objective-c - For 循环会按照此模式在索引 : 0, 1 然后 1,2 然后 2,3 然后 3,4 处给我对象，直到数组计数？

Question

一段时间以来，我一直在尝试获得这些结果。我似乎无法弄清楚。有人知道怎么做吗？

我试图按照数组的开头到结尾将两个对象相互比较。

Tilo 的解决方案:

        for (int i=1; i<[tempRightArray count]; i++) {
            UIImageView* letterA = [tempRightArray objectAtIndex:i-1];
            UIImageView* letterB = [tempRightArray objectAtIndex:i];

            NSLog(@"LetterA: %@",letterA);
            NSLog(@"LetterB: %@",letterB);

            //Distance between right side of Touched piece and Left side of new piece == Touch on Right
            CGPoint midPointRightSidePiece = CGPointMake(CGRectGetMaxX(letterA.frame), CGRectGetMidY(letterA.frame));
            CGPoint midPointLeftSidepiece = CGPointMake(CGRectGetMinX(letterB.frame), CGRectGetMidY(letterB.frame));
            CGFloat distance = DistanceBetweenTwoPoints(midPointLeftSidepiece, midPointRightSidePiece);

            NSLog(@"Distance: %f",distance);

        }

更新了 Pauls block 解决方案:

    [tempRightArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {

        if (idx > 0) {

            UIImageView *letterB = (UIImageView*)obj;

            id obj2 = [tempRightArray objectAtIndex:--idx]; // idx is the index of obj again given to you by the block args

            UIImageView *letterA = (UIImageView*)obj2;

            NSLog(@"LetterA: %@",letterA);
            NSLog(@"LetterB: %@",letterB);

            //Distance between right side of Touched piece and Left side of new piece == Touch on Right
            CGPoint midPointRightSidePiece = CGPointMake(CGRectGetMaxX(letterA.frame), CGRectGetMidY(letterA.frame));
            CGPoint midPointLeftSidepiece = CGPointMake(CGRectGetMinX(letterB.frame), CGRectGetMidY(letterB.frame));
            CGFloat distance = DistanceBetweenTwoPoints(midPointLeftSidepiece, midPointRightSidePiece);

            NSLog(@"Distance: %f",distance);

        }

    }];

Answer 1

for (int i=1; i<[myArray count]; i++) {
  id obj1 = [myArray objectAtIndex:i-1];
  id obj2 = [myArray objectAtIndex:i];

  [self compare:obj1 to:obj2];
}