Debugging the UI

We have focused until now on memory, threading, and the system aspects of Android. There is a more visual aspect that can also dramatically improve the performance of our application: the user interface (UI). Android provides a tool called Hierarchy Viewer to debug and optimize any UI designed for Android. Hierarchy Viewer provides a visual representation of the hierarchy of layouts of an application with information about the performance of each node that can be found on the layout. It provides a so-called Pixel Perfect window with magnified information of the display, in case a close look at pixels is required.

To run Hierarchy Viewer, we need first to connect our device or emulator. Note that, for security reasons, only devices running a developer version of the Android system will work with Hierarchy Viewer. When it has been connected, launch the hierarchyviewer program from the /tools directory. If you have not yet set up this directory as part of your system PATH, this...