如何在ios

Question

我从服务器加载了XML数据（包括图像，文本......），并通过tableview显示该数据。

- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName 
namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
if([elementName isEqualToString:@"user_id"])
{
    Myxml.str_user_id = currentNodeContent;
}

else if([elementName isEqualToString:@"username"])
{
    Myxml.str_username = currentNodeContent;

}
else if([elementName isEqualToString:@"avatar"])
{
    Myxml.str_avatar=currentNodeContent;
    Myxml.imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:currentNodeContent]];

}
else if([elementName isEqualToString:@"full_name"])
{
    Myxml.str_full_name=currentNodeContent;

}
else if([elementName isEqualToString:@"cups"])
{
    Myxml.str_cups=currentNodeContent; 
}
//--------Record End-------
else if([elementName isEqualToString:@"record"])
{
    [RecordArray addObject:Myxml];
    [Myxml release];
    Myxml = nil;        
}

[currentNodeContent release];
currentNodeContent = nil;
currentNodeContent = [[NSMutableString alloc]init];

}

现在，在主视图控制器中，我收集名为＆＃34; LabelArray＆＃34;的NSMutableArray中的所有数据。在init方法

Connection=[[NetworkConnection alloc]initConnection];

if (Connection.isReachable)
{
    XmlDetail=[[TopPickerXML alloc]init];

    LabelArray=[[NSMutableArray alloc]initWithArray:XmlDetail.RecordArray];
}
else
{
    UIAlertView *alert=[[UIAlertView alloc]initWithTitle:@"Alert" message:@"Network connection unavailable..." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [alert show];
    [alert release];
}

在cellForRowAtIndexPath的Table视图中，我显示这样的图像

img_BuddyAvtar=[[UIImageView alloc]init];
img_BuddyAvtar.frame=CGRectMake(10, 5, 120, 105);
img_BuddyAvtar.image=[UIImage imageWithData:TopPicker_record.imageData];
img_BuddyAvtar.backgroundColor=[UIColor clearColor];
[View_TableCell addSubview:img_BuddyAvtar];

现在，我的问题是，当我加载此视图时，需要时间来加载，然后显示包括我的文本和图像在内的所有数据。我如何预加载图像以便加载表格视图所需的时间更短？

Answer 1

您必须缓存图片。

1. 将SDWebImage添加到项目中。
2. 导入cellForItemAtIndexPath标题

3. 在[cell.imageView sd_setImageWithURL:[NSURL URLWithString:@"your image URL"] placeholderImage:[UIImage imageNamed:@"placeholder.png"]];

   添加以下代码

   SELECT  b.Series,
           CASE 
               WHEN Series = 'DMS' THEN ROUND(b.Quantity,0)
               ELSE ROUND(b.Quantity,2)
           END AS Quantity
           FROM bill b