C＃在另一个计时器内使用计时器？(C# using a timer within another timer?)

 下面的代码是一个Xamarin.Forms谷歌材料设计，如入门方法。 总xaml +一点编码:) 
 
 第1步：在PCL项目中创建一个类 
 
public class CustomEntry : Entry
    {

    }
 
 第2步：在App.xaml中创建一个控件模板 
 
<ControlTemplate x:Key="MyControlTemplate">
    <Grid>
      <Grid.RowDefinitions>
        <RowDefinition Height="Auto"/>
        <RowDefinition Height="Auto"/>
      </Grid.RowDefinitions>
      <controls:CustomEntry x:Name="myEntry" Text="{TemplateBinding Text, Mode=TwoWay}" HorizontalOptions="FillAndExpand" HorizontalTextAlignment="Start" IsPassword="{TemplateBinding IsPassword}" MinimumHeightRequest="25"/>
      <BoxView Grid.Row="1" BackgroundColor="#D2D2D2" HeightRequest="1" HorizontalOptions="FillAndExpand" VerticalOptions="Start">
        <BoxView.Triggers>
          <DataTrigger TargetType="BoxView" Binding="{Binding Source={x:Reference myEntry}, Path=IsFocused}" Value="true">
            <Setter Property="BackgroundColor" Value="Black" />
            <Setter Property="HeightRequest" Value="2"/>
          </DataTrigger>
        </BoxView.Triggers>
      </BoxView>
    </Grid>
  </ControlTemplate>  
 
 第3步：创建超级材料设计入口类 
 
public class MyMaterialDesignEntry : ContentView, INotifyPropertyChanged
    {
        public static readonly BindableProperty TextProperty =
        BindableProperty.Create("Text", typeof(string), typeof(ContentPage), "");
        public static readonly BindableProperty IsPasswordProperty =
        BindableProperty.Create("IsPassword", typeof(bool), typeof(ContentPage), false);

        public string Text
        {
            get { return (string)GetValue(TextProperty); }
            set { SetValue(TextProperty, (string)value); }
        }       

        public bool IsPassword => (bool)GetValue(IsPasswordProperty);

        public MyMaterialDesignEntry()
        {
            ControlTemplate = (ControlTemplate)Application.Current.Resources.FirstOrDefault(x => x.Key == "MyControlTemplate").Value;
        }      
    }
 
 第4步：在xaml中使用超级材质设计条目 
 
<StackLayout Orientation="Vertical" HorizontalOptions="FillAndExpand">
            <Label Text="Login"/>
            <controls:MyMaterialDesignEntry Text="{Binding Login, Mode=TwoWay}"/>
          </StackLayout>
 
 不要忘记在页面xaml中添加适当的命名空间。 无论如何它会告诉你的。 

Below code is a Xamarin.Forms google material design like entry approach. Total xaml + a little coding :)
 
Step1: Create a class in PCL project
 
public class CustomEntry : Entry
    {

    }
 
Step2: Create a control template in App.xaml
 
<ControlTemplate x:Key="MyControlTemplate">
    <Grid>
      <Grid.RowDefinitions>
        <RowDefinition Height="Auto"/>
        <RowDefinition Height="Auto"/>
      </Grid.RowDefinitions>
      <controls:CustomEntry x:Name="myEntry" Text="{TemplateBinding Text, Mode=TwoWay}" HorizontalOptions="FillAndExpand" HorizontalTextAlignment="Start" IsPassword="{TemplateBinding IsPassword}" MinimumHeightRequest="25"/>
      <BoxView Grid.Row="1" BackgroundColor="#D2D2D2" HeightRequest="1" HorizontalOptions="FillAndExpand" VerticalOptions="Start">
        <BoxView.Triggers>
          <DataTrigger TargetType="BoxView" Binding="{Binding Source={x:Reference myEntry}, Path=IsFocused}" Value="true">
            <Setter Property="BackgroundColor" Value="Black" />
            <Setter Property="HeightRequest" Value="2"/>
          </DataTrigger>
        </BoxView.Triggers>
      </BoxView>
    </Grid>
  </ControlTemplate>  
 
Step 3: Create a super material design entry class
 
public class MyMaterialDesignEntry : ContentView, INotifyPropertyChanged
    {
        public static readonly BindableProperty TextProperty =
        BindableProperty.Create("Text", typeof(string), typeof(ContentPage), "");
        public static readonly BindableProperty IsPasswordProperty =
        BindableProperty.Create("IsPassword", typeof(bool), typeof(ContentPage), false);

        public string Text
        {
            get { return (string)GetValue(TextProperty); }
            set { SetValue(TextProperty, (string)value); }
        }       

        public bool IsPassword => (bool)GetValue(IsPasswordProperty);

        public MyMaterialDesignEntry()
        {
            ControlTemplate = (ControlTemplate)Application.Current.Resources.FirstOrDefault(x => x.Key == "MyControlTemplate").Value;
        }      
    }
 
Step 4: Use your super material design entry in xaml
 
<StackLayout Orientation="Vertical" HorizontalOptions="FillAndExpand">
            <Label Text="Login"/>
            <controls:MyMaterialDesignEntry Text="{Binding Login, Mode=TwoWay}"/>
          </StackLayout>
 
Don't forget to add appropriate namespaces to your page xaml. It will tell you anyway.