UIImageView的實例不會保存一個image file翩腐，它顯示的是一個UIImage實例鸟款。當給UIImageView設(shè)置imageNamed后，無法再從UIImageView實例獲取fileName茂卦。
1.從UIImageView繼承一個subclass何什，設(shè)置一個NSString * imageFileName；屬性
和setImage方法：
-(void) setImage:(NSString*)fileName
{
imageFileName = fileName;
[super setImage:fileName];
}
2.使用accessibilityIdntifier
通過下面setAccessibilityIdentifier
[_checkImageView.image setAccessibilityIdentifier:@"yixuan"];
NSString *file_name = [_checkImageView.image accessibilityIdentifier] ;
// 判斷當前是已選還是未選中狀態(tài)
if ([_checkImageView.image.accessibilityIdentifier isEqualToString:@"yixuan"]) {
_checkImageView.image = [UIImage imageNamed:@"weixuan"];
_checkImageView.image.accessibilityIdentifier = @"weixuan";
}else {
_checkImageView.image = [UIImage imageNamed:@"yixuan"];
_checkImageView.image.accessibilityIdentifier = @"yixuan";
}
