email == "")
{
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Validation Error", "You must enter an Email address", "OK"));
return;
}
else if (Password == "")
{
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Validation Error", "You must enter a Password", "OK"));
return;
}
//We are good to go
else
{
Device.BeginInvokeOnMainThread(() => IsBusy = true);
string APIServer = Application.Current.Properties["APIServer"].ToString();
var client = new RestClient(APIServer);
var request = new RestRequest("api/account/sign-in", Method.POST);
request.AddHeader("Content-type", "application/json");
request.AddJsonBody(new
{
email = Email,
password = Password
}
);
var response = client.Execute(request) as RestResponse;
Device.BeginInvokeOnMainThread(() => IsBusy = false);
//Valid response
if (response.StatusCode.ToString() == "OK")
{
var tokenobject = JsonConvert.DeserializeObject<TokenModel>(response.Content);
Application.Current.Properties["Token"] = tokenobject.Access_token;
string token = Application.Current.Properties["Token"].ToString();
App.Current.MainPage = new NavigationPage(new MainPage());
}
//Error response
else
{
var statuscode = response.StatusCode.ToString();
var content = response.Content;
var exception = response.ErrorException;
var error = response.ErrorMessage;
var statusdesc = response.StatusDescription;
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Login Failed", "Your login has failed. Please check your details and try again.", "OK"));
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
var changed = PropertyChanged;
if (changed != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public Command OnLoginCommand {get;}
}
}
using RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.Views
{
public partial class Login : ContentPage
{
public Login ()
{
InitializeComponent ();
var viewModel = new LoginViewModel();
BindingContext = viewModel;
ToolbarItems.Add(new ToolbarItem("New", "addperson.png", async () =>
{
await Navigation.PushAsync(new Register());
}));
}
public string CleanResponse(string reason)
{
var str = reason;
var charsToRemove = new string[] { "[", "]", "{", "}", "\"" };
foreach (var c in charsToRemove)
{
str = str.Replace(c, string.Empty);
}
return str;
}
}
}
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="TechsportiseApp.Views.Login">
<ContentPage.Padding>
<OnPlatform x:TypeArguments="Thickness"
iOS="20, 40, 20, 20"
Android="20, 20, 20, 20"
WinPhone="20, 20, 20, 20" />
</ContentPage.Padding>
<ContentPage.Content>
<AbsoluteLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<StackLayout VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
Orientation="Vertical"
AbsoluteLayout.LayoutFlags="All" AbsoluteLayout.LayoutBounds="0,0,1,1">
<ScrollView Orientation = "Vertical" VerticalOptions="StartAndExpand">
<StackLayout VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
Orientation="Vertical">
<Image Source = "splash.png" HorizontalOptions="Center" />
<Label Text="Race Director"
FontAttributes="Bold"
FontSize="Large"
HorizontalTextAlignment="Center"
HorizontalOptions="CenterAndExpand" />
<Label Text="by Techsportise"
HorizontalTextAlignment="Center"
HorizontalOptions="CenterAndExpand" />
<BoxView HeightRequest="20" HorizontalOptions="FillAndExpand" />
<Entry x:Name="email" Text="{Binding Email}" Placeholder="Email address"/>
<Entry x:Name="password" Text="{Binding Password}" IsPassword="true" Placeholder="Password"/>
<Button x:Name="loginButton" Text="Login" Command="{Binding OnLoginCommand}" Style="{StaticResource Buttons}"/>
</StackLayout>
</ScrollView>
</StackLayout>
<StackLayout IsVisible="{Binding IsBusy}"
Padding="12"
AbsoluteLayout.LayoutFlags="PositionProportional"
AbsoluteLayout.LayoutBounds="0.5,0.5,1,1">
<ActivityIndicator IsRunning="{Binding IsBusy}" Color ="#80000000"/>
<Label Text="Loading..." HorizontalOptions="Center" TextColor="White"/>
</StackLayout>
</AbsoluteLayout>
</ContentPage.Content>
</ContentPage>
using System.ComponentModel;
using RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.ViewModels
{
public class LoginViewModel : INotifyPropertyChanged
{
public LoginViewModel()
{
OnLoginCommand = new Command(ExecuteOnLogin);
}
private bool _isBusy;
public bool IsBusy
{
get { return _isBusy; }
set
{
if (_isBusy == value)
return;
_isBusy = value;
OnPropertyChanged("IsBusy");
}
}
private string _email;
public string Email
{
get { return _email; }
set
{
if (_email == value)
return;
_email = value;
OnPropertyChanged("Email");
}
}
private bool _password;
public bool Password
{
get { return _password; }
set
{
if (_password == value)
return;
_password = value;
OnPropertyChanged("Password");
}
}
private async void ExecuteOnLogin()
{
//Validations here
if (Email == "")
{
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Validation Error", "You must enter an Email address", "OK"));
return;
}
else if (Password == "")
{
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Validation Error", "You must enter a Password", "OK"));
return;
}
//We are good to go
else
{
Device.BeginInvokeOnMainThread(() => IsBusy = true);
string APIServer = Application.Current.Properties["APIServer"].ToString();
var client = new RestClient(APIServer);
var request = new RestRequest("api/account/sign-in", Method.POST);
request.AddHeader("Content-type", "application/json");
request.AddJsonBody(new
{
email = Email,
password = Password
}
);
var response = client.Execute(request) as RestResponse;
Device.BeginInvokeOnMainThread(() => IsBusy = false);
//Valid response
if (response.StatusCode.ToString() == "OK")
{
var tokenobject = JsonConvert.DeserializeObject<TokenModel>(response.Content);
Application.Current.Properties["Token"] = tokenobject.Access_token;
string token = Application.Current.Properties["Token"].ToString();
App.Current.MainPage = new NavigationPage(new MainPage());
}
//Error response
else
{
var statuscode = response.StatusCode.ToString();
var content = response.Content;
var exception = response.ErrorException;
var error = response.ErrorMessage;
var statusdesc = response.StatusDescription;
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Login Failed", "Your login has failed. Please check your details and try again.", "OK"));
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
var changed = PropertyChanged;
if (changed != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public Command OnLoginCommand {get;}
}
}
using RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.Views
{
public partial class Login : ContentPage
{
public Login ()
{
InitializeComponent ();
var viewModel = new LoginViewModel();
BindingContext = viewModel;
ToolbarItems.Add(new ToolbarItem("New", "addperson.png", async () =>
{
await Navigation.PushAsync(new Register());
}));
}
public string CleanResponse(string reason)
{
var str = reason;
var charsToRemove = new string[] { "[", "]", "{", "}", "\"" };
foreach (var c in charsToRemove)
{
str = str.Replace(c, string.Empty);
}
return str;
}
}
}
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="TechsportiseApp.Views.Login">
<ContentPage.Padding>
<OnPlatform x:TypeArguments="Thickness"
iOS="20, 40, 20, 20"
Android="20, 20, 20, 20"
WinPhone="20, 20, 20, 20" />
</ContentPage.Padding>
<ContentPage.Content>
<AbsoluteLayout HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand">
<StackLayout VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
Orientation="Vertical"
AbsoluteLayout.LayoutFlags="All" AbsoluteLayout.LayoutBounds="0,0,1,1">
<ScrollView Orientation = "Vertical" VerticalOptions="StartAndExpand">
<StackLayout VerticalOptions="FillAndExpand"
HorizontalOptions="FillAndExpand"
Orientation="Vertical">
<Image Source = "splash.png" HorizontalOptions="Center" />
<Label Text="Race Director"
FontAttributes="Bold"
FontSize="Large"
HorizontalTextAlignment="Center"
HorizontalOptions="CenterAndExpand" />
<Label Text="by Techsportise"
HorizontalTextAlignment="Center"
HorizontalOptions="CenterAndExpand" />
<BoxView HeightRequest="20" HorizontalOptions="FillAndExpand" />
<Entry x:Name="email" Text="{Binding Email}" Placeholder="Email address"/>
<Entry x:Name="password" Text="{Binding Password}" IsPassword="true" Placeholder="Password"/>
<Button x:Name="loginButton" Text="Login" Command="{Binding OnLoginCommand}" Style="{StaticResource Buttons}"/>
</StackLayout>
</ScrollView>
</StackLayout>
<StackLayout IsVisible="{Binding IsBusy}"
Padding="12"
AbsoluteLayout.LayoutFlags="PositionProportional"
AbsoluteLayout.LayoutBounds="0.5,0.5,1,1">
<ActivityIndicator IsRunning="{Binding IsBusy}" Color ="#80000000"/>
<Label Text="Loading..." HorizontalOptions="Center" TextColor="White"/>
</StackLayout>
</AbsoluteLayout>
</ContentPage.Content>
</ContentPage>
using System.ComponentModel;
using RestSharp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechsportiseApp.Views;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using TechsportiseApp.API;
using TechsportiseApp.ViewModels;
using TechsportiseApp.Models;
using Newtonsoft.Json;
namespace TechsportiseApp.ViewModels
{
public class LoginViewModel : INotifyPropertyChanged
{
public LoginViewModel()
{
OnLoginCommand = new Command(ExecuteOnLogin);
}
private bool _isBusy;
public bool IsBusy
{
get { return _isBusy; }
set
{
if (_isBusy == value)
return;
_isBusy = value;
OnPropertyChanged("IsBusy");
}
}
private string _email;
public string Email
{
get { return _email; }
set
{
if (_email == value)
return;
_email = value;
OnPropertyChanged("Email");
}
}
private bool _password;
public bool Password
{
get { return _password; }
set
{
if (_password == value)
return;
_password = value;
OnPropertyChanged("Password");
}
}
private async void ExecuteOnLogin()
{
//Validations here
if (Email == "")
{
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Validation Error", "You must enter an Email address", "OK"));
return;
}
else if (Password == "")
{
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Validation Error", "You must enter a Password", "OK"));
return;
}
//We are good to go
else
{
Device.BeginInvokeOnMainThread(() => IsBusy = true);
string APIServer = Application.Current.Properties["APIServer"].ToString();
var client = new RestClient(APIServer);
var request = new RestRequest("api/account/sign-in", Method.POST);
request.AddHeader("Content-type", "application/json");
request.AddJsonBody(new
{
email = Email,
password = Password
}
);
var response = client.Execute(request) as RestResponse;
Device.BeginInvokeOnMainThread(() => IsBusy = false);
//Valid response
if (response.StatusCode.ToString() == "OK")
{
var tokenobject = JsonConvert.DeserializeObject<TokenModel>(response.Content);
Application.Current.Properties["Token"] = tokenobject.Access_token;
string token = Application.Current.Properties["Token"].ToString();
App.Current.MainPage = new NavigationPage(new MainPage());
}
//Error response
else
{
var statuscode = response.StatusCode.ToString();
var content = response.Content;
var exception = response.ErrorException;
var error = response.ErrorMessage;
var statusdesc = response.StatusDescription;
Device.BeginInvokeOnMainThread(() => App.Current.MainPage.DisplayAlert("Login Failed", "Your login has failed. Please check your details and try again.", "OK"));
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName)
{
var changed = PropertyChanged;
if (changed != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
public Command OnLoginCommand {get;}
}
}
使用System.ComponentModel；
使用RestSharp；
使用制度；
使用System.Collections.Generic；
使用System.Linq；
使用系统文本；
使用System.Threading.Tasks；
使用TechsportiseApp.Views；
使用Xamarin.Forms；
使用Xamarin.Forms.Xaml；
使用TechsportiseApp.API；
使用TechsportiseApp.ViewModels；
使用TechsportiseApp.Models；
使用Newtonsoft.Json；
命名空间TechsportiseApp.ViewModels
{
公共类LoginView模型：INotifyPropertyChanged
{
公共登录视图模型（）
{
OnLoginCommand=新命令（ExecuteOnLogin）；
}
私人厕所很忙；
公共图书馆很忙
{
获取{return\u isBusy；}
设置
{
如果（_isBusy==值）
返回；
_isBusy=值；
OnPropertyChanged（“IsBusy”）；
}
}
私人字符串\u电子邮件；
公共字符串电子邮件
{
获取{return\u email；}
设置
{
如果（_email==值）
返回；
_电子邮件=价值；
OnPropertyChanged（“电子邮件”）；
}
}
私人密码；
公共bool密码
{
获取{return\u password；}
设置
{
如果（_password==值）
返回；
_密码=值；
OnPropertyChanged（“密码”）；
}
}
私有异步void ExecuteOnLogin（）
{
//这里的验证
如果（电子邮件==“”）
{
Device.beginInvokeMainThread（（）=>App.Current.MainPage.DisplayAlert（“验证错误”，“您必须输入电子邮件地址”，“确定”））；
返回；
}
else if（密码==“”）
{
Device.beginInvokeMainThread（（）=>App.Current.MainPage.DisplayAlert（“验证错误”，“必须输入密码”，“确定”））；
返回；
}
//我们可以走了
其他的
{
Device.beginInvokeMainThread（（）=>IsBusy=true）；
字符串APIServer=Application.Current.Properties[“APIServer”].ToString（）；
var client=新的RestClient（APIServer）；
var请求=新的重新请求（“api/帐户/登录”，Method.POST）；
AddHeader（“内容类型”、“应用程序/json”）；
request.AddJsonBody（新的
{
电子邮件=电子邮件，
密码=密码
}
);
var response=client.Execute（request）as response；
Device.beginInvokeMainThread（（）=>IsBusy=false）；
//有效响应
if（response.StatusCode.ToString（）=“OK”）
{
var tokenobject=JsonConvert.DeserializeObject（response.Content）；
Application.Current.Properties[“Token”]=tokenobject.Access\u Token；
字符串标记=Application.Current.Properties[“token”].ToString（）；
App.Current.MainPage=新导航页面（新主页（））；
}
//错误响应
其他的
{
var statuscode=response.statuscode.ToString（）；
var content=response.content；
var exception=response.ErrorException；
var error=response.ErrorMessage；
var statusdesc=response.StatusDescription；
Device.beginInvokeMainThread（（）=>App.Current.MainPage.DisplayAlert（“登录失败”，“您的登录失败。请检查您的详细信息，然后重试。”，“确定”））；
}
}
}
公共事件属性更改事件处理程序属性更改；
受保护的虚拟void OnPropertyChanged（字符串propertyName）
{
var changed=Property changed；
如果（已更改！=null）
{
PropertyChanged（这是新的PropertyChangedEventArgs（propertyName））；
}
}
公共命令OnLoginCommand{get；}
}
}
也许你应该把责任分开。创建一个名为
ViewModelBaseINotifyPropertyChangedpublic class LoginViewModel : ViewModelBase
{
public ICommand LoginCommand { get; set; }
#region Properties
private string _email;
public string Email
{
get { return _email; }
set { SetProperty(ref _email, value); }
}
private string _password;
public string Password
{
get { return _password; }
set { SetProperty(ref _password, value); }
}
#endregion
public LoginViewModel()
{
LoginCommand = new Command(Login);
}
public string CleanResponse(string reason)
{
var str = reason;
var charsToRemove = new string[] { "[", "]", "{", "}", "\"" };
foreach (var c in charsToRemove)
{
str = str.Replace(c, string.Empty);
}
return str;
}
private async void Login()
{
//Validations here
if (Email == "")
{
await DisplayAlert("Validation Error", "You must enter an Email address", "OK");
return;
}
else if (Password == "")
{
await DisplayAlert("Validation Error", "You must enter a Password", "OK");
return;
}
//We are good to go
else
{
IsBusy = true;
string APIServer = Application.Current.Properties["APIServer"].ToString();
var client = new RestClient(APIServer);
var request = new RestRequest("api/account/sign-in", Method.POST);
request.AddHeader("Content-type", "application/json");
request.AddJsonBody(new
{
email = Email,
password = Password }
);
var response = client.Execute(request) as RestResponse;
IsBusy = false;
//Valid response
if (response.StatusCode.ToString() == "OK")
{
var tokenobject = JsonConvert.DeserializeObject<TokenModel>(response.Content);
Application.Current.Properties["Token"] = tokenobject.Access_token;
string token = Application.Current.Properties["Token"].ToString();
App.Current.MainPage = new NavigationPage(new MainPage());
}
//Error response
else
{
var statuscode = response.StatusCode.ToString();
var content = response.Content;
var exception = response.ErrorException;
var error = response.ErrorMessage;
var statusdesc = response.StatusDescription;
await DisplayAlert("Login Failed", "Your login has failed. Please check your details and try again.", "OK");
}
}
}
}
公共类ViewModelBase:INotifyPropertyChanged
{
布尔很忙；
///
///获取或设置一个值，该值指示此实例是否正忙。
///
///如果此实例正忙，则为true；否则为false。
公共图书馆很忙
{
获取{return isBusy；}
设置
{
刚毛