删除和更改ListView ViewCells中的项目

Question

In a project I am coding I am trying to make it so if a user clicks an options Icon it opens a menu where the user has the option to delete the post and it removes it from the List, I also want to make it so if users click the like button it changed the icon.

My problem is, I can't find out how to get a variable attached to that ViewCell so in the method I can delete it or update the like button.

My ListView is

<ListView x:Name="MessageView" HasUnevenRows="True" IsPullToRefreshEnabled="True" Refreshing="MessageView_Refreshing">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <ViewCell>
                        <StackLayout x:Name="MessageLayout" BackgroundColor="White" Margin="10, 10, 10, 0" Padding="10, 10, 15, 10">
                            <Image Source="options_icon.png" HeightRequest="15" HorizontalOptions="End" Margin="0, 0, 10, 0">
                                <Image.GestureRecognizers>
                                    <TapGestureRecognizer Command="{Binding OptionClick}"/>
                                </Image.GestureRecognizers>
                            </Image>
                            <Label Text="{Binding Body}" HorizontalOptions="CenterAndExpand" TextColor="Black" FontSize="15" Margin="0, 10, 0, 10"/>
                            <StackLayout x:Name="MessageFooter" Orientation="Horizontal">
                                <Image x:Name="LikeSource" Source="{Binding LikeImageSource}" HeightRequest="18" HorizontalOptions="StartAndExpand" Margin="0, 0, 10, 0">
                                    <Image.GestureRecognizers>
                                        <TapGestureRecognizer Command="{Binding LikeClick}" CommandParameter="{Binding .}"/>
                                    </Image.GestureRecognizers>
                                </Image>
                                <Label Text="{Binding Timestamp}" TextColor="Black" FontSize="10" HorizontalOptions="EndAndExpand"/>
                            </StackLayout>
                        </StackLayout>
                    </ViewCell>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>

Then the code behind it

        public IList<MessageObject> FormatPosts(Page page, INavigation navigation, string json)
    {
        IList<MessageObject> Posts = new List<MessageObject>() { };
        var messages = JsonConvert.DeserializeObject<List<Message>>(json);

        foreach (var message in messages)
        {
            DateTime dateFormat = Convert.ToDateTime(message.TimeStamp);
            Posts.Add(new MessageObject
            {
                Body = message.Body,
                OptionClick = new Command(() => ShowOptionActions(page, navigation, message.Id, message.Sender_Id)),
                ImageSource = message.Liked == 0 ? "like_icon.png" : "liked_icon.png",
                LikeClick = new Command(async (sender) => await LikeMessage(navigation, message.Sender_Id, sender)),,
                Timestamp = dateFormat.ToString("MMMM dd, yyyy HH:mm")
            });
        }

        return Posts;
    }

    public static async void ShowOptionActions(Page page, INavigation navigation, int id, int poster_id)
    {
        var action = await page.DisplayActionSheet("Message Actions", "Cancel", "Delete");
        switch (action)
        {
            case "Delete":
                await DeleteMessage(page, navigation, id);
                break;
        }
    }

    public static async Task LikeMessage(INavigation navigation, int id, object message)
    {
  *Updates database*
if (page_result.Equals("liked"))
        {
            ((MessageObject)message).LikeImageSource = "liked_icon.png";
        }
        else if (page_result.Equals("unliked"))
        {
            ((MessageObject)message).LikeImageSource = "like_icon.png"; // same as when you haven't liked it yet
        }
}

    public static async Task DeleteMessage(Page page, INavigation navigation, int id)
    {
        *Deletes from database*
        //Delete post
            return;

    }

}

public class MessageObject
{
    public string Body { get; set; }
    public Command OptionClick { get; set; }
    public Command LikeClick { get; set; }
    public string Timestamp { get; set; }
    public string ImageSource { get; set; }
}

Answer 1

这会将选定的MessageObject作为参数传递给OptionClick命令

<TapGestureRecognizer Command="{Binding OptionClick}" CommandParameter="{Binding .}"/>