在碰撞檢測中調用CGRectIntersectsRect的問題

Question

我想在兩個imageView交叉時碰撞檢測。以下是我用於碰撞檢測的代碼。

- (void)onTimer 
{ 
// build a view from our flake image 
flakeView = [[UIImageView alloc] initWithImage:flakeImage]; 
flakeView.backgroundColor=[UIColor blueColor]; 

// use the random() function to randomize up our flake attributes 
int startX =round(random() % 460); 
printf("\n ===== startX :%d",startX); 
int endX = round(random() % 460); 
printf("\n ===== endX :%d",endX); 

double scale = 1/round(random() % 100) - 1.0; 
double speed = 1/round(random() %100) + 1.0; 

// set the flake start position 
flakeView.frame = CGRectMake(startX, -100.0, 25.0 * scale, 25.0 * scale); 
flakeView.alpha = 1.0; 

// put the flake in our main view 
[mView addSubview:flakeView]; 

[UIView beginAnimations:nil context:flakeView]; 
[UIView setAnimationDuration:20 * speed]; 


if(dragger.setFrame==YES) 

{ 

    printf("\n =====dragger.frame.origin.x:%f",dragger.frame.origin.x); 

    printf("\n =====dragger.frame.origin.y:%f",dragger.frame.origin.y); 

    flakeView.frame = CGRectMake(dragger.frame.origin.x, dragger.frame.origin.y, 25.0 * scale, 25.0 * scale); 

    printf("\n =====flakeView.frame.origin.x:%f",flakeView.frame.origin.x); 
    printf("\n =====flakeView.frame.origin.y:%f",flakeView.frame.origin.y); 



    if(CGRectIntersectsRect(flakeView.frame,dragger.frame)) 
    { 
     NSLog(@"\nRect is Intersecting"); 

    } 
    dragger.setFrame=NO; 
} 

else 
{ 
    flakeView.frame = CGRectMake(endX, 500.0, 25.0 * scale, 25.0 * scale); 


} 


[UIView setAnimationDidStopSelector:@selector(onAnimationComplete:finished:context:)]; 
[UIView setAnimationDelegate:self]; 
[UIView commitAnimations]; 

} 

在這個drager框架是一個inageView框架。當我們將此圖片拖到片狀圖像上時，方法

if(CGRectIntersectsRect(flakeView.frame,dragger.frame)) 

沒有被調用。 任何人都可以在這方面幫助..

在此先感謝。

Answer 1

你可以參考這裏....

sample code for collision detection in iPhone sdk