MAUI导航栏-Android

底部导航栏-TabBar，示例：

<?xml version="1.0" encoding="UTF-8" ?>
<Shell
    x:Class="Test.AppShell"
    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
    xmlns:local="clr-namespace:Test"
    Shell.FlyoutBehavior="Disabled">
    <TabBar>
        <ShellContent
            Title="笔记"
            ContentTemplate="{DataTemplate local:MyPage.Views.NotePage}"
            Icon="icon_notes" />
        <ShellContent
            Title="关于"
            ContentTemplate="{DataTemplate local:MyPage.Views.AboutPage}"
            Icon="icon_about" />
    </TabBar>
</Shell>

顶部导航栏-ContentPage.ToolbarItems，示例：

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:models="clr-namespace:Test.MyPage.Models"
             x:Class="Test.MyPage.Views.AllNotesPage"
             Title="笔记列表">
    <ContentPage.ToolbarItems>
        <ToolbarItem Text="Add" Clicked="Add_Clicked" IconImageSource="{FontImage Glyph='+', Color=White, Size=22}" />
    </ContentPage.ToolbarItems>
    <!-- 在列表中显示注释 -->
    <CollectionView x:Name="notesCollection"
                        ItemsSource="{Binding Notes}"
                        Margin="20"
                        SelectionMode="Single"
                        SelectionChanged="notesCollection_SelectionChanged">

        <!-- 指定项目集合的布局方式 -->
        <CollectionView.ItemsLayout>
            <LinearItemsLayout Orientation="Vertical" ItemSpacing="10" />
        </CollectionView.ItemsLayout>

        <!-- 定义列表中每个项目的外观 -->
        <CollectionView.ItemTemplate>
            <DataTemplate>
                <StackLayout>
                    <Label Text="{Binding Text}" FontSize="22"/>
                    <Label Text="{Binding Date}" FontSize="14" TextColor="Silver"/>
                </StackLayout>
            </DataTemplate>
        </CollectionView.ItemTemplate>
    </CollectionView>
</ContentPage>