获取iPod库中项目的专辑年份? [英] Get album year for item in iPod library?
本文介绍了获取iPod库中项目的专辑年份?的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
尝试以下代码:
// Per albums
MPMediaQuery *albumsQuery = [MPMediaQuery albumsQuery];
NSArray *collections = [albumsQuery collections];
for (MPMediaItemCollection *collection in collections)
{
NSDate *collectionReleaseDate = [collection valueForProperty: MPMediaItemPropertyReleaseDate];
NSLog(@"collection release date: %@", collectionReleaseDate);
MPMediaItem *representativeItem = [collection representativeItem];
NSDate *representativeItemReleaseDate = [representativeItem valueForProperty: MPMediaItemPropertyReleaseDate];
NSLog(@"representativeItem release date: %@", representativeItemReleaseDate);
}
// Just per item
MPMediaQuery *query = [[MPMediaQuery alloc] init];
NSArray *items = [query items];
for (MPMediaItem *item in items)
{
NSDate *date = [item valueForProperty: MPMediaItemPropertyReleaseDate];
NSLog(@"release date: %@", date);
}
在所有情况下,我获得NSDates的nil's ...
但是在iPod库中,我可以看到日期,因此必须提供信息。
获得它的正确方法是什么?
In all cases I get nil's for NSDates... But in the iPod library I can see dates, so the information must be available. What is the correct way to obtain it?
推荐答案
嗯,我想我已经弄明白了。我以为iTunes中的'Year'列对应于API中的MPMediaItemPropertyReleaseDate - 但这是错误的。我的物品实际上没有发布日期信息。
Well, I think I've figured it out. I was thinking that 'Year' column in iTunes corresponds to MPMediaItemPropertyReleaseDate in API - but it's wrong. My items actually weren't having release date info.
我还找到了如何获取'年'信息(我需要的),但不幸的是没有记录:
I also found how to obtain 'Year' information (which I needed), but unfortunately in undocumented way:
MPMediaItem *item = ...;
NSNumber *yearNumber = [item valueForProperty:@"year"];
if (yearNumber && [yearNumber isKindOfClass:[NSNumber class]])
{
int year = [yearNumber intValue];
if (year != 0)
{
// do something with year
}
}
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