moving ball

[bharat]

hi everyone..i am new to iphone development..
can any one plz tell me how to start and stop a ball with start and stop button respectively...

[bharat]

can anyone plzz help..

[Slade]

Are you starting from scratch? Is the ball you want to move displayed on your screen? If so please show us some of your code, it will be easier to help you then :-)

[bharat]

yes starting from fresh...i want to move a ball by pressing the button...


-(void) onTimer{
ball.center = CGPointMake(ball.center.x+pos.x,ball.center.y+pos. y);
if(ball.center.x > 320 || ball.center.x < 0)
pos.x = -pos.x;
if(ball.center.y > 460 || ball.center.y < 0)
pos.y = -pos.y;

}

- (void)viewDidLoad
{
pos=CGPointMake(14.0, 7.0);

}
now i want that when the stimulator opens the ball remains still and after pressing the start button it should move and then stop after pressing stop..
may be i have to do something inside
- (IBAction)buttonPressedid)sender..
no idea..

[Justinmichael]

Originally Posted by bharat

yes starting from fresh...i want to move a ball by pressing the button...


-(void) onTimer{
ball.center = CGPointMake(ball.center.x+pos.x,ball.center.y+pos. y);
if(ball.center.x > 320 || ball.center.x < 0)
pos.x = -pos.x;
if(ball.center.y > 460 || ball.center.y < 0)
pos.y = -pos.y;*/

}

- (void)viewDidLoad
{
pos=CGPointMake(14.0, 7.0);

}
now i want that when the stimulator opens the ball remains still and after pressing the start button it should move and then stop after pressing stop..
may be i have to do something inside
- (IBAction)buttonPressedid)sender..
no idea..

Change your time code to - a variable from the pos.x and change the value of the variable on your buttonPressed method:

int moveX = 0;
int moveY = 0;

-(void) onTimer{
    ball.center = CGPointMake(ball.center.x+moveX,ball.center.y+moveY);  
/*
    if(ball.center.x > 320 || ball.center.x < 0)
        pos.x = -pos.x;
    if(ball.center.y > 460 || ball.center.y < 0)
        pos.y = -pos.y;
*/
    
}

/*
- (void)viewDidLoad
{
    pos=CGPointMake(14.0, 7.0);
    
}*/

- (IBAction)buttonPressed:(id)sender {
    if (moveX > 0) {
        moveX = 0;
    } else {
        moveX = 1;
    }
}

[Slade]

Don´t worry, I´m sure we´ll be able to make the ball move :-). If you want the ball to start and stop after pushing the buttons I would introduce a new variable: speed. When you press the stop button the speed should be set to zero. And the start button should set the speed to 1. But then you need to change your code a little. For example:

if(ball.center.x < 320 || ball.center.x > 0)
ball.center.x = ball.center.x + speed;
if(ball.center.y < 480 || ball.center.y > 0)
ball.center.y = ball.center.y + speed;

I corrected the code a litte, it should check that the ball is inside the screens boundaries :-). Also, you should change the direction of the ball once it hits the walls but we can save that for later. Try it out and see it you can get the ball moving.

[bharat]

Originally Posted by Justinmichael

Change your time code to - a variable from the pos.x and change the value of the variable on your buttonPressed method:

int moveX = 0;
int moveY = 0;

-(void) onTimer{
    ball.center = CGPointMake(ball.center.x+moveX,ball.center.y+moveY);  
/*
    if(ball.center.x > 320 || ball.center.x < 0)
        pos.x = -pos.x;
    if(ball.center.y > 460 || ball.center.y < 0)
        pos.y = -pos.y;
*/
    
}

/*
- (void)viewDidLoad
{
    pos=CGPointMake(14.0, 7.0);
    
}*/

- (IBAction)buttonPressed:(id)sender {
    if (moveX > 0) {
        moveX = 0;
    } else {
        moveX = 1;
    }
}

hey thnks a lot for your help....bt still nt able to do...
when the build runs the ball is still but when i press the start or stop button its not moving...how to move ie..how to link the ball movement with those two button?????

[bharat]

Originally Posted by Slade

Don´t worry, I´m sure we´ll be able to make the ball move :-). If you want the ball to start and stop after pushing the buttons I would introduce a new variable: speed. When you press the stop button the speed should be set to zero. And the start button should set the speed to 1. But then you need to change your code a little. For example:

if(ball.center.x < 320 || ball.center.x > 0)
ball.center.x = ball.center.x + speed;
if(ball.center.y < 480 || ball.center.y > 0)
ball.center.y = ball.center.y + speed;

I corrected the code a litte, it should check that the ball is inside the screens boundaries :-). Also, you should change the direction of the ball once it hits the walls but we can save that for later. Try it out and see it you can get the ball moving.

thnx for your help..bt am not able to get it done...

[new2objectivec]

try this: Making a simple iPhone game, part 1 - YouTube

ball bouncing game tutorial with full video