Question

我有一个对象，它是UIImageView的子类，用于检查另一个对象上的特定图像。如果有图像，ImageView会显示图像，否则会在下载新图像时显示临时图像。下载完成后，ImageView将显示新图像。这个对象我称之为“Imager”。

我在tableview中的单元格上实例化一个Imager。出于某种原因，成像器溢出了我的应用程序的内存。在Imager实现之前，应用程序的内存使用率大约为60Mb，但在实现后它会达到300Mb，因此我会收到内存警告，并且iPhone会关闭应用程序，就像预期一样。

我想知道，我做错了什么？这不是一个复杂的代码或逻辑，但我肯定在做一些提高内存的东西。我猜是桌面视图，但我不确定。

以下是Imager的代码： Imager.h

#import <UIKit/UIKit.h>
#import "friend.h"
#import "Group.h"
#import "Mimo.h"
@interface Imager : UIImageView
-(void)loadFriendImage:(friend*)theFriend;
-(void)loadGroupImage:(Group*)group;
@end

Imager.m

#import "Imager.h"
#import "Group.h"
@implementation Imager

-(void)loadFriendImage:(friend*)theFriend{
    if(!theFriend.flagDownloaded){
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^{
            dispatch_sync(dispatch_get_main_queue(), ^{
                if(theFriend.userImg == nil)
                    [self setImage:[UIImage imageNamed:@"default_image@2x.png"]];
                else{
                    [self setImage:theFriend.userImg];
                }
            });
            NSLog(@"[IMAGER]: Will load %@ image.",theFriend.username);
        UIImage *friendImage = [theFriend downloadImageBlocked];
        if(friendImage != nil){
            dispatch_sync(dispatch_get_main_queue(), ^{
                [self setImage:friendImage];
            });
        }


        });
    }
    else
    {
        NSLog(@"[IMAGER]: %@ image already exists",theFriend.username);
        if(self.image == nil)
            [self setImage:theFriend.userImg];
    }

}
-(void)loadGroupImage:(Group*)group
{
    if(!group.flagDownloaded){
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^{
            dispatch_sync(dispatch_get_main_queue(), ^{
                [self setImage:[UIImage imageNamed:@"default_image@2x.png"]];
            });
            NSLog(@"[IMAGER]: Will load %@ image.",group.groupName);
            UIImage *groupImage = [group downloadImageBlocked];
            if(groupImage != nil){
                dispatch_sync(dispatch_get_main_queue(), ^{
                    [self setImage:groupImage];
                });
            }


        });
    }
    else
    {
        [self setImage:group.groupImage];
    }
}

这是使用Imager对象的表

    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    {
        static NSString *CellIdentifier = @"friendCell";
        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

        if(cell == nil)
            cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];

    Imager *accessory;
    friend *workingFriend = [thisUser.friendsList objectAtIndex:indexPath.row];
    cell.textLabel.text = workingFriend.username;
    //----------------Setup Accessory View-----------------------------------

                    accessory = [[Imager alloc]init];
                    [accessory loadFriendImage:[thisUser.friendsList objectAtIndex:indexPath.row]];
                    accessory.frame = CGRectMake(cell.accessoryView.frame.origin.x, cell.accessoryView.frame.origin.y, 72.0, 72.0);
                    accessory.contentMode = UIViewContentModeScaleAspectFill;
                    accessory.clipsToBounds = YES;



                    cell.accessoryView = accessory;

                    cell.textLabel.textColor = [UIColor blackColor];
                    [cell.textLabel setFont:[UIFont fontWithName:@"HelveticaNeue" size:17]];
                    //----------------------------------------------------------
  return cell;
}

这是下载图像的下载图像功能

-(UIImage*)downloadImageBlocked
{
    NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:@"http://tatohouston.azurewebsites.net/getUserImg.php"]];
    [request setHTTPMethod:@"POST"];
    [request addValue:@"postValues" forHTTPHeaderField:@"METHOD"];
    NSDictionary *tempDic;

    //---------------------------------
    tempDic = @{@"userid":userID};
    //serialize the dictionary data as json
    NSData *dataPost = [[tempDic copy] JSONValue];
    [request setHTTPBody:dataPost]; //set the data as the post body

    [request addValue:[NSString stringWithFormat:@"%lu",(unsigned long)dataPost.length] forHTTPHeaderField:@"Content-Length"];

    NSData *tmpData = [[NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil] base64EncodedDataWithOptions:NSUTF8StringEncoding];
    if(tmpData != nil){
        returnData = [[NSData alloc]initWithBase64EncodedData:tmpData options:NSUTF8StringEncoding];
    }
    UIImage *friendImage;

    if(returnData != nil){
        friendImage = [UIImage imageWithData:returnData];
        userImg = friendImage;
        flagDownloaded = YES;
    }
    return friendImage;
}

Answer 1

从请求返回的NSData有多大？我发现它使用的是Base64编码数据，比一般来说未编码的数据大1.37倍。我的猜测是你的图像数据非常大。

自定义ImageView的内存溢出

1 个答案: