how to create gearjoint in andengine
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I'm using AndEngine for my android game, and I want to create GearJoint with the method physicsworld.createJoint(mGearJoint); But when I run the project and I got the ANR problem,I think there is something wrong with the method.? I'm not sure. who can I solve the problem? thanks.
here are my codes

    GearJointDef gjointdef=new GearJointDef();
			
			RevoluteJointDef rjointdef=new RevoluteJointDef();
			rjointdef.initialize(gear10, ground, ground.getWorldCenter());
			rjointdef.enableMotor=true;
			rjointdef.motorSpeed=0;
			rjointdef.maxMotorTorque=20;
			Joint rjoint=world.createJoint(rjointdef);
			
			PrismaticJointDef pjointdef=new PrismaticJointDef();
			pjointdef.initialize(gear11, ground, ground.getWorldCenter(), new Vector2(1.0f, 0.0f));
			pjointdef.lowerTranslation=-5;
			pjointdef.upperTranslation=2.5f;
			pjointdef.enableLimit=true;
			pjointdef.motorSpeed=0;
			pjointdef.enableMotor=true;
			Joint pjoint=world.createJoint(pjointdef);
			
			gjointdef.bodyA=gear10;
			gjointdef.bodyB=gear11;
			gjointdef.joint1=rjoint;
			gjointdef.joint2=pjoint;
			gjointdef.ratio=(float) (2f*Math.PI/40);
			
			world.createJoint(gjointdef);

 