remove RelativePanel

This would be included in WinUI 3.0, which MS plans to make open source.
[LINK](https://github.com/Microsoft/microsoft-ui-xaml/issues/36#issuecomment-492910592)

src/Core_30/HandyControlDemo_Core_30/HandyControlDemo_Core30.csproj

@@ -350,9 +350,6 @@
     <Resource Include="..\..\Shared\HandyControlDemo_Shared\Resources\Img\LeftMainContent\brackets_Square_16xLG.png">
       <Link>Resources\Img\LeftMainContent\brackets_Square_16xLG.png</Link>
     </Resource>
-    <Resource Include="..\..\Shared\HandyControlDemo_Shared\Resources\Img\LeftMainContent\PaneLayout_16x.png">
-      <Link>Resources\Img\LeftMainContent\PaneLayout_16x.png</Link>
-    </Resource>
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="..\..\Shared\HandyControlDemo_Shared\Properties\Langs\Lang.en.resx">

src/Net_40/HandyControlDemo_Net_40/HandyControlDemo_Net_40.csproj

@@ -395,9 +395,6 @@
       <Generator>TextTemplatingFileGenerator</Generator>
       <LastGenOutput>MessageToken.cs</LastGenOutput>
     </Content>
-    <Resource Include="..\..\Shared\HandyControlDemo_Shared\Resources\Img\LeftMainContent\PaneLayout_16x.png">
-      <Link>Resources\Img\LeftMainContent\PaneLayout_16x.png</Link>
-    </Resource>
     <Resource Include="..\..\Shared\HandyControlDemo_Shared\Resources\Img\LeftMainContent\brackets_Square_16xLG.png">
       <Link>Resources\Img\LeftMainContent\brackets_Square_16xLG.png</Link>
     </Resource>

src/Shared/HandyControlDemo_Shared/Data/MessageToken.cs

@@ -98,8 +98,6 @@
 	
         public static readonly string RangeSliderDemoCtl = nameof(RangeSliderDemoCtl);
 	
-        public static readonly string RelativePanelDemoCtl = nameof(RelativePanelDemoCtl);
-	
         public static readonly string ButtonDemoCtl = nameof(ButtonDemoCtl);
 
         public static readonly string RepeatButtonDemoCtl = nameof(RepeatButtonDemoCtl);

src/Shared/HandyControlDemo_Shared/Data/MessageToken.tt

@@ -51,8 +51,7 @@ var controlList = new List<string>
 	"DialogDemoCtl",
 	"SideMenuDemoCtl",
 	"GridDemoCtl",
-	"RangeSliderDemoCtl",
+	"RangeSliderDemoCtl"
-	"RelativePanelDemoCtl"
 };
 var styleList = new List<string>
 {

src/Shared/HandyControlDemo_Shared/UserControl/Main/LeftMainContent.xaml

@@ -325,11 +325,6 @@
                                 <Image Source="../../Resources/Img/LeftMainContent/Panel_16x.png"/>
                             </hc:EdgeElement.LeftContent>
                         </ListBoxItem>
-                        <ListBoxItem Style="{StaticResource ListBoxItemNew}" Tag="{x:Static data:MessageToken.RelativePanelDemoCtl}" Content="{x:Static langs:Lang.RelativePanel}">
-                            <hc:EdgeElement.LeftContent>
-                                <Image Source="../../Resources/Img/LeftMainContent/PaneLayout_16x.png"/>
-                            </hc:EdgeElement.LeftContent>
-                        </ListBoxItem>
                         <ListBoxItem Tag="{x:Static data:MessageToken.CoverViewDemoCtl}" Content="{x:Static langs:Lang.CoverView}">
                             <hc:EdgeElement.LeftContent>
                                 <Image Source="../../Resources/Img/LeftMainContent/DetailDataView_16x.png"/>

src/Shared/HandyControl_Shared/Controls/Panel/RelativePanel.cs

@@ -1,132 +0,0 @@
-using System.ComponentModel;
-using System.Windows;
-using System.Windows.Controls;
-using HandyControl.Tools.Converter;
-
-namespace HandyControl.Controls
-{
-    public class RelativePanel : Panel
-    {
-        public static readonly DependencyProperty AboveProperty = DependencyProperty.RegisterAttached(
-            "Above", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAbove(DependencyObject element, DependencyObject value) => element.SetValue(AboveProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAbove(DependencyObject element) => (DependencyObject)element.GetValue(AboveProperty);
-
-        public static readonly DependencyProperty AlignBottomWithProperty = DependencyProperty.RegisterAttached(
-            "AlignBottomWith", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAlignBottomWith(DependencyObject element, DependencyObject value) => element.SetValue(AlignBottomWithProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAlignBottomWith(DependencyObject element) => (DependencyObject)element.GetValue(AlignBottomWithProperty);
-
-        public static readonly DependencyProperty AlignBottomWithPanelProperty = DependencyProperty.RegisterAttached(
-            "AlignBottomWithPanel", typeof(bool), typeof(RelativePanel), new PropertyMetadata(default(bool)));
-
-        public static void SetAlignBottomWithPanel(DependencyObject element, bool value) => element.SetValue(AlignBottomWithPanelProperty, value);
-
-        public static bool GetAlignBottomWithPanel(DependencyObject element) => (bool)element.GetValue(AlignBottomWithPanelProperty);
-
-        public static readonly DependencyProperty AlignHorizontalCenterWithProperty = DependencyProperty.RegisterAttached(
-            "AlignHorizontalCenterWith", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAlignHorizontalCenterWith(DependencyObject element, DependencyObject value) => element.SetValue(AlignHorizontalCenterWithProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAlignHorizontalCenterWith(DependencyObject element) => (DependencyObject)element.GetValue(AlignHorizontalCenterWithProperty);
-
-        public static readonly DependencyProperty AlignHorizontalCenterWithPanelProperty = DependencyProperty.RegisterAttached(
-            "AlignHorizontalCenterWithPanel", typeof(bool), typeof(RelativePanel), new PropertyMetadata(default(bool)));
-
-        public static void SetAlignHorizontalCenterWithPanel(DependencyObject element, bool value) => element.SetValue(AlignHorizontalCenterWithPanelProperty, value);
-
-        public static bool GetAlignHorizontalCenterWithPanel(DependencyObject element) => (bool)element.GetValue(AlignHorizontalCenterWithPanelProperty);
-
-        public static readonly DependencyProperty AlignLeftWithProperty = DependencyProperty.RegisterAttached(
-            "AlignLeftWith", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAlignLeftWith(DependencyObject element, DependencyObject value) => element.SetValue(AlignLeftWithProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAlignLeftWith(DependencyObject element) => (DependencyObject)element.GetValue(AlignLeftWithProperty);
-
-        public static readonly DependencyProperty AlignLeftWithPanelProperty = DependencyProperty.RegisterAttached(
-            "AlignLeftWithPanel", typeof(bool), typeof(RelativePanel), new PropertyMetadata(default(bool)));
-
-        public static void SetAlignLeftWithPanel(DependencyObject element, bool value) => element.SetValue(AlignLeftWithPanelProperty, value);
-
-        public static bool GetAlignLeftWithPanel(DependencyObject element) => (bool)element.GetValue(AlignLeftWithPanelProperty);
-
-        public static readonly DependencyProperty AlignRightWithProperty = DependencyProperty.RegisterAttached(
-            "AlignRightWith", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAlignRightWith(DependencyObject element, DependencyObject value) => element.SetValue(AlignRightWithProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAlignRightWith(DependencyObject element) => (DependencyObject)element.GetValue(AlignRightWithProperty);
-
-        public static readonly DependencyProperty AlignRightWithPanelProperty = DependencyProperty.RegisterAttached(
-            "AlignRightWithPanel", typeof(bool), typeof(RelativePanel), new PropertyMetadata(default(bool)));
-
-        public static void SetAlignRightWithPanel(DependencyObject element, bool value) => element.SetValue(AlignRightWithPanelProperty, value);
-
-        public static bool GetAlignRightWithPanel(DependencyObject element) => (bool)element.GetValue(AlignRightWithPanelProperty);
-
-        public static readonly DependencyProperty AlignTopWithProperty = DependencyProperty.RegisterAttached(
-            "AlignTopWith", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAlignTopWith(DependencyObject element, DependencyObject value) => element.SetValue(AlignTopWithProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAlignTopWith(DependencyObject element) => (DependencyObject)element.GetValue(AlignTopWithProperty);
-
-        public static readonly DependencyProperty AlignTopWithPanelProperty = DependencyProperty.RegisterAttached(
-            "AlignTopWithPanel", typeof(bool), typeof(RelativePanel), new PropertyMetadata(default(bool)));
-
-        public static void SetAlignTopWithPanel(DependencyObject element, bool value) => element.SetValue(AlignTopWithPanelProperty, value);
-
-        public static bool GetAlignTopWithPanel(DependencyObject element) => (bool)element.GetValue(AlignTopWithPanelProperty);
-
-        public static readonly DependencyProperty AlignVerticalCenterWithProperty = DependencyProperty.RegisterAttached(
-            "AlignVerticalCenterWith", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetAlignVerticalCenterWith(DependencyObject element, DependencyObject value) => element.SetValue(AlignVerticalCenterWithProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetAlignVerticalCenterWith(DependencyObject element) => (DependencyObject)element.GetValue(AlignVerticalCenterWithProperty);
-
-        public static readonly DependencyProperty AlignVerticalCenterWithPanelProperty = DependencyProperty.RegisterAttached(
-            "AlignVerticalCenterWithPanel", typeof(bool), typeof(RelativePanel), new PropertyMetadata(default(bool)));
-
-        public static void SetAlignVerticalCenterWithPanel(DependencyObject element, bool value) => element.SetValue(AlignVerticalCenterWithPanelProperty, value);
-
-        public static bool GetAlignVerticalCenterWithPanel(DependencyObject element) => (bool)element.GetValue(AlignVerticalCenterWithPanelProperty);
-
-        public static readonly DependencyProperty BelowProperty = DependencyProperty.RegisterAttached(
-            "Below", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetBelow(DependencyObject element, DependencyObject value) => element.SetValue(BelowProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetBelow(DependencyObject element) => (DependencyObject)element.GetValue(BelowProperty);
-
-        public static readonly DependencyProperty LeftOfProperty = DependencyProperty.RegisterAttached(
-            "LeftOf", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetLeftOf(DependencyObject element, DependencyObject value) => element.SetValue(LeftOfProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetLeftOf(DependencyObject element) => (DependencyObject)element.GetValue(LeftOfProperty);
-
-        public static readonly DependencyProperty RightOfProperty = DependencyProperty.RegisterAttached(
-            "RightOf", typeof(DependencyObject), typeof(RelativePanel), new PropertyMetadata(default(DependencyObject)));
-
-        public static void SetRightOf(DependencyObject element, DependencyObject value) => element.SetValue(RightOfProperty, value);
-
-        [TypeConverter(typeof(NameReferenceConverter))]
-        public static DependencyObject GetRightOf(DependencyObject element) => (DependencyObject)element.GetValue(RightOfProperty);
-    }
-}

src/Shared/HandyControl_Shared/Data/Enum/RelativeStatus.cs

@@ -1,37 +0,0 @@
-namespace HandyControl_Shared.Data.Enum
-{
-    public enum RelativeStatus
-    {
-        LeftOf,
-
-        Above,
-
-        RightOf,
-
-        Below,
-
-        AlignLeftWith,
-
-        AlignTopWith,
-
-        AlignRightWith,
-
-        AlignBottomWith,
-
-        AlignHorizontalCenterWith,
-
-        AlignVerticalCenterWith,
-
-        AlignLeftWithPanel,
-
-        AlignTopWithPanel,
-
-        AlignRightWithPanel,
-
-        AlignBottomWithPanel,
-
-        AlignHorizontalCenterWithPanel,
-
-        AlignVerticalCenterWithPanel
-    }
-}

src/Shared/HandyControl_Shared/HandyControl_Shared.projitems

@@ -18,11 +18,9 @@
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Attach\InfoElement.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Attach\PanelElement.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Attach\PasswordBoxAttach.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)Controls\Panel\RelativePanel.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Slider\RangeSlider\RangeTrack.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Slider\RangeSlider\RangeThumb.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Controls\Slider\RangeSlider\TwoWayRangeBase.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)Data\Enum\RelativeStatus.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interactivity\Commands\OpenLinkCommand.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Tools\Converter\NameReferenceConverter.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Tools\Extension\StringExtension.cs" />