Checking and unchecking an item

To check and uncheck an item is simple. For this, we would need to make a PATCH or PUT HTTP request. If we were just sending a single attribute to update, we would make a PATCH request. If we are passing all of the attributes then we would make a PUT request. The difference is that in the PUT request, any attributes that are not passed are saved as NULL in the database. In PATCH requests, only the attributes that are passed are updated, and the ones that are not passed remain unchanged. In our case, since we already have a computed property called data, which contains all of the attributes of an item object in JSON format, we can make either a PUT or PATCH request. To make checking and unchecking work, we would need to first invert the value of isChecked and then make a PUT request to the server by passing the JSON representation of the item object in the body of the request. Then we would need to parse the response and convert the JSON back to an item and...