When you converted list_item_crime.xml to use ConstraintLayout, Android Studio automatically added the constraints it thinks will replicate the behavior of your old layout. However, to learn how constraints work you are going to start from scratch.
Select the top-level view in the component tree, labeled linearLayout. Why does it say linearLayout, when you converted it to a ConstraintLayout? That is the ID the ConstraintLayout converter supplied. linearLayout is, in fact, your ConstraintLayout. You can check the XML version of your layout if you want to confirm this.
With linearLayout selected in the component tree, click the Clear All Constraints button (shown in Figure 10.8). You will immediately see red ...