Time Profiler分析的審閱方法

Question

我已經使用了Time Profiler Instrument來識別我的應用程序中的明顯滯后。 現在我知道了問題所在，但是我不知道該怎么辦。 我正在使用ARC，並且有一個viewController，它調用方法“ Go”，如下所示。 我還包括了時間分析器結果的快照。 有誰知道我該怎么解決？ 謝謝！

這是該方法的代碼：

- (void)go {

CGFloat width = self.imageViewA.bounds.size.width;

[UIView animateWithDuration:18.0 delay:0.0 options:UIViewAnimationOptionCurveLinear 
animations:^ {
    self.imageViewA.frame = CGRectOffset(self.imageViewA.frame, -width, 0);
    self.imageViewB.frame = CGRectOffset(self.imageViewB.frame, -width, 0);
    } 
completion:^(BOOL finished) {
    if (self.keepGoing) {
        // now B is where A began, so swap them and reposition B
        UIImageView *temp = self.imageViewA;
        self.imageViewA  = self.imageViewB;
        self.imageViewB = temp;
        self.imageViewB.frame = CGRectOffset(self.view.bounds, 
        self.view.bounds.size.width, 0.0);
        // recursive call, but we don't want to wind up the stack
        [self performSelector:@selector(go) withObject:nil afterDelay:0.0];
        }
    }];
}

這是我的時間檔案的結果：

作為參考，我也包括了我的.h文件。

@interface ViewController : GAITrackedViewController

@property (weak, nonatomic) IBOutlet UIBarButtonItem *lButton;
@property (weak, nonatomic) IBOutlet UIBarButtonItem *rButton;

@property (nonatomic, assign) BOOL keepGoing;
@property (nonatomic, strong) UIImageView *imageViewA;
@property (nonatomic, strong) UIImageView *imageViewB;

- (IBAction)handleLPressed:(id)sender;
- (IBAction)handleRPressed:(id)sender;
@end

Answer 1

也許這可以工作：

- (void)go {

CGFloat width = self.imageViewA.bounds.size.width;

__weak typeof(self) self_ = self;

[UIView animateWithDuration:18.0 delay:0.0 options:UIViewAnimationOptionCurveLinear 
animations:^ {
    __strong typeof(self) self = self_;
    self.imageViewA.frame = CGRectOffset(self.imageViewA.frame, -width, 0);
    self.imageViewB.frame = CGRectOffset(self.imageViewB.frame, -width, 0);
    } 
completion:^(BOOL finished) {
    __strong typeof(self) self = self_;
    if (self.keepGoing) {
        // now B is where A began, so swap them and reposition B
        UIImageView *temp = self.imageViewA;
        self.imageViewA  = self.imageViewB;
        self.imageViewB = temp;
        self.imageViewB.frame = CGRectOffset(self.view.bounds, 
        self.view.bounds.size.width, 0.0);
        // recursive call, but we don't want to wind up the stack
        [self performSelector:@selector(go) withObject:nil afterDelay:0.0];
        }
    }];
}

這樣做是保持對self的弱引用，而不是將其復制到塊中的堆棧中。 我不確定，但是也許可以。