Learned yesterday, the method of collision judgment, and learn the new usage of nstimer, today I practice doing a game of bricks, the game realized from the left and right on the three walls, there are 15 bricks, a small ball, a baffle, through the small ball hit the wall and the baffle to achieve the ball. But do not realize after the disappearance of the bricks, can only do a good job of the last created bricks have disappeared after the effect of the crash, this afternoon to review some of the knowledge learned
Property @property attribute Concept OC language has, C language does not, Self calls the method of the current object, and the object method is tuned with the object name of the instance . The access property in the class is a point, and the access method is with a space. basic data types, such as int,float,double, are stored in the stack memory when they declare negative values. Global variables are not initialized by default is 0 and nil, local variables are not initialized by default is a random class method can not declare only implementation, but can not only declare, if the free declaration will be an error, understand that there is a person said that they can do something, But he can't do it specifically. If a method is only implemented then it is private and can only be called by itself, and this method only knows for itself. If introduced in another. m file, it cannot be used because his own method is not declared. Not known in other documents.
Lan Yi iOS Practice Games 2