The reason for NPE is that callback is registered too early, so one callback is invoked before controller is fully inited. This cl fix it in two ways: 1. Add NPE check in refreshUi, since this method in InstalledAppDetail is robost to NPE 2. Move the callback to the end of constructor. Bug: 37913054 Test: RunSettingsRoboTests Change-Id: I54b03fb51a958a8e63bfe8a7ccfda79be1fa1956