Added TipCalc Sample

Samples/Program.cs

@@ -31,6 +31,7 @@ namespace Samples
             new FilesSample ().Publish ();
             new DisplayAlertSample ().Publish ();
             new EditorSample().Publish();
+            new TipCalcSample().Publish();
             new XuzzleSample().Publish();
 
             UI.Present ("/display-alert");

Samples/Samples.csproj

@@ -38,6 +38,9 @@
     <EmbeddedResource Update="DisplayAlertPage.xaml">
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
+    <EmbeddedResource Update="TipCalc\TipCalcPage.xaml">
+      <Generator>MSBuild:Compile</Generator>
+    </EmbeddedResource>
     <EmbeddedResource Update="XamlPreviewPage.xaml">
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
@@ -46,10 +49,7 @@
   <ItemGroup>
     <None Remove="BugSweeper\Images\RedBug.png" />
     <None Remove="BugSweeper\Images\Xamarin120.png" />
-  </ItemGroup>
+    <None Remove="TipCalc\TipCalcPage.xaml" />
-    
-  <ItemGroup>
-    <Folder Include="TipCalc\" />
   </ItemGroup>
   <PropertyGroup>
     <OutputType>Exe</OutputType>

Samples/TipCalc/DoubleRoundingConverter.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Globalization;
+using Xamarin.Forms;
+
+namespace TipCalc
+{
+    public class DoubleRoundingConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType,
+                              object parameter, CultureInfo culture)
+        {
+            return Round((double)value, parameter);
+        }
+
+        public object ConvertBack(object value, Type targetType,
+                                  object parameter, CultureInfo culture)
+        {
+            return Round((double)value, parameter);
+        }
+
+        double Round(double number, object parameter)
+        {
+            double precision = 1;
+
+            // Assume parameter is string encoding precision.
+            if (parameter != null)
+            {
+                precision = Double.Parse((string)parameter);
+            }
+            return precision * Math.Round(number / precision);
+        }
+    }
+}

Samples/TipCalc/DoubleToStringConverter.cs

@@ -0,0 +1,32 @@
+using System;
+using System.Globalization;
+using Xamarin.Forms;
+
+namespace TipCalc
+{
+    public class DoubleToStringConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, 
+                              object parameter, CultureInfo culture)
+        {
+            // Assumes value is double.
+            double number = (double)value;
+
+            // Return empty string for a zero (good for Entry views).
+            if (number == 0)
+            {
+                return "";
+            }
+
+            return number.ToString();
+        }
+
+        public object ConvertBack(object value, Type targetType, 
+                                  object parameter, CultureInfo culture)
+        {
+            double number = 0;
+            Double.TryParse((string)value, out number);
+            return number;
+        }
+    }
+}

Samples/TipCalc/TipCalcModel.cs

@@ -0,0 +1,111 @@
+using System;
+using System.ComponentModel;
+
+namespace TipCalc
+{
+    class TipCalcModel : INotifyPropertyChanged
+    {
+        double subTotal, postTaxTotal, tipPercent, tipAmount, total;
+
+        public event PropertyChangedEventHandler PropertyChanged;
+
+        public double SubTotal
+        {
+            set
+            {
+                 if (subTotal != value)
+                 {
+                     subTotal = value;
+                     OnPropertyChanged("SubTotal");
+                     Recalculate();
+                 }
+            }
+            get
+            {
+                return subTotal;
+            }
+        }
+
+        public double PostTaxTotal
+        {
+            set
+            {
+                if (postTaxTotal != value)
+                {
+                    postTaxTotal = value;
+                    OnPropertyChanged("PostTaxTotal");
+                    Recalculate();
+                }
+            }
+            get
+            {
+                return postTaxTotal;
+            }
+        }
+
+        public double TipPercent
+        {
+            set
+            {
+                if (tipPercent != value)
+                {
+                    tipPercent = value;
+                    OnPropertyChanged("TipPercent");
+                    Recalculate();
+                }
+            }
+            get
+            {
+                return tipPercent;
+            }
+        }
+
+        public double TipAmount
+        {
+            set
+            {
+                if (tipAmount != value)
+                {
+                    tipAmount = value;
+                    OnPropertyChanged("TipAmount");
+                }
+            }
+            get
+            {
+                return tipAmount;
+            }
+        }
+
+        public double Total
+        {
+            set
+            {
+                if (total != value)
+                {
+                    total = value;
+                    OnPropertyChanged("Total");
+                }
+            }
+            get
+            {
+                return total;
+            }
+        }
+
+        void Recalculate()
+        {
+            this.TipAmount = Math.Round(this.TipPercent * this.SubTotal / 100, 2);
+
+            // Round total to nearest quarter.
+            this.Total = Math.Round(4 * (this.PostTaxTotal + this.TipAmount)) / 4;
+        }
+
+        protected void OnPropertyChanged(string propertyName)
+        {
+            if (PropertyChanged != null)
+            {
+                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
+            }
+        }
+    }
+}

Samples/TipCalc/TipCalcPage.xaml

@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="utf-8"?>
+<ContentPage 
+    xmlns="http://xamarin.com/schemas/2014/forms" 
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" 
+    xmlns:local="clr-namespace:TipCalc" 
+    x:Class="TipCalc.TipCalcPage">
+    <ContentPage.Padding>
+        <OnPlatform x:TypeArguments="Thickness">
+            <On Platform="iOS" Value="5, 20, 5, 0" />
+            <On Platform="Android, UWP, WinRT, WinPhone" Value="5, 0, 5, 0" />
+        </OnPlatform>
+    </ContentPage.Padding>
+    <ContentPage.Resources>
+        <ResourceDictionary>
+            <local:TipCalcModel x:Key="model" TipPercent="15" />
+            <local:DoubleToStringConverter x:Key="stringConverter" />
+            <local:DoubleRoundingConverter x:Key="roundConverter" />
+        </ResourceDictionary>
+    </ContentPage.Resources>
+    <Grid BindingContext="{StaticResource model}">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="Auto" />
+        </Grid.RowDefinitions>
+        <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="*" />
+            <ColumnDefinition Width="*" />
+        </Grid.ColumnDefinitions>
+        <!-- Row 0 -->
+        <Label Text="Food &amp; Drink:" Grid.Row="0" Grid.Column="0" Font="Large" HorizontalTextAlignment="End" VerticalTextAlignment="Center" />
+        <Entry Grid.Row="0" Grid.Column="1" Keyboard="Numeric" Placeholder="Subtotal" Text="{Binding SubTotal, &#xA;                           Converter={StaticResource stringConverter}}" />
+        <!-- Row 1 -->
+        <Label Text="Total after Tax:" Grid.Row="1" Grid.Column="0" Font="Large" HorizontalTextAlignment="End" VerticalTextAlignment="Center" />
+        <Entry Grid.Row="1" Grid.Column="1" Keyboard="Numeric" Placeholder="Receipt total" Text="{Binding PostTaxTotal,&#xA;                          Converter={StaticResource stringConverter}}" />
+        <!-- Row 2 -->
+        <Label Text="Tip Percent:" Grid.Row="2" Grid.Column="0" Font="Large" HorizontalTextAlignment="End" VerticalTextAlignment="Center" />
+        <Entry Grid.Row="2" Grid.Column="1" Keyboard="Numeric" Text="{Binding TipPercent,&#xA;                          Converter={StaticResource stringConverter}}" />
+        <!-- Row 3 -->
+        <Slider Grid.Row="3" Grid.Column="0" Grid.ColumnSpan="2" Minimum="0" Maximum="100" Value="{Binding TipPercent,&#xA;                            Mode=TwoWay,&#xA;                            Converter={StaticResource roundConverter},&#xA;                            ConverterParameter=0.5}" />
+        <!-- Row 4 -->
+        <Label Text="Tip Amount:" Grid.Row="4" Grid.Column="0" Font="Large" HorizontalTextAlignment="End" VerticalTextAlignment="Center" />
+        <ContentView BackgroundColor="#40808080" Grid.Row="4" Grid.Column="1" Padding="10, 10, 40, 10">
+            <Label Text="{Binding TipAmount,&#xA;                            StringFormat='{0:C}'}" Font="Large" HorizontalTextAlignment="End" />
+        </ContentView>
+        <!-- Row 5 -->
+        <Label Text="Total:" Grid.Row="5" Grid.Column="0" Font="Large" HorizontalTextAlignment="End" VerticalTextAlignment="Center" />
+        <ContentView BackgroundColor="#40808080" Grid.Row="5" Grid.Column="1" Padding="10, 10, 40, 10">
+            <Label Text="{Binding Total, &#xA;                              StringFormat='{0:C}'}" Font="Large" HorizontalTextAlignment="End" />
+        </ContentView>
+    </Grid>
+</ContentPage>

Samples/TipCalc/TipCalcPage.xaml.cs

@@ -0,0 +1,10 @@
+namespace TipCalc
+{
+    public partial class TipCalcPage
+    {
+        public TipCalcPage()
+        {
+            InitializeComponent();
+        }
+    }
+}

Samples/TipCalcSample.cs

@@ -0,0 +1,21 @@
+using Ooui;
+using Xamarin.Forms;
+
+namespace Samples
+{
+    public class TipCalcSample : ISample
+    {
+        public string Title => "Xamarin.Forms TipCalc";
+
+        public Ooui.Element CreateElement()
+        {
+            var page = new TipCalc.TipCalcPage();
+            return page.GetOouiElement();
+        }
+
+        public void Publish()
+        {
+            UI.Publish("/tipcalc", CreateElement);
+        }
+    }
+}