How to change a sub-activity to a top level activity

You can easily turn a sub-activity to a top level activity.

Method 1 (drag-n-drop):

1. Open Activity Center.
2. Make sure that the Flat View is disabled under the Show button.
3. Locate the activity you want to turn into a top-level activity.
4. Drag the activity onto the project row until the latter gets surrounded with a thick black rectangular frame.
5. Let go of the activity being moved.

Method 2:

1. Open Activity Center.
2. Hover on the activity you want to turn into a sub-activity of another activity and click Details.
3. In Activity details section, hover the pointer over the hierarchy of the activity until '— change' appears.
4. Click '— change'.
5. Click "Set as top-level activity".