右下角擴展區域也會執行MouseEnter事件

            <Grid x:Name="gridMain" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
                <Grid.RowDefinitions>
                    <RowDefinition Height="100"/>
                    <RowDefinition Height="*"/>
                    <RowDefinition Height="85"/>
                    <RowDefinition Height="5"/>
                </Grid.RowDefinitions>

                ......

                <!--菜單欄彈出區域-->
                <StackPanel x:Name="stkPnlShowFooter" Grid.Row="4" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="Transparent" MouseEnter="stkPnlShowFooter_MouseEnter">
                    <!--右下角擴展的區域：500*50-->
                    <StackPanel Width="500" Height="50" Margin="0,-50,0,0" Background="Transparent" HorizontalAlignment="Right"/>
                </StackPanel>
            </Grid>

        /// <summary>
        /// 隱藏菜單欄
        /// </summary>
        private void userCtrlFooter_MouseLeave(object sender, MouseEventArgs e)
        {
            SetFooterHidden();
        }

        /// <summary>
        /// 隱藏底部一級菜單欄
        /// </summary>
        public void SetFooterHidden()
        {
            contentPercentage = 0.84;

            if (this.layoutPopup != null)
                this.layoutPopup.Height = (int)(this.Height * contentPercentage);//重置Layout高度

            gridMain.RowDefinitions[3].SetValue(RowDefinition.HeightProperty, new System.Windows.GridLength(0, GridUnitType.Pixel));

            userCtrlFooter.SetValue(Grid.RowSpanProperty, 1);//底部菜單欄
            userCtrlFooter.Visibility = Visibility.Collapsed;//底部菜單欄
            mainContent.SetValue(Grid.RowSpanProperty, 2);//內容展示區
            mainContent.Visibility = Visibility.Collapsed;//內容展示區
            mainContent.Visibility = Visibility.Visible;//內容展示區
            stkPnlShowFooter.Visibility = Visibility.Visible;//高度爲5的底部彈出區域
        }

        /// <summary>
        /// 彈出菜單欄
        /// </summary>
        private void stkPnlShowFooter_MouseEnter(object sender, MouseEventArgs e)
        {
            contentPercentage = 0.76;

            if (this.layoutPopup != null)
                this.layoutPopup.Height = (int)(this.Height * contentPercentage);//重置Layout高度

            gridMain.RowDefinitions[3].SetValue(RowDefinition.HeightProperty, new System.Windows.GridLength(85, GridUnitType.Pixel));

            stkPnlShowFooter.Visibility = Visibility.Collapsed;//高度爲5的底部彈出區域
            userCtrlFooter.SetValue(Grid.RowSpanProperty, 2);//底部菜單欄
            userCtrlFooter.Visibility = Visibility.Visible;//底部菜單欄
            mainContent.SetValue(Grid.RowSpanProperty, 1);//內容展示區
            mainContent.Visibility = Visibility.Collapsed;//內容展示區
            mainContent.Visibility = Visibility.Visible;//內容展示區
        }