Simple TextView.setText causes 40% CPU Usage

I noticed this myself a while ago, I think the problem is that every time you call setText, the size of the textbox can change, thus requiring the entire screen to go through relayout (expensive).

I haven't tried this myself yet, but if your textbox is simple and can be made to be a relatively fixed size, maybe try to subclass TextView and create a view that does not resize itself on setText, but rather just draws whatever it can into the existing area? That would save a lot of time.

Perhaps theres already a flag to setText that can make it do this, but I'm not aware of it, though I haven't searched closely.

In my case, I update a TextView from touch event, which cause a lot of updating The solution was to change the TextView layout_width & layout_height to fixed sized.

some possible improvements :

1. try using a handler which updates the textview every 0.5 seconds instead of a thread that does it.
2. make the runnable a final constant object instead of craeting a new one every second.
3. consider checking that the time has changed (newTimeInMs-LastPublishedTimeInMs>=1000) before telling the textview to update itself.
4. instead of String.format , try using StringBuilder . however , you won't enjoy the locale solution that the String.format gives (for example , for arabic digits) .