tcp连接逻辑

添加登录动画

View/LogPage.xaml

@@ -3,6 +3,7 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
              x:Class="SunlightAggregationTerminal.View.LogPage"
              Title="登录">
+    <Grid>
     <VerticalStackLayout Padding="30" Spacing="10" 
             VerticalOptions="Center" 
             HorizontalOptions="Center"
@@ -75,4 +76,20 @@
                 Margin="0,10,0,0"
                 Clicked="Log_Clicked"/>
     </VerticalStackLayout>
+        <Grid x:Name="LoadingIndicator" BackgroundColor="Gray" 
+              IsVisible="False">
+            <VerticalStackLayout Padding="30" Spacing="10"       
+                                 VerticalOptions="Center"       
+                                 HorizontalOptions="Center">
+                <ActivityIndicator IsRunning="True"    
+                               Color="Blue"  
+                               HorizontalOptions="Center"   
+                               VerticalOptions="Center" />
+            <Label Text="登录中..."
+                   FontAttributes="Bold"
+                   FontSize="24" 
+                   TextColor="Black"/>
+            </VerticalStackLayout>
+        </Grid>
+    </Grid>
 </ContentPage>

View/LogPage.xaml.cs

@@ -70,10 +70,12 @@ public partial class LogPage : ContentPage
 
     private async void Log_Clicked(object sender, EventArgs e)//登录
     {
-        TcpServer.Configuration(SERVERIP.Text, UsernameEntry.Text, PasswordEntry.Text, 
+        TcpServer.Configuration(SERVERIP.Text, UsernameEntry.Text, PasswordEntry.Text,
             Models.AppModels.GetAppUniqueId());
 
-        if (await AppModels.LogIn()) 
+        LoadingIndicator.IsVisible = true;
+
+        if (await AppModels.LogIn())
         {
             var temp_name = AppModels.Select("SELECT * FROM  Users WHERE User='" + UsernameEntry.Text + "' LIMIT 1;")!.Tables[0];
             if (temp_name != null)
@@ -104,8 +106,14 @@ public partial class LogPage : ContentPage
                       App.GlobalData.ServerID + "');";
                 AppModels.INSERT(sql);
             }
+
+            await Navigation.PopModalAsync();
         }
-        await Navigation.PopModalAsync();
+        else 
+        {
+            await DisplayAlertAsync("未登录", "服务器不存在或拒绝访问", "是");
+        }
+        LoadingIndicator.IsVisible = false;
     }