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我是否需要执行任何特定的操作,以使主工具栏项在Android上显示为禁用状态_Android_Xaml_Xamarin.forms - Fatal编程技术网

我是否需要执行任何特定的操作,以使主工具栏项在Android上显示为禁用状态

我是否需要执行任何特定的操作,以使主工具栏项在Android上显示为禁用状态,android,xaml,xamarin.forms,Android,Xaml,Xamarin.forms,我有以下XAML <ContentPage.ToolbarItems> <ToolbarItem x:Name="tbiEdit" Text="Edit" Order="Primary" Priority="1" Command="{Binding ToggleEditCommand}"> <ToolbarItem.Icon> <OnPlatform x:TypeArguments="FileImageSo

我有以下XAML

<ContentPage.ToolbarItems>
    <ToolbarItem x:Name="tbiEdit" Text="Edit" Order="Primary" Priority="1" Command="{Binding ToggleEditCommand}">
        <ToolbarItem.Icon>
            <OnPlatform x:TypeArguments="FileImageSource">
                <On Platform="Android" Value="ic_edit_white_24dp.png"/>
                <On Platform="UWP" Value="Assets/Icons/ic_edit_dark_48dp.png"/>
            </OnPlatform>
        </ToolbarItem.Icon>
    </ToolbarItem>
    <ToolbarItem x:Name="tbiSave" Text="Save" Order="Primary" Priority="2" Command="{Binding SaveOrderCommand}">
        <ToolbarItem.Icon>
            <OnPlatform x:TypeArguments="FileImageSource">
                <On Platform="Android" Value="ic_save_white_24dp.png"/>
                <On Platform="UWP" Value="Assets/Icons/ic_save_dark_48dp.png"/>
            </OnPlatform>
        </ToolbarItem.Icon>
    </ToolbarItem>
    <ToolbarItem x:Name="tbiCopy" Text="Copy" Order="Secondary" Priority="3" Command="{Binding CopyOrderCommand}">
        <ToolbarItem.Icon>
            <OnPlatform x:TypeArguments="FileImageSource">
                <On Platform="Android" Value="ic_content_copy_white_24dp.png"/>
                <On Platform="UWP" Value="Assets/Icons/ic_content_copy_dark_48dp.png"/>
            </OnPlatform>
        </ToolbarItem.Icon>
    </ToolbarItem>
    <ToolbarItem x:Name="tbiDelete" Text="Delete" Order="Secondary" Priority="4" Command="{Binding DeleteOrderCommand}">
        <ToolbarItem.Icon>
            <OnPlatform x:TypeArguments="FileImageSource">
                <On Platform="Android" Value="ic_delete_white_24dp.png"/>
                <On Platform="UWP" Value="Assets/Icons/ic_delete_dark_48dp.png"/>
            </OnPlatform>
        </ToolbarItem.Icon>
    </ToolbarItem>
</ContentPage.ToolbarItems>

你能发布你的命令码吗?@Billy,已经用检查逻辑更新了帖子。我希望这就是你想要的代码。@Lindsay我想知道你是否还有这个问题?@Matthewregl,很遗憾,是的,我有。这听起来像是个bug。我建议您在Xamarin.Forms repo上提交一个问题。请确保您尝试使用最新的Xamarin.Forms版本,以确保它不是已经解决的问题。
private bool CanSave()
    {
        if (!IsVMInEditMode) return false;
        if (!DisplaySaveWarning) return false;
        if (string.IsNullOrWhiteSpace(Title)) return false;
        if (string.IsNullOrWhiteSpace(Details)) return false;
        if (Title.Length > 50) return false;
        if (Details.Length > 1000) return false;
        return true;
    }

private bool CanToggleEdit()
    {
        if (_order == null) return false;
        if (!_order.IsUserCreated) return false;
        return true;
    }