How to add multiple UIImageViews with same property - iphone

Question

I want to have multiple images (in this case, basketballs) move around on the screen.
How can I create multiple balls with the same name? I have one ball which is already moving around. So all the other balls should use the same calculation with the same property name for bumping and stuff like that.
Can someone help me? I know Java well, but not Obj C.
EDIT:
ball.center = CGPointMake(ball.center.x + ballmovement.x, ball.center.y + ball movement.y);
if (ball.center.x > self.view.frame.size.width || ball.center.x < 0) {
ballmovement.x = -1* ballmovement.x;
}
if (ball.center.y > self.view.frame.size.height || ball.center.y < 0) {
ballmovement.y = -1* ballmovement.y;
This is my simple calculation. This code is in my loop method. this loop method is called by this code in my viewDidLoad method:
[NSTimer scheduledTimerWithTimeInterval:0.050 target:self selector:#selector(loop) userInfo:nil repeats:YES];
In the MainView .h file i wrote
BasketballView *ball;
new Balls are created by this code in my button action method:
for (int x = 0; x < numberOfBalls; x++)
{
ball = [[BasketballView alloc]initWithFrame:CGRectMake(arc4random()%100,arc4random()%100, 40, 40) andCustomProperty:#"my string" andAnotherProperty:100];
[self.view addSubview:ball];
}
When i run my application, only one ball is moving!
do you need more code?
thanks for your help
EDIT 2:
every ball is moving now, but they are not moving correctly .. here is what i did. i created a NSMuteableArray. i added this code in my Button action method:
[array addObject:ball];
after that, i added in the loop method some code. here is the new loop code that i have right now:
for (int i=0; i<array.count;i++){
ball = [array objectAtIndex:i];
ball.center = CGPointMake(ball.center.x + ballmovement.x, ball.center.y + ballmovement.y);
}
if (ball.center.x > self.view.frame.size.width || ball.center.x < 0) {
ballmovement.x = -1* ballmovement.x;
}
if (ball.center.y > self.view.frame.size.height || ball.center.y < 0) {
ballmovement.y = -1* ballmovement.y;
right now, every ball is changing direction when one ball hits the boarder. so all the other balls move like the this one ball. they ignore the boarders. only if this one ball hits the boarder, they change their direction.
if i put the code for the ball movement inside the for-loop, the balls change their direction everytime one of the balls hits the boarder. they are moving like crazy, because every .5 seconds a ball hits one of the boarders

Answer 1

I think what you looking for is a way to add a bunch of objects from the same class. To do this, I would suggest that you overwrite an UIImageView class. If you do that, you can add custom properties to the balls. See the example below:
In your header file, you would have the following:
#import <UIKit/UIKit.h>
#interface BasketBallView : UIImageView
#property (nonatomic, strong) NSString *customProperty;
#property (assign) NSInteger anotherProperty;
//custom init method if you want
- (id) initWithFrame:(CGRect)frame andCustomProperty:(NSString *)CustomProperty andAnotherProperty:(NSInteger)AnotherProperty;
-(void)startMovement;
#end
The implementation would be something like this:
#import "BasketBallView.h"
#implementation BasketBallView
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self setImage:[UIImage imageNamed:#"your_bb_image.png"]];
}
return self;
}
-(id) initWithFrame:(CGRect)frame andCustomProperty:(NSString *)CustomProperty andAnotherProperty:(NSInteger)AnotherProperty
{
self = [self initWithFrame:frame];
if (self) {
self.customProperty = CustomProperty;
self.anotherProperty = AnotherProperty;
}
return self;
}
-(void)startMovement{
[NSTimer scheduledTimerWithTimeInterval:0.050 target:self selector:#selector(loop) userInfo:nil repeats:YES];
}
-(void)moveBall{
self.center = CGPointMake(self.center.x + ballmovement.x, self.center.y + ballmovement.y);
if (self.center.x > self.superview.frame.size.width || self.center.x < 0) {
ballmovement.x = -1* ballmovement.x;
}
if (self.center.y > self.superview.frame.size.height || self.center.y < 0) {
ballmovement.y = -1* ballmovement.y;
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect
{
// Drawing code
}
*/
#end
To then use and access your object from your viewcontroller, do it as follows:
BasketBallView *bb = [[BasketBallView alloc]initWithFrame:CGRectMake(0, 0, 100, 100) andCustomProperty:#"my string" andAnotherProperty:100];
[self.view addSubview:bb];
You could, of course, throw the above lines of code into a loop, and add it multiple times to the view.
Edit:
If you want to add the BasketBallView to the view for the Interface Builder, you'll need to customize the initWithCoder method in the implementation file. In that method, you would similarly set your image, etc.
I would suggest that you don't add the BasketBallViews via the Interface Builder, however. Since you need a random number of balls, you need to add them from the code and use the method I outlined above. You would add them like this:
for(int i = 0; i < yourRandomNumber; i++){
BasketBallView *bb = [[BasketBallView alloc]initWithFrame:CGRectMake(0, 0, 100, 100) andCustomProperty:#"my string" andAnotherProperty:100];
[self.view addSubview:bb];
}
You can't add copies of views to another view, in other words, you can't create the ball in the IB, then make copies of it in the code and add it to your view.
The properties I added to the class are just examples of some customization that you could add to the class if you needed to.
You can certainly still use the center property since the BasketBallView is an subclass of the UIImageView, and therefore inherits all the UIImageView properties.

Answer 2

If you have access to iOS7, or can wait another month, Apple's new SpriteKit framework will be able to do a lot of the physics and GPU rendering for you. Then it's just a case of making multiple instances of your "Basketball Class".

Answer 3

You need to add the uiimageview several times on the screen.... and set tag with number 100 or 1001
like
balview.tag = 100;
for (int x=0; x < 5; x++)
{
[self.view addSubview:ballView];
}
do calculation for all in one time
forin(UIImageView *view in [self.view subviews])
{
if (view.tag == 100)
{
//do something
}
}
for (int x = 0; x < 5; x++)
{
UIImageView* ball = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"YourImageName"]];
ball.frame = CGRectMake(20, 20*x, 20, 20);
[self.view addSubview:ball];
}

Answer 4

I can think of two solutions:
1: Add all balls to an array and access them by the index (seems more feasible to me)
2: Add them tags and access them by
[self.view viewWithTag:<BallTag>];
Edit: Seems like you have chosen the first alternative. Now you need to improve your method for only one ball to move and invoke it whenever you desire.
- (void)moveBallWithIndex:(int)idx{
//for (int i=0; i<array.count;i++){
//Loop removed. It was the reason why all the balls were moving
BasketballView * ball = [array objectAtIndex:idx];
ball.center = CGPointMake(ball.center.x + ballmovement.x, ball.center.y + ballmovement.y);
if (ball.center.x > self.view.frame.size.width || ball.center.x < 0) {
ballmovement.x = -1* ballmovement.x;
}
if (ball.center.y > self.view.frame.size.height || ball.center.y < 0) {
ballmovement.y = -1* ballmovement.y;
}
}
Edit: It seems like you carried the move method to the ball class, for limitations I can think o fthree alternatives:
Create two properties on the ball class named "maxX" and "maxY" during init/set after init and use them in the move method
Improve your move method with two parameters like
- (void)moveWithhinMaxX:(float)maxX andMaxY:(float)maxY;
and use them for limitation inside the move method
Improve your move method by giving the superview on the move method like:
- (void)moveWithinView:(float)newSuperview{
//[newSuperview addSubview:self]; add as subview if necessary
//Use newSuperview's bounds for limitations
and inside it you can add the ball as subview to superview and use its bounds for limitation