Hi I'm from Brazil and I'm developing a Beat'em Up game for my conclusion work in universisty. I'm using a game api in this site trunk - sporksoft - Project Hosting on Google Code This game api is exactly the same as the jme. I'm having a problem, each time I use a game api method I have an null error and my app stop. Code (Text): //Method that adjusts Axel's sprite public void adjustAxel( Sprite s, double mx, double my ){ try{ mPositionX = (int) mX; mPositionY = (int) mY; mManager.append( mAxelSprite ); mAxelSprite.defineReferencePixel( mAxelWidth / 2, 0 ); mAxelSprite.setRefPixelPosition ( mPositionX, mPositionY); mAxelSprite.setFrameSequence( mFrameSequence ); }catch( Exception e ){ Log.e( CATEGORIA, "Error 2: " + e.getMessage() ); } } I don't have an idea how to fix it, and in my country are very few people that develop in android platform so here I'm to search for help. Greetings John Peter