Expender Header 与 Content互斥展示

Expender 在展开时，Header 不展示；不展开时，展示 Header

 <Expander dxlc:DockLayoutControl.Dock="Top" IsExpanded="True" ExpandDirection="Down" Name="expender"   >

            <Expander.Header>
                <dxlc:LayoutGroup Orientation="Horizontal"
                                  Visibility="{Binding IsExpanded,
                    RelativeSource={RelativeSource AncestorType={x:Type Expander},
                    Mode=FindAncestor},   Converter={StaticResource BoolToVisibilityConverter}}">

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResPatientEncounterId}">
                        <TextBlock  Text="{Binding ElementName=tbEncounterId, Path=Text}"
                                    TextWrapping="Wrap" FontSize="15" FontWeight="Bold"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem  Label="{StaticResource ResourceKey=ResPatientName}">
                        <TextBlock  MinWidth="200" Text="{Binding ElementName=tbPatientName, Path=Text}"
                                    TextWrapping="Wrap" FontSize="15" FontWeight="Bold"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem >
                        <TextBlock Name="tbAgeAndGender"
                                   TextWrapping="Wrap" FontSize="15" FontWeight="Bold"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResMRN}">
                        <TextBlock  Text="{Binding ElementName=tbMRN, Path=Text}"
                                   TextWrapping="Wrap" FontSize="15" FontWeight="Bold"></TextBlock>
                    </dxlc:LayoutItem>

                </dxlc:LayoutGroup>
            </Expander.Header>

            <dxlc:LayoutControl Orientation="Vertical" >

                <dxlc:LayoutGroup Orientation="Horizontal">

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResPatientEncounterId}">
                        <TextBlock Name="tbEncounterId"   ></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem  Label="{StaticResource ResourceKey=ResPatientName}">
                        <TextBlock Name="tbPatientName" MinWidth="200" TextWrapping="Wrap" ></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Name="liDateOfBirth" Label="{DynamicResource ResourceKey=ResDateOfBirthG}">
                        <TextBlock Name="tbDOB" TextWrapping="Wrap" ></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResAge}" Name="liAge">
                        <TextBlock Name="tbAge"  ></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResGender}" Name="liGender">
                        <TextBlock Name="tbGender" ></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResMRN}">
                        <TextBlock Name="tbMRN" ></TextBlock>
                    </dxlc:LayoutItem>

                </dxlc:LayoutGroup>

                <dxlc:LayoutGroup Orientation="Horizontal">

                    <dxlc:LayoutItem Label="{DynamicResource ResourceKey=ResAppointmentDoctor}">
                        <TextBlock Name="tbAttending"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResAllergies}">
                        <TextBlock Name="tbAllergies"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResAdvancedDirective}">
                        <TextBlock Name="tbAdavncedDirctive"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResWt}">
                        <TextBlock Name="tbWt"></TextBlock>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem Label="{DynamicResource ResResport}">
                        <TextBlock Name="tbReport"/>
                    </dxlc:LayoutItem>

                    <dxlc:LayoutItem >
                    </dxlc:LayoutItem>
                </dxlc:LayoutGroup>

            </dxlc:LayoutControl>
        </Expander>

 public class BoolToVisibilityConverter : IValueConverter
    {
        #region IValueConverter Members

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if ((bool)value)
                return Visibility.Collapsed;
            return Visibility.Visible;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if ((Visibility)value == Visibility.Visible)
                return false;
            return true;
        }

        #endregion
    }