ios - 将 View 数加载到 UIScrollView 时由于内存错误而终止

Question

我在我的应用程序中使用 UIScrollView，第一次查看 25 次。

用户在 ScrollView 底部滚动下一个 25 个 View 。

我仍然完全不确定这是内存问题。但是我没有找到内存问题的代码原因。

即使我通过仪器工具检查内存泄漏问题也没有内存泄漏。

我的代码:

- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
        float scrollViewHeight = _scrl_ipad.frame.size.height;
        float scrollContentSizeHeight = _scrl_ipad.contentSize.height;
        float scrollOffset = _scrl_ipad.contentOffset.y;

        if (scrollOffset == 0)
        {

        }
        else if (scrollOffset + scrollViewHeight == scrollContentSizeHeight)
        {
            if (scrl_bottom_reload_view)
            {
                 scrl_bottom_reload_view=nil;
                [scrl_bottom_reload_view release];
            }

            scrl_bottom_reload_view = [[UIView alloc]initWithFrame:CGRectMake(10, scrollContentSizeHeight-100, _scrl_ipad.frame.size.width-20, 60.0)];
            scrl_bottom_reload_view.tag = -50;

            UILabel *lbl = [[UILabel alloc] initWithFrame:CGRectMake((_scrl_ipad.frame.size.width/2)-100, 10, 200, 40)];
            lbl.font = [UIFont fontWithName:@"ArialMT" size:22];
            lbl.textColor = [UIColor darkGrayColor];
            lbl.backgroundColor = [UIColor clearColor];
            lbl.text = @"Loading deals...";
            [scrl_bottom_reload_view addSubview:lbl];
            [lbl release];

            UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
            activityIndicator.alpha = 1.0;
            activityIndicator.color = [UIColor lightGrayColor];
            activityIndicator.frame = CGRectMake((_scrl_ipad.frame.size.width/2)-150, 12, 37, 37);
            activityIndicator.hidesWhenStopped = NO;
            [scrl_bottom_reload_view addSubview:activityIndicator];
            [activityIndicator startAnimating];


            scrl_bottom_reload_view.hidden = FALSE;
            scrl_bottom_reload_view.backgroundColor = [UIColor clearColor];

            [self.scrl_ipad addSubview:scrl_bottom_reload_view];

            [self performSelector:@selector(LoadScrl) withObject:nil afterDelay:0.3];
        }
}

    -(void)LoadScrl
    {
//called api and fill arrayalldeals arry

        [self func_scrl_ipad];
    }
-(void)func_scrl_ipad
{
        NSArray *viewsToRemove = [_scrl_ipad subviews];
        for (UIView *view in viewsToRemove)
        {
            [view removeFromSuperview];
            view = nil;
        }

        int temp;
        if([arrayalldeals count] % 2 == 0)
        {
            temp = ([arrayalldeals count] / 2);
        }
        else
        {
            temp = ([arrayalldeals count] / 2) + 1;
        }
        _scrl_ipad.contentSize = CGSizeMake(768,(258*temp)+150);
        _scrl_ipad.showsVerticalScrollIndicator=NO;



        int x = 35;
        int y = 35;
        for (int i = 1 ; i <= [arrayalldeals count]; i++)
        {
            UIView *bgview = [[UIView alloc]initWithFrame:CGRectMake(x, y, 328, 243)];
            bgview.backgroundColor = [UIColor whiteColor];
            //bgview.layer.borderWidth = 0;
            //bgview.layer.cornerRadius = 0;
            bgview.tag = i;
            //bgview.layer.masksToBounds = YES;
            //bgview.layer.borderColor =[[UIColor clearColor] CGColor];
            //bgview.layer.shadowColor = [[UIColor whiteColor] CGColor];
            //bgview.layer.shadowOffset = CGSizeMake(0.0, 0.0);
            //bgview.layer.shadowOpacity = 0.0;


            AsyncImageView *imageView = [[AsyncImageView alloc] initWithFrame:CGRectMake(0, 0, 328, 223)];
            imageView.contentMode = UIViewContentModeScaleAspectFill;
            imageView.clipsToBounds = YES;
            imageView.layer.cornerRadius = 0;
            imageView.imageURL =[NSURL URLWithString:[NSString stringWithFormat:@"%@uploads/%@-5.jpg",app.Main_url,[[arrayalldeals objectAtIndex:i-1] objectForKey:@"deal_id"]]];
            //cell.autoresizesSubviews=YES;
            [bgview addSubview:imageView];
            [imageView release];


            UIView *shadoeview = [[UIView alloc]initWithFrame:CGRectMake(0,115, 328, 112)];
            CAGradientLayer *bgLayer = [BackgroundLayer greyGradient];
            bgLayer.frame = shadoeview.bounds;
            [shadoeview.layer insertSublayer:bgLayer atIndex:0];
            shadoeview.alpha = 0.9;
            [bgview addSubview:shadoeview];
            [shadoeview release];

            UIImageView *img_discount = [[UIImageView alloc]initWithFrame:CGRectMake(0,0, 57, 57)];
            img_discount.image = [UIImage imageNamed:@"discount_tag.png"];
            [bgview addSubview:img_discount];
            [img_discount release];

            UILabel *lbl_disc_text=[[UILabel alloc]init];
            lbl_disc_text.frame=CGRectMake(-2,-10,100,20);
            lbl_disc_text.backgroundColor=[UIColor clearColor];
            lbl_disc_text.font = [UIFont fontWithName:@"ArialMT" size:14];
            lbl_disc_text.textColor = [UIColor whiteColor];
            int disc = 0;
            if([NSNull null] != [[arrayalldeals objectAtIndex:i-1] objectForKey:@"value"])
            {
                int main_price = [[[arrayalldeals objectAtIndex:i-1] objectForKey:@"value"] intValue];
                int disc_price = [[[arrayalldeals objectAtIndex:i-1] objectForKey:@"price"] intValue];
                int multiply = disc_price *100 /main_price;
                disc = 100 - multiply;
            }
            lbl_disc_text.text = [NSString stringWithFormat:@"- %d%%",disc];
            [bgview addSubview:lbl_disc_text];
            float degrees = -40; //the value in degrees
            lbl_disc_text.transform = CGAffineTransformMakeRotation(degrees * M_PI/180);
            [lbl_disc_text release];

            UILabel *lbl_desc=[[UILabel alloc]init];
            lbl_desc.frame=CGRectMake(8,162, 240, 50);
            lbl_desc.backgroundColor=[UIColor clearColor];
            lbl_desc.font = [UIFont fontWithName:@"Arial Rounded MT Bold" size:16];
            lbl_desc.textColor = [UIColor whiteColor];
            lbl_desc.numberOfLines = 2 ;
            if([NSNull null] != [[arrayalldeals objectAtIndex:i-1] objectForKey:@"name"])
            {
                lbl_desc.text=[NSString stringWithFormat:@"%@",[[arrayalldeals objectAtIndex:i-1] objectForKey:@"name"]];
            }
            else
            {
                lbl_desc.text=@"";
            }
            [bgview addSubview:lbl_desc];
            [lbl_desc release];

            UILabel *lbl_unprice=[[UILabel alloc]init];
            lbl_unprice.frame=CGRectMake(255,165,60,20);
            lbl_unprice.backgroundColor=[UIColor clearColor];
            lbl_unprice.textAlignment = NSTextAlignmentRight;
            lbl_unprice.textColor = [UIColor whiteColor];
            lbl_unprice.font = [UIFont fontWithName:@"ArialMT" size:14];
            if([NSNull null] != [[arrayalldeals objectAtIndex:i-1] objectForKey:@"value"])
            {
                int unprice = [[[arrayalldeals objectAtIndex:i-1] objectForKey:@"value"] intValue];
                lbl_unprice.text = [NSString stringWithFormat:@"$%d",unprice];
            }
            else
            {
                lbl_unprice.text=[NSString stringWithFormat:@"$0"];
            }
            [bgview addSubview:lbl_unprice];
            [lbl_unprice release];


            NSString *str_price_line;
            if([NSNull null] != [[arrayalldeals objectAtIndex:i-1] objectForKey:@"value"])
            {
                int unprice = [[[arrayalldeals objectAtIndex:i-1] objectForKey:@"value"] intValue];
                str_price_line = [NSString stringWithFormat:@"$%d",unprice];
            }
            else
            {
                str_price_line=[NSString stringWithFormat:@"$0"];
            }
            UIFont *font = [UIFont fontWithName:@"ArialMT" size:14];
            CGSize size = [(str_price_line ? str_price_line : @"") sizeWithFont:font constrainedToSize:CGSizeMake(281, 9999) lineBreakMode:NSLineBreakByWordWrapping];
            int temp = 60 - size.width;
            UILabel *lbl_line=[[UILabel alloc]init];
            lbl_line.frame=CGRectMake(253+temp,174,size.width+4,2);
            lbl_line.backgroundColor=[UIColor colorWithRed:252.0/255.0 green:36.0/255.0 blue:148.0/255.0 alpha:1.0];
            float degre = -20; //the value in degrees
            lbl_line.transform = CGAffineTransformMakeRotation(degre * M_PI/250);
            [bgview addSubview:lbl_line];
            [lbl_line release];

            UILabel *lbl_price=[[UILabel alloc]init];
            lbl_price.frame=CGRectMake(215,180, 100, 35);
            lbl_price.textAlignment = NSTextAlignmentRight;
            lbl_price.backgroundColor=[UIColor clearColor];
            lbl_price.font = [UIFont fontWithName:@"ArialMT" size:24];
            lbl_price.textColor = [UIColor colorWithRed:93.0/255.0 green:202.0/255.0 blue:242.0/255.0 alpha:1.0];
            if([NSNull null] != [[arrayalldeals objectAtIndex:i-1] objectForKey:@"price"])
            {
                int price = [[[arrayalldeals objectAtIndex:i-1] objectForKey:@"price"] intValue];
                lbl_price.text = [NSString stringWithFormat:@"$%d",price];
            }
            else
            {
                lbl_price.text=[NSString stringWithFormat:@"$0"];
            }
            [bgview addSubview:lbl_price];
            [lbl_price release];


            UILabel *lbl_bottom_view=[[UILabel alloc]init];
            lbl_bottom_view.frame=CGRectMake(0,223, 328,20);
            lbl_bottom_view.backgroundColor=[UIColor darkGrayColor];
            [bgview addSubview:lbl_bottom_view];
            [lbl_bottom_view release];

            UILabel *lbl_vertical1=[[UILabel alloc]init];
            lbl_vertical1.frame=CGRectMake(100,223,2,20);
            lbl_vertical1.backgroundColor=[UIColor grayColor];
            [bgview addSubview:lbl_vertical1];
            [lbl_vertical1 release];

            UILabel *lbl_vertical2=[[UILabel alloc]init];
            lbl_vertical2.frame=CGRectMake(222,223,2,20);
            lbl_vertical2.backgroundColor=[UIColor grayColor];
            [bgview addSubview:lbl_vertical2];
            [lbl_vertical2 release];

            UILabel *lbl_address=[[UILabel alloc]init];
            lbl_address.frame=CGRectMake(4,226, 94, 14);
            lbl_address.textAlignment = NSTextAlignmentCenter;
            lbl_address.backgroundColor=[UIColor clearColor];
            lbl_address.font = [UIFont fontWithName:@"ArialMT" size:12];
            lbl_address.textColor = [UIColor whiteColor];
            if ((NSNull *)app.city_dict == NULL)
            {
                lbl_address.text= @"Vancouver";
            }
            else
            {
                lbl_address.text=[NSString stringWithFormat:@"%@",[app.city_dict objectForKey:@"title"]];
            }
            [bgview addSubview:lbl_address];
            [lbl_address release];


            //LeftTime
            NSString *strDatehere = [NSString stringWithFormat:@"%@",[[arrayalldeals objectAtIndex:i-1] objectForKey:@"d_expires"]];
            NSDateFormatter *heredateFormatter = [[NSDateFormatter alloc] init];
            [heredateFormatter setDateFormat:@"yyyy-MM-dd"]; // set date formate with your dates

            NSDate *datehere = [heredateFormatter dateFromString: strDatehere];
            NSTimeInterval timeDifference = [datehere timeIntervalSinceDate:[NSDate date]];
            [heredateFormatter release];

            double hours = timeDifference / 3600;
            NSInteger remainder = ((NSInteger)timeDifference)% 3600;
            double minutes = remainder / 60;
            double seconds = remainder % 60;

            NSString *strleft_time = [NSString stringWithFormat:@"%.0fh, %.0fm, %.0fs",hours,minutes,seconds];

            UILabel *lbl_time=[[UILabel alloc]init];
            lbl_time.frame=CGRectMake(105,226, 110, 14);
            lbl_time.textAlignment = NSTextAlignmentCenter;
            lbl_time.backgroundColor=[UIColor clearColor];
            lbl_time.font = [UIFont fontWithName:@"ArialMT" size:12];
            lbl_time.textColor = [UIColor whiteColor];
            lbl_time.text=strleft_time;
            [bgview addSubview:lbl_time];
            [lbl_time release];

            UILabel *lbl_bought=[[UILabel alloc]init];
            lbl_bought.frame=CGRectMake(222,226, 98, 14);
            lbl_bought.textAlignment = NSTextAlignmentCenter;
            lbl_bought.backgroundColor=[UIColor clearColor];
            lbl_bought.font = [UIFont fontWithName:@"ArialMT" size:12];
            lbl_bought.textColor = [UIColor whiteColor];
            lbl_bought.text= [NSString stringWithFormat:@"%@ Bought",[[arrayalldeals objectAtIndex:i-1] objectForKey:@"buys"]];
            [bgview addSubview:lbl_bought];
            [lbl_bought release];


            UIButton *btn_scrl=[UIButton buttonWithType:UIButtonTypeCustom];
            [btn_scrl setFrame:CGRectMake(0,0, 328, 243)];
            btn_scrl.tag=i-1;
            [btn_scrl addTarget:self action:@selector(btn_scrl_tag:) forControlEvents:UIControlEventTouchUpInside];
            [bgview addSubview:btn_scrl];


            UIButton *btn_fav=[UIButton buttonWithType:UIButtonTypeCustom];
            [btn_fav setFrame:CGRectMake(285,5, 35, 35)];
            if([[[arrayalldeals objectAtIndex:i-1] objectForKey:@"user_faves"] isEqualToString:@"1"])
            {
                [btn_fav setBackgroundImage:[UIImage imageNamed:@"all_deals_fave_pink_icon.png"] forState:UIControlStateNormal];
            }
            else
            {
                [btn_fav setBackgroundImage:[UIImage imageNamed:@"all_deals_fave_icon.png"] forState:UIControlStateNormal];
            }
            [btn_fav.titleLabel setFont:[UIFont boldSystemFontOfSize:12]];
            if([[[arrayalldeals objectAtIndex:i-1] objectForKey:@"faves"] isEqualToString:@"0"])
            {
                [btn_fav setTitle:@"" forState:UIControlStateNormal];
            }
            else
            {
                [btn_fav setTitle:[NSString stringWithFormat:@"%@",[[arrayalldeals objectAtIndex:i-1] objectForKey:@"faves"]] forState:UIControlStateNormal];
            }
            btn_fav.tag=i-1;
            [btn_fav addTarget:self action:@selector(btn_favorite:) forControlEvents:UIControlEventTouchUpInside];
            [bgview addSubview:btn_fav];

            [_scrl_ipad addSubview:bgview];
            [bgview release];



            if(i % 2 == 0)
            {
                y = y + 258;
                x = 35;
            }
            else
            {
                x = 399;
            }
        }
    }
}

////现在 api 调用了 10 次以上，由于内存压力错误和应用程序崩溃，我被终止了

Answer 1

没看懂，你想做什么？但是在你的代码中发现了很多错误。列出其中的一些。

1) 在这一行中，您已经设置为 nil 并尝试释放 nil 对象。这不会释放任何对象，这是内存泄漏的主要原因。

       if (scrl_bottom_reload_view)
        {
             scrl_bottom_reload_view=nil;
            [scrl_bottom_reload_view release];
        }

2) 尝试将 nil 分配给什么都不做的局部变量。

 for (UIView *view in viewsToRemove)
    {
        [view removeFromSuperview];
        view = nil;
    }

3) 你在哪里释放这个对象。

UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc].....

建议:上面的代码比较复杂，用Tableview试试。使用 xib 为这份工作点赞。否则设计更复杂，开发时间也更长。