How many ViewGroup (LinearLayout, Relative, Grid,

问题:

I tried to find an answer for this specific question but I couldn't. I watched a video https://www.youtube.com/watch?v=NYtB6mlu7vA and I got the impression that over using Layouts generally is expensive. Apps like twitter, use complex designs that consists of many nested group views

I realize that these are rows inside a listview, and they are recycled, but my question is, is this considered bad practice generally?

The video they discussed the fact that linearlayout performs a calculation to draw elements inside it, and it gets worse when you nest multiple linearlayouts.

回答1:

According to Lint Checks:

Layout has too many views

The maximum view count defaults to 80 but can be configured with the environment variable ANDROID_LINT_MAX_VIEW_COUNT.

Layout hierarchy is too deep

Layouts with too much nesting is bad for performance. Consider using a flatter layout (such as RelativeLayout or GridLayout).The default maximum depth is 10 but can be configured with the environment variable ANDROID_LINT_MAX_DEPTH.

According to my experience:

If your app supports api 9+ I recommend having less than 12 nested views. Usually these devices have limitations on memory. You can get OutOfMemoryException or StackOverflowException. StackOverflow happens when "Composite" pattern recursively walks through hierarchy.