I have a similar problem but I was using SurfaceView properly as you mention Romain Guy but changing my code over does not work. The problem and code was posted here http://stackoverflow.com/questions/12688409/android-textureview-canvas-drawing-problems The unlockandpostcanvas method does nothing. neither does TextureView.invalidate or surface.updateTexImage(). Only tapping the screen gets it to display?? Any ideas?
On Monday, 1 October 2012 18:17:57 UTC+2, Romain Guy (Google) wrote: > > There is an overhead associated to invalidate() but unless your > hierarchy is extremely complicated it shouldn't be such an issue. But > you're right: SurfaceView can be used to avoid calling invalidate() > but don't override it's onDraw() method. You usually create a new > thread that renders onto the surface. > > On Mon, Oct 1, 2012 at 2:53 AM, Ajit Vasudevan > <[email protected]<javascript:>> > wrote: > > Hi Romain, > > > > Thanks for your response. > > > > I was experiencing a very interesting behavior. I started using a custom > > view inside a framelayout, and performed all the primitive operations > and > > called invalidate() to let the system call onDraw. It was choking. I > even > > tried to invalidate a rect, but it was just not fast enough - the 2nd > view > > that was requesting the underlying view to redraw certain primitives > based > > on the actions on the 2nd view was not responsive. I then started using > the > > SurfaceView to see if there is any benefit for the same operation - and > > voila - it worked like a charm. This is why is used SurfaceView as a > > substitute - there was an apparent performance benefit. > > > > That said, I'm going to take another look at my hierarchy, and all the > > custom views (there are quite a few), to make sure there are no other > leaks. > > Like you said, I would rather use a View instead of SurfaceView. Thanks > for > > your input though - it does answer the question that I can use a canvas > with > > TextureView if i follow the intended mode of use. > > > > -Ajit > > > > On Saturday, September 29, 2012 2:47:45 PM UTC-7, Romain Guy (Google) > wrote: > >> > >> Hi, > >> > >> If you were using SurfaceView's onDraw() method then you were not > >> getting any benefit. You have to use > >> lockCanvas()/unlockCanvasAndPost() and post on the underlying Surface. > >> TextureView works in a similar way: you can call > >> lockCanvas()/unlockCanvasAndPost(). > >> > >> However, it seems all you need is a View. It's easier to use and since > >> you are not using SurfaceView properly anyway it will do the same > >> thing. > >> > >> On Thu, Sep 27, 2012 at 2:19 PM, Ajit Vasudevan <[email protected]> > wrote: > >> > Hello, > >> > > >> > I am currently working on an app that requires computations/rendering > >> > based > >> > on a variety of user inputs. I have implemented the SurfaceView and > >> > things > >> > work as expected. > >> > But I started facing performance issues when I tried to put this > inside > >> > a > >> > horizontal scroll view. Obviously it is not intended to work this way > - > >> > but > >> > I tried anyway :) > >> > Based on what I have read - it appears like I have to move to > >> > TextureView. > >> > But i am unable to override the onDraw, and therefore cannot perform > the > >> > necessary drawing using the Canvas. This might be a trivial question > - > >> > but I > >> > wanted to know if we can use TextureView to draw primitives on the > >> > screen > >> > using a Canvas? The only examples I have seen thus far show the use > of > >> > video/camera/openGL rendering on the TextureView. > >> > > >> > Any help on this would be great. > >> > > >> > Thanks much > >> > -Ajit > >> > > >> > -- > >> > You received this message because you are subscribed to the Google > >> > Groups "Android Developers" group. > >> > To post to this group, send email to [email protected] > >> > To unsubscribe from this group, send email to > >> > [email protected] <javascript:> > >> > For more options, visit this group at > >> > http://groups.google.com/group/android-developers?hl=en > >> > >> > >> > >> -- > >> Romain Guy > >> Android framework engineer > >> [email protected] > > > > -- > > You received this message because you are subscribed to the Google > > Groups "Android Developers" group. > > To post to this group, send email to > > [email protected]<javascript:> > > To unsubscribe from this group, send email to > > [email protected] <javascript:> > > For more options, visit this group at > > http://groups.google.com/group/android-developers?hl=en > > > > -- > Romain Guy > Android framework engineer > [email protected] <javascript:> > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
