Android :: Any Way To Speed Up Drawing To Make Animation Smooth?

I am creating an app that show some histograms off your traveling speed in different time periods (histogram for the last minute, histogram for the last 2 minutes etc.) I would like to have an animation, and have discovered that drawing everything takes around 300-400ms. Which is to long for making my animation smooth, the animation itself is quite simple (2 lines and 2 dots). What I draw every frame right now is 20 antialised strings, size 14, in average ~5chars 8 of these strings will change every second. 1 of the string will change with the animation (this will become 5 strings if there is time).

The main part of the screen, the one showing the histogram data, consist of a lots of squares which needs to be updated every second. (450 squares). The presentation is split into 5 frames in the same view (has to be same view as arrows in one frame might point into another frame). Invalidating only a part off the screen makes almost no difference (it does becomes a bit faster, but i still execute all my drawing stuff). I have tried to add a flag whether or not the main part is dirty, but if I don't draw it, it is cleared. I might be missing something here. One possibility could be to render all the mostly static stuff to a bitmap, and then simply draw the bitmap. That would mean 10 strings only had to rendered on orientation change.

I think it would make sense since the slowest routine is the one drawing all the text. (the following is a typical timing for the drawing routines, accumulated).
V/HMMULTIBAR( 352): 0 - Drawing time: 0 ms V/HMMULTIBAR( 352): 1 - Drawing time: 53 ms V/HMMULTIBAR( 352): 2 - Drawing time: 62 ms V/HMMULTIBAR( 352): 3 - Drawing time: 85 ms V/HMMULTIBAR( 352): 4 - Drawing time: 280 ms V/HMMULTIBAR( 352): 5 - Drawing time: 303 ms
I would really appreciate comments about whether or not offscreen rendering is the way to go, or if there is a simpler way.