diff --git a/AIStudio.Wpf.DiagramApp/Views/MainWindow.xaml b/AIStudio.Wpf.DiagramApp/Views/MainWindow.xaml
index a185b79..d9e15d8 100644
--- a/AIStudio.Wpf.DiagramApp/Views/MainWindow.xaml
+++ b/AIStudio.Wpf.DiagramApp/Views/MainWindow.xaml
@@ -2171,17 +2171,12 @@
                         <Fluent:SplitButton.LargeIcon>
                             <iconPacks:PackIconRemixIcon Kind="MindMap" VerticalAlignment="Center" HorizontalAlignment="Center"/>
                         </Fluent:SplitButton.LargeIcon>
-                        <ListBox x:Name="mindtype" Width="140" dd:EnumHelper.Enum="{x:Type dd:MindType}" SelectedItem="{Binding PageViewModel.DiagramViewModel.MindType,Mode=OneWay}">
+                        <ListBox x:Name="mindtype" Width="140" dd:EnumHelper.Enum="{x:Type dd:MindType}" SelectedItem="{Binding PageViewModel.DiagramViewModel.MindType}">
                             <ListBox.ItemTemplate>
                                 <DataTemplate>
                                     <TextBlock Text="{Binding .,Converter={StaticResource EnumDescriptionConverter}}" />
                                 </DataTemplate>
                             </ListBox.ItemTemplate>
-                            <i:Interaction.Triggers>
-                                <i:EventTrigger EventName="SelectionChanged">
-                                    <i:InvokeCommandAction Command="{Binding PageViewModel.DiagramViewModel.ChangeMindTypeCommand}" CommandParameter="{Binding ElementName=mindtype,Path=SelectedItem}"/>
-                                </i:EventTrigger>
-                            </i:Interaction.Triggers>
                         </ListBox>
                         <Fluent:SplitButton.ToolTip>
                             <Fluent:ScreenTip Title="MindType"
@@ -2193,7 +2188,7 @@
                         <Fluent:SplitButton.LargeIcon>
                             <iconPacks:PackIconUnicons Kind="Palette" Foreground="{Binding PageViewModel.DiagramViewModel.MindTheme,Converter={StaticResource MindThemeFillBrushConverter}}"  VerticalAlignment="Center" HorizontalAlignment="Center"/>
                         </Fluent:SplitButton.LargeIcon>
-                        <ListBox x:Name="mindtheme" dd:EnumHelper.Enum="{x:Type dd:MindTheme}" SelectedItem="{Binding PageViewModel.DiagramViewModel.MindTheme,Mode=OneWay}">
+                        <ListBox x:Name="mindtheme" dd:EnumHelper.Enum="{x:Type dd:MindTheme}" SelectedItem="{Binding PageViewModel.DiagramViewModel.MindTheme}">
                             <ListBox.ItemsPanel>
                                 <ItemsPanelTemplate>
                                     <UniformGrid Columns="2"/>
@@ -2206,11 +2201,6 @@
                                     </Border>
                                 </DataTemplate>
                             </ListBox.ItemTemplate>
-                            <i:Interaction.Triggers>
-                                <i:EventTrigger EventName="SelectionChanged">
-                                    <i:InvokeCommandAction Command="{Binding PageViewModel.DiagramViewModel.ChangeMindThemeCommand}" CommandParameter="{Binding ElementName=mindtheme,Path=SelectedItem}"/>
-                                </i:EventTrigger>
-                            </i:Interaction.Triggers>
                         </ListBox>
                         <Fluent:SplitButton.ToolTip>
                             <Fluent:ScreenTip Title="Theme"
diff --git a/AIStudio.Wpf.DiagramDesigner.Demo/ViewModels/Nodes/CustomDefinedDesignerItemViewModel.cs b/AIStudio.Wpf.DiagramDesigner.Demo/ViewModels/Nodes/CustomDefinedDesignerItemViewModel.cs
index 725c56e..d3e2ff2 100644
--- a/AIStudio.Wpf.DiagramDesigner.Demo/ViewModels/Nodes/CustomDefinedDesignerItemViewModel.cs
+++ b/AIStudio.Wpf.DiagramDesigner.Demo/ViewModels/Nodes/CustomDefinedDesignerItemViewModel.cs
@@ -41,8 +41,8 @@ namespace AIStudio.Wpf.DiagramDesigner.Demo.ViewModels
         {
             this.ItemWidth = 150;
             this.ItemHeight = 80;
-            connectors.Add(new FullyCreatedConnectorInfo(this, ConnectorOrientation.Top));
-            connectors.Add(new FullyCreatedConnectorInfo(this, ConnectorOrientation.Bottom));
+            AddConnector(new FullyCreatedConnectorInfo(this, ConnectorOrientation.Top));
+            AddConnector(new FullyCreatedConnectorInfo(this, ConnectorOrientation.Bottom));
         }
 
         protected override void LoadDesignerItemViewModel(SelectableItemBase designerbase)
diff --git a/AIStudio.Wpf.DiagramDesigner/UserControls/DiagramControl.xaml b/AIStudio.Wpf.DiagramDesigner/UserControls/DiagramControl.xaml
index 6673de3..a6125c6 100644
--- a/AIStudio.Wpf.DiagramDesigner/UserControls/DiagramControl.xaml
+++ b/AIStudio.Wpf.DiagramDesigner/UserControls/DiagramControl.xaml
@@ -207,7 +207,7 @@
 
             <ControlTemplate x:Key="ConnectorDecoratorTemplate"
                      TargetType="{x:Type Control}">
-                <Grid Margin="-5">
+                <Grid Margin="{Binding ConnectorMargin}">
                     <dd:Connector 
                         Content="{Binding LeftConnector}" 
                         Cursor="Cross"
diff --git a/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DesignerItemViewModelBase.cs b/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DesignerItemViewModelBase.cs
index f9665d7..87198f5 100644
--- a/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DesignerItemViewModelBase.cs
+++ b/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DesignerItemViewModelBase.cs
@@ -40,10 +40,10 @@ namespace AIStudio.Wpf.DiagramDesigner
 
         protected override void InitNew()
         {
-            connectors.Add(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Top));
-            connectors.Add(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Bottom));
-            connectors.Add(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Left));
-            connectors.Add(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Right));
+            AddConnector(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Top));
+            AddConnector(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Bottom));
+            AddConnector(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Left));
+            AddConnector(new FullyCreatedConnectorInfo(this.Root, this, ConnectorOrientation.Right));
         }
 
         protected override void LoadDesignerItemViewModel(SelectableItemBase designerbase)
@@ -221,7 +221,7 @@ namespace AIStudio.Wpf.DiagramDesigner
                     RaisePropertyChanged(nameof(PhysicalItemHeight));
                 }
             }
-        }
+        }       
 
         [DisplayName("ItemWidth(mm)")]
         [Browsable(true)]
@@ -265,6 +265,19 @@ namespace AIStudio.Wpf.DiagramDesigner
             }
         }
 
+        private double _connectorMargin = -4;
+        public double ConnectorMargin
+        {
+            get
+            {
+                return _connectorMargin;
+            }
+            set
+            {
+                SetProperty(ref _connectorMargin, value);
+            }
+        }
+
         private bool _showConnectors = false;
         public bool ShowConnectors
         {
@@ -573,6 +586,7 @@ namespace AIStudio.Wpf.DiagramDesigner
             if (!connectors.Contains(connector))
             {
                 connectors.Add(connector);
+                ConnectorMargin = 0 - connector.ConnectorWidth / 2;
             }
         }
 
diff --git a/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DiagramViewModel.cs b/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DiagramViewModel.cs
index 525b988..364fe7e 100644
--- a/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DiagramViewModel.cs
+++ b/AIStudio.Wpf.DiagramDesigner/ViewModels/BaseViewModel/DiagramViewModel.cs
@@ -1050,10 +1050,12 @@ namespace AIStudio.Wpf.DiagramDesigner
         {
             Mediator.Instance.Register(this);
             Items.CollectionChanged += Items_CollectionChanged;
+            
             var zoomValueChangedSubscription = WhenPropertyChanged.Where(o => o.ToString() == nameof(ZoomValue)).Throttle(TimeSpan.FromMilliseconds(100)).Subscribe(OnZoomValueChanged);//Sample
-           
+            this.PropertyChanged += DiagramViewModel_PropertyChanged;
             BuildMenuOptions();
         }
+
         public DiagramViewModel(DiagramItem diagramItem) : this()
         {
             DiagramType = diagramItem.DiagramType;
@@ -1161,6 +1163,11 @@ namespace AIStudio.Wpf.DiagramDesigner
         #endregion
 
         #region 属性改变
+        protected virtual void DiagramViewModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
+        {
+            
+        }
+
         private void Items_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
         {
             if (e.OldItems != null)
diff --git a/AIStudio.Wpf.Mind/Controls/ToolBoxControl.xaml b/AIStudio.Wpf.Mind/Controls/ToolBoxControl.xaml
index 625c573..c892d1d 100644
--- a/AIStudio.Wpf.Mind/Controls/ToolBoxControl.xaml
+++ b/AIStudio.Wpf.Mind/Controls/ToolBoxControl.xaml
@@ -416,32 +416,22 @@
             </TabItem>
             <TabItem Header="外观" Height="30" Width="50">
                 <StackPanel Orientation="Horizontal">
-                    <ComboBox x:Name="mindtype" dd:EnumHelper.Enum="{x:Type models:MindType}" SelectedItem="{Binding MindType, Mode=OneWay}" Style="{StaticResource FlatComboBoxStyle}">
+                    <ComboBox x:Name="mindtype" dd:EnumHelper.Enum="{x:Type models:MindType}" SelectedItem="{Binding MindType}" Style="{StaticResource FlatComboBoxStyle}">
                         <ComboBox.ItemTemplate>
                             <DataTemplate>
                                 <TextBlock Text="{Binding .,Converter={StaticResource EnumDescriptionConverter}}" VerticalAlignment="Center" />
                             </DataTemplate>
                         </ComboBox.ItemTemplate>
-                        <i:Interaction.Triggers>
-                            <i:EventTrigger EventName="SelectionChanged">
-                                <i:InvokeCommandAction Command="{Binding ChangeMindTypeCommand}" CommandParameter="{Binding ElementName=mindtype,Path=SelectedItem}"/>
-                            </i:EventTrigger>
-                        </i:Interaction.Triggers>
                     </ComboBox>
                     <Line Margin="2,0" X1="0" Y1="0" X2="0" Y2="100" StrokeDashArray="1" Stroke="Gray"  StrokeThickness="1"></Line>
-                    <ComboBox x:Name="mindtheme" dd:EnumHelper.Enum="{x:Type models:MindTheme}" SelectedItem="{Binding MindTheme, Mode=OneWay}" Style="{StaticResource FlatComboBox2ColumnStyle}">
+                    <ComboBox x:Name="mindtheme" dd:EnumHelper.Enum="{x:Type models:MindTheme}" SelectedItem="{Binding MindTheme}" Style="{StaticResource FlatComboBox2ColumnStyle}">
                         <ComboBox.ItemTemplate>
                             <DataTemplate>
                                 <Border CornerRadius="3" Background="{Binding .,Converter={StaticResource MindThemeFillBrushConverter}}" Padding="5">
                                     <TextBlock Foreground="{Binding .,Converter={StaticResource MindThemeFontBrushConverter}}" Text="{Binding .,Converter={StaticResource EnumDescriptionConverter}}" VerticalAlignment="Center" />
-                                </Border>                             
+                                </Border>
                             </DataTemplate>
                         </ComboBox.ItemTemplate>
-                        <i:Interaction.Triggers>
-                            <i:EventTrigger EventName="SelectionChanged">
-                                <i:InvokeCommandAction Command="{Binding ChangeMindThemeCommand}" CommandParameter="{Binding ElementName=mindtheme,Path=SelectedItem}"/>
-                            </i:EventTrigger>
-                        </i:Interaction.Triggers>
                     </ComboBox>
                     <Line Margin="2,0" X1="0" Y1="0" X2="0" Y2="100" StrokeDashArray="1" Stroke="Gray"  StrokeThickness="1"></Line>
                     <Button Style="{StaticResource FlatButtonStyle}" Command="{Binding ResetLayoutCommand}">
diff --git a/AIStudio.Wpf.Mind/Themes/MindNode.xaml b/AIStudio.Wpf.Mind/Themes/MindNode.xaml
index 903a4eb..0f651e4 100644
--- a/AIStudio.Wpf.Mind/Themes/MindNode.xaml
+++ b/AIStudio.Wpf.Mind/Themes/MindNode.xaml
@@ -40,7 +40,7 @@
     </Style>
 
     <ControlTemplate x:Key="MindNodeLevelStyle" TargetType="{x:Type ContentControl}">
-        <Grid>           
+        <Grid>
             <Grid.ContextMenu>
                 <ContextMenu ItemsSource="{Binding MenuOptions}">
                     <ContextMenu.ItemContainerStyle>
@@ -57,12 +57,12 @@
                 </ContextMenu>
             </Grid.ContextMenu>
 
-            <Grid>              
+            <Grid>
                 <Border BorderThickness="{Binding BorderThickness}" 
                         BorderBrush="{Binding ColorViewModel.LineColor,Converter={StaticResource ColorBrushConverter}}" 
                         Background="{Binding ColorViewModel.FillColor,Converter={StaticResource ColorBrushConverter}}"
                         CornerRadius="{Binding CornerRadius}"
-                        IsHitTestVisible="False">                   
+                        IsHitTestVisible="False">
                 </Border>
                 <Grid>
                     <Grid.RowDefinitions>
diff --git a/AIStudio.Wpf.Mind/ViewModels/IMindDiagramViewModel.cs b/AIStudio.Wpf.Mind/ViewModels/IMindDiagramViewModel.cs
index 36eacbd..85f386f 100644
--- a/AIStudio.Wpf.Mind/ViewModels/IMindDiagramViewModel.cs
+++ b/AIStudio.Wpf.Mind/ViewModels/IMindDiagramViewModel.cs
@@ -108,15 +108,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
         ICommand RemoveTagCommand
         {
             get;
-        }
-        ICommand ChangeMindTypeCommand
-        {
-            get;
-        }
-        ICommand ChangeMindThemeCommand
-        {
-            get;
-        }
+        }       
         ICommand ClearThemeCommand
         {
             get;
diff --git a/AIStudio.Wpf.Mind/ViewModels/MindDiagramViewModel.cs b/AIStudio.Wpf.Mind/ViewModels/MindDiagramViewModel.cs
index d4e2081..25454dd 100644
--- a/AIStudio.Wpf.Mind/ViewModels/MindDiagramViewModel.cs
+++ b/AIStudio.Wpf.Mind/ViewModels/MindDiagramViewModel.cs
@@ -24,10 +24,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
             }
             set
             {
-                if (!SetProperty(ref _mindType, value))
-                {
-                    RaisePropertyChanged(nameof(MindType));
-                }
+                SetProperty(ref _mindType, value);
             }
         }
 
@@ -40,10 +37,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
             }
             set
             {
-                if (!SetProperty(ref _mindTheme, value))
-                {
-                    RaisePropertyChanged(nameof(MindTheme));
-                }
+                SetProperty(ref _mindTheme, value);
             }
         }
 
@@ -310,24 +304,6 @@ namespace AIStudio.Wpf.Mind.ViewModels
             }
         }
 
-        private ICommand _changeMindTypeCommand;
-        public ICommand ChangeMindTypeCommand
-        {
-            get
-            {
-                return this._changeMindTypeCommand ?? (this._changeMindTypeCommand = new SimpleCommand(ExecuteEnable, this.ExecutedChangeMindTypeCommand));
-            }
-        }
-
-        private ICommand _changeMindThemeCommand;
-        public ICommand ChangeMindThemeCommand
-        {
-            get
-            {
-                return this._changeMindThemeCommand ?? (this._changeMindThemeCommand = new SimpleCommand(ExecuteEnable, this.ExecutedChangeMindThemeCommand));
-            }
-        }
-
         private ICommand _clearThemeCommand;
         public ICommand ClearThemeCommand
         {
@@ -445,27 +421,42 @@ namespace AIStudio.Wpf.Mind.ViewModels
         }
         #endregion
 
-        #region 属性改变
-        private bool isSelecting;
+        #region 属性改变 
+        protected override void DiagramViewModel_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
+        {
+            base.DiagramViewModel_PropertyChanged(sender, e);
+            if (e.PropertyName == nameof(MindType))
+            {
+                if (e is ValuePropertyChangedEventArgs valuePropertyChangedEventArgs)
+                {
+                    ChangeMindType((MindType)valuePropertyChangedEventArgs.OldValue, (MindType)valuePropertyChangedEventArgs.NewValue);
+                }
+            }
+            else if (e.PropertyName == nameof(MindTheme))
+            {
+                if (e is ValuePropertyChangedEventArgs valuePropertyChangedEventArgs)
+                {
+                    ChangeMindTheme((MindTheme)valuePropertyChangedEventArgs.OldValue, (MindTheme)valuePropertyChangedEventArgs.NewValue);
+                }
+            }
+        }
+
         protected override void Item_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
         {
             base.Item_PropertyChanged(sender, e);
             if (e.PropertyName == "IsSelected")
             {
-                isSelecting = true;
                 if (e is ValuePropertyChangedEventArgs valuePropertyChangedEventArgs)
                 {
                     LinkInfo = new LinkInfo(MindSelectedItem?.LinkInfo);
                     ImageInfo = new ImageInfo(MindSelectedItem?.ImageInfo);
                     Remark = MindSelectedItem?.Remark;
-                    if (MindSelectedItem != null)
-                    {
-                        MindType = MindSelectedItem.MindType;
-                        MindTheme = MindSelectedItem.MindTheme;
-                    }
+                    _mindType = MindSelectedItem?.MindType ?? RootItems.FirstOrDefault()?.MindType ?? MindType.Mind;
+                    _mindTheme = MindSelectedItem?.MindTheme ?? RootItems.FirstOrDefault()?.MindTheme ?? MindTheme.SkyBlue;
+                    RaisePropertyChanged(nameof(MindType));
+                    RaisePropertyChanged(nameof(MindTheme));
                 }
-                isSelecting = false;
-            }
+            }         
         }
         #endregion
 
@@ -711,8 +702,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
                 {
                     List<MindNode> newitems = new List<MindNode>();
                     DoCommandManager.DoNewCommand(this.ToString(),
-                    () => 
-                    {                        
+                    () => {
                         var content = window.ContentString;
                         var lines = content.Split(new string[] { "\n", "\r" }, StringSplitOptions.RemoveEmptyEntries);
                         MindNode lastnode = node;
@@ -1087,76 +1077,79 @@ namespace AIStudio.Wpf.Mind.ViewModels
         #endregion
 
         #region 改变模式，主题
-        private void ExecutedChangeMindTypeCommand(object obj)
+        private void ChangeMindType(MindType oldMindType, MindType newMindType)
         {
-            if (isSelecting) return;
-
-            var oldMindType = MindType;
-            if (obj is MindType mindType && mindType != oldMindType)
+            List<MindNode> roots;
+            if (RootItems.Count == 1)//只有一个的时候
             {
-                var roots = MindSelectedItems.Select(p => p.RootNode).Distinct().ToList();
-                if (roots.Count > 0)
-                {
-                    DoCommandManager.DoNewCommand(this.ToString(),
-                   () => {
-                       roots.ForEach(p => p.MindType = mindType);
-                       Items.OfType<MindNode>().ToList().ForEach(item => { item.InitLayout(true); });
-                       Items.OfType<MindNode>().ToList().ForEach(item => { item.InitConnectionLayout(); });
-                       roots.ForEach(p => p.UpdatedLayout());
-                   },
-                   () => {
-                       roots.ForEach(p => p.MindType = oldMindType);
-                       Items.OfType<MindNode>().ToList().ForEach(item => { item.InitLayout(true); });
-                       Items.OfType<MindNode>().ToList().ForEach(item => { item.InitConnectionLayout(); });
-                       roots.ForEach(p => p.UpdatedLayout());
-                   });
-                }
+                roots = RootItems.ToList();
+            }
+            else
+            {
+                roots = MindSelectedItems.Select(p => p.RootNode).Distinct().ToList();
+            }
+ 
+            if (roots.Count > 0)
+            {
+                DoCommandManager.DoNewCommand(this.ToString(),
+               () => {
+                   roots.ForEach(p => p.MindType = newMindType);
+                   roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.InitLayout(true); });
+                   roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.InitConnectionLayout(); });
+                   roots.ForEach(p => p.UpdatedLayout());
+               },
+               () => {
+                   roots.ForEach(p => p.MindType = oldMindType);
+                   roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.InitLayout(true); });
+                   roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.InitConnectionLayout(); });
+                   roots.ForEach(p => p.UpdatedLayout());
+               });
             }
         }
 
-
-        private void ExecutedChangeMindThemeCommand(object obj)
+        private void ChangeMindTheme(MindTheme oldMindTheme, MindTheme newMindTheme)
         {
-            if (isSelecting) return;
-
-            var oldmindTheme = MindTheme;
-            if (obj is MindTheme mindTheme && mindTheme != oldmindTheme)
+            List<MindNode> roots;
+            if (RootItems.Count == 1)//只有一个的时候
             {
-                var roots = MindSelectedItems.Select(p => p.RootNode).Distinct().ToList();
-                if (roots.Count > 0)
-                {
-                    DoCommandManager.DoNewCommand(this.ToString(),
-                    () => {
-                        var mindThemeModel = MindThemeHelper.GetTheme(mindTheme);
-                        if (mindThemeModel?.Dark == true)
-                        {
-                            PageBackground = Colors.Black;
-                        }
-                        else
-                        {
-                            PageBackground = Colors.White;
-                        }
-                        MindTheme = mindTheme;
-                        roots.ForEach(p => p.MindTheme = MindTheme);
-                        roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.ThemeChange(); });
-                        roots.ForEach(p => p.UpdatedLayout());
-                    },
-                    () => {
-                        var mindThemeModel = MindThemeHelper.GetTheme(oldmindTheme);
-                        if (mindThemeModel?.Dark == true)
-                        {
-                            PageBackground = Colors.Black;
-                        }
-                        else
-                        {
-                            PageBackground = Colors.White;
-                        }
-                        MindTheme = oldmindTheme;
-                        roots.ForEach(p => p.MindTheme = MindTheme);
-                        roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.ThemeChange(); });
-                        roots.ForEach(p => p.UpdatedLayout());
-                    });
-                }
+                roots = RootItems.ToList();
+            }
+            else
+            {
+                roots = MindSelectedItems.Select(p => p.RootNode).Distinct().ToList();
+            }
+
+            if (roots.Count > 0)
+            {
+                DoCommandManager.DoNewCommand(this.ToString(),
+                () => {
+                    var mindThemeModel = MindThemeHelper.GetTheme(newMindTheme);
+                    if (mindThemeModel?.Dark == true)
+                    {
+                        PageBackground = Colors.Black;
+                    }
+                    else
+                    {
+                        PageBackground = Colors.White;
+                    }
+                    roots.ForEach(p => p.MindTheme = newMindTheme);
+                    roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.ThemeChange(); });
+                    roots.ForEach(p => p.UpdatedLayout());
+                },
+                () => {
+                    var mindThemeModel = MindThemeHelper.GetTheme(oldMindTheme);
+                    if (mindThemeModel?.Dark == true)
+                    {
+                        PageBackground = Colors.Black;
+                    }
+                    else
+                    {
+                        PageBackground = Colors.White;
+                    }
+                    roots.ForEach(p => p.MindTheme = oldMindTheme);
+                    roots.SelectMany(p => p.GetChildren(true)).ToList().ForEach(item => { item.ThemeChange(); });
+                    roots.ForEach(p => p.UpdatedLayout());
+                });
             }
         }
 
diff --git a/AIStudio.Wpf.Mind/ViewModels/MindNode.cs b/AIStudio.Wpf.Mind/ViewModels/MindNode.cs
index 60b85da..e9a8ce7 100644
--- a/AIStudio.Wpf.Mind/ViewModels/MindNode.cs
+++ b/AIStudio.Wpf.Mind/ViewModels/MindNode.cs
@@ -77,6 +77,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
             EnabledForConnection = false;
             AlwayForResized = true;
             CustomText = true;
+            IsInnerConnector = true;
 
             AddChildCommand = (Root as IMindDiagramViewModel)?.AddChildCommand;
             AddParentCommand = (Root as IMindDiagramViewModel)?.AddParentCommand;
@@ -100,8 +101,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
             var layout = TypeHelper.GetType(this.MindType.ToString() + "Layout");
             MindLayout = layout != null ? (System.Activator.CreateInstance(layout) as IMindLayout) : new MindLayout();
 
-            this.PropertyChanged -= this.Item_PropertyChanged;
-            IsInnerConnector = true;
+            this.PropertyChanged -= this.Item_PropertyChanged;      
             MindLayout.Appearance(this, MindTheme, initAppearance);
             this.PropertyChanged += this.Item_PropertyChanged;
         }
@@ -348,6 +348,7 @@ namespace AIStudio.Wpf.Mind.ViewModels
         }
 
         private string _remark;
+        [Browsable(true)]
         public string Remark
         {
             get