Ok, i see.... I think coming from flash I think to much in timelines and frames. In Java there is offcourse no such thing, so i understand ( i think ) why one needs to sometimes revert back to previous canvas state.
Thnx for clearing that up. Jiri Streets Of Boston wrote: > Before you call save() on the canvas, your canvas is in a certain > state (clip region/transformation matrix/etc). > Then you call save() and all this info is saved away somewhere. > > Then other code (e.g. paints of child-views) can modify this canvas > anyway they like. > > Then when control is returned back to your code, just call restore > (level) on the canvas to get your old saved state back. > > // do some drawing/clipping/scaling/etc on my canvas > ... > ... > int level = canvas.save(); > letSomeOtherCodeDoSomeDrawing(canvas); > // after this, the canvas could be in any (unknown) state > > // restore to my known state, as it was just before > // calling letSomeOtherCodeDoSomeDrawing > canvas.restoreToCount(level); > > // do some more drawing/clipping/scaling etc on the canvas > ... > > > On Aug 14, 10:55 am, Jiri <jiriheitla...@googlemail.com> wrote: >> Thanks Jeff, >> >> not sure if i understand it correctly. I come from an AS3 background and >> tf matrixes i understand. >> So if i would scale the canvas via a matrix and then draw stuff on it, >> this stuff is then scaled when drawn. >> if i then after the scaling do a restore() all is 100% scaled again? >> >> Or is that the matrix is resetted but the drawn stuff remains how it was >> before calling the restore()? >> >> jiri >> >> >> >> Jeff Sharkey wrote: >>> Think of it as checkpointing the transformation matrix and clip >>> rectangle of your Canvas at a known place in time. This is useful >>> when rendering children views that may leave them in an unknown state. >>> (You can restore back to the checkpointed state when children are >>> done drawing.) Here's an example from ViewGroup: >>> final int restoreTo = canvas.save(); >>> [perform some drawing that might change the transformation matrix or >>> clip rectangle] >>> canvas.restoreToCount(restoreTo); >>> j >>> On Thu, Aug 13, 2009 at 3:04 AM, Jiri<jiriheitla...@googlemail.com> wrote: >>>> Could someone explain to me the canvas.save() and restore(). I come from >>>> a flash background, and this is a new concept for me. Reading the >>>> documentation is not helpfull. >>>> Jiri- Hide quoted text - >> - Show quoted text - > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@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 -~----------~----~----~----~------~----~------~--~---
