Câu trả lời How to render different types of ViewCe...
To render different types of ViewCell in the same ListView during runtime in Xamarin.Forms, you can use the DataTemplateSelector class. This approach allows you to dynamically choose a DataTemplate based on the data being bound to the ListView. Here’s a step-by-step guide on how to achieve this:
Step 1: Create DataTemplates
First, define the different DataTemplate instances that you want to use. Each DataTemplate will represent a different type of ViewCell.
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public class IncomingViewCell : ViewCell
{
public IncomingViewCell()
{
var label = new Label { Text = "Incoming Message" };
View = new StackLayout
{
Children = { label }
};
}
}
public class OutgoingViewCell : ViewCell
{
public OutgoingViewCell()
{
var label = new Label { Text = "Outgoing Message" };
View = new StackLayout
{
Children = { label }
};
}
}
Step 2: Create a DataTemplateSelector
Next, create a class that inherits from DataTemplateSelector and override the OnSelectTemplate method. This method will contain the logic to select the appropriate DataTemplate based on the data.
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public class MessageDataTemplateSelector : DataTemplateSelector
{
private readonly DataTemplate incomingTemplate;
private readonly DataTemplate outgoingTemplate;
public MessageDataTemplateSelector()
{
incomingTemplate = new DataTemplate(typeof(IncomingViewCell));
outgoingTemplate = new DataTemplate(typeof(OutgoingViewCell));
}
protected override DataTemplate OnSelectTemplate(object item, BindableObject container)
{
var message = item as MessageViewModel;
if (message == null)
return null;
return message.IsIncoming ? incomingTemplate : outgoingTemplate;
}
}
Step 3: Bind the DataTemplateSelector to the ListView
Finally, set the ItemTemplate property of the `Li...
