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 <[email protected]> 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<[email protected]> 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 [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 -~----------~----~----~----~------~----~------~--~---
