Grouping elements in loop using React Native

Question

I'm listing events with their start date+time. This works well, but I want to group the event by their dates as events happen on the same day. I want to do this by assigning an extra <View> above the group with the event date.

My code currently looks like this:

renderEvents() {
   
   return this.state.data.map((post, index) => {
       return (
           <View key={post.id}>
           <Text>{post.start_dateTime}</Text>  
           <Text>{post.title}</Text>
           </View>  
       );
   });
 }

However, I cannot do an if/else statement in this return()

If I make a function to save the current handling date and loop further until a next date is found using setState, it gives me an "Error: Too many re-renders. React limits the number of renders to prevent an infinite loop."

What could be the best way to approach this issue?