As it happens our friend Romain Guy did have some ideas https://groups.google.com/forum/?fromgroups=#!topic/android-developers/_Ogjc8sozpA
thank you On Wednesday, 3 October 2012 11:34:58 UTC+2, Conrad Chapman wrote: > > 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 <vasu...@gmail.com> >> 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 <vasu...@gmail.com> >> 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 android-d...@googlegroups.com >> >> > To unsubscribe from this group, send email to >> >> > android-developers+unsubscr...@googlegroups.com >> >> > For more options, visit this group at >> >> > http://groups.google.com/group/android-developers?hl=en >> >> >> >> >> >> >> >> -- >> >> Romain Guy >> >> Android framework engineer >> >> roma...@android.com >> > >> > -- >> > You received this message because you are subscribed to the Google >> > Groups "Android Developers" group. >> > To post to this group, send email to android-d...@googlegroups.com >> > To unsubscribe from this group, send email to >> > android-developers+unsubscr...@googlegroups.com >> > For more options, visit this group at >> > http://groups.google.com/group/android-developers?hl=en >> >> >> >> -- >> Romain Guy >> Android framework engineer >> roma...@android.com >> > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. 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