#import "XMGSeeBigPictureViewController.h"
#import "XMGTopic.h"
#import <SVProgressHUD.h>
#import <Photos/Photos.h>
@interface XMGSeeBigPictureViewController () <UIScrollViewDelegate>
@property (weak, nonatomic) IBOutlet UIButton *saveButton;
@property (nonatomic, weak) UIScrollView *scrollView;
@property (nonatomic, weak) UIImageView *imageView;
/** 当前App对应的自定义相册 */
- (PHAssetCollection *)createdCollection;
/** 返回刚才保存到【相机胶卷】的图片 */
- (PHFetchResult<PHAsset *> *)createdAssets;
@end
@implementation XMGSeeBigPictureViewController
- (void)viewDidLoad {
[super viewDidLoad];
// scrollView
UIScrollView *scrollView = [[UIScrollView alloc] init];
scrollView.frame = [UIScreen mainScreen].bounds;
[scrollView addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(back)]];
[self.view insertSubview:scrollView atIndex:0];
self.scrollView = scrollView;
// imageView
UIImageView *imageView = [[UIImageView alloc] init];
[imageView sd_setImageWithURL:[NSURL URLWithString:self.topic.image1] completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
if (!image) return;
self.saveButton.enabled = YES;
}];
imageView.xmg_width = scrollView.xmg_width;
imageView.xmg_height = imageView.xmg_width * self.topic.height / self.topic.width;
imageView.xmg_x = 0;
if (imageView.xmg_height > XMGScreenH) { // 超过一个屏幕
imageView.xmg_y = 0;
scrollView.contentSize = CGSizeMake(0, imageView.xmg_height);
} else {
imageView.xmg_centerY = scrollView.xmg_height * 0.5;
}
[scrollView addSubview:imageView];
self.imageView = imageView;
// 图片缩放
CGFloat maxScale = self.topic.width / imageView.xmg_width;
if (maxScale > 1) {
scrollView.maximumZoomScale = maxScale;
scrollView.delegate = self;
}
}
#pragma mark - <UIScrollViewDelegate>
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
return self.imageView;
}
#pragma mark - 获得当前App对应的自定义相册
- (PHAssetCollection *)createdCollection
{
// 获得软件名字
NSString *title = [NSBundle mainBundle].infoDictionary[(__bridge NSString *)kCFBundleNameKey];
// 抓取所有的自定义相册
PHFetchResult<PHAssetCollection *> *collections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
// 查找当前App对应的自定义相册
for (PHAssetCollection *collection in collections) {
if ([collection.localizedTitle isEqualToString:title]) {
return collection;
}
}
/** 当前App对应的自定义相册没有被创建过 **/
// 创建一个【自定义相册】
NSError *error = nil;
__block NSString *createdCollectionID = nil;
[[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
createdCollectionID = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:title].placeholderForCreatedAssetCollection.localIdentifier;
} error:&error];
if (error) return nil;
// 根据唯一标识获得刚才创建的相册
return [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[createdCollectionID] options:nil].firstObject;
}
- (PHFetchResult<PHAsset *> *)createdAssets
{
NSError *error = nil;
__block NSString *assetID = nil;
// 保存图片到【相机胶卷】
[[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
assetID = [PHAssetChangeRequest creationRequestForAssetFromImage:self.imageView.image].placeholderForCreatedAsset.localIdentifier;
} error:&error];
if (error) return nil;
// 获取刚才保存的相片
return [PHAsset fetchAssetsWithLocalIdentifiers:@[assetID] options:nil];
}
#pragma mark - 监听点击
- (IBAction)back {
[self dismissViewControllerAnimated:YES completion:nil];
}
- (IBAction)save {
PHAuthorizationStatus oldStatus = [PHPhotoLibrary authorizationStatus];
// 请求检查访问权限 :
// 如果用户还没有做出选择,会自动弹框,用户对弹框做出选择后,才会调用block
// 如果之前已经做过选择,会直接执行block
[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {
dispatch_async(dispatch_get_main_queue(), ^{
if (status == PHAuthorizationStatusDenied) { // 用户拒绝当前App访问相册
if (oldStatus != PHAuthorizationStatusNotDetermined) {
XMGLog(@"提醒用户打开开关")
}
} else if (status == PHAuthorizationStatusAuthorized) { // 用户允许当前App访问相册
[self saveImageIntoAlbum];
} else if (status == PHAuthorizationStatusRestricted) { // 无法访问相册
[SVProgressHUD showErrorWithStatus:@"因系统原因,无法访问相册!"];
}
});
}];
}
/**
* 保存图片到相册
*/
- (void)saveImageIntoAlbum
{
// 获得相片
PHFetchResult<PHAsset *> *createdAssets = self.createdAssets;
if (createdAssets == nil) {
[SVProgressHUD showErrorWithStatus:@"保存图片失败!"];
return;
}
// 获得相册
PHAssetCollection *createdCollection = self.createdCollection;
if (createdCollection == nil) {
[SVProgressHUD showErrorWithStatus:@"创建或者获取相册失败!"];
return;
}
// 添加刚才保存的图片到【自定义相册】
NSError *error = nil;
[[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
PHAssetCollectionChangeRequest *request = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:createdCollection];
[request insertAssets:createdAssets atIndexes:[NSIndexSet indexSetWithIndex:0]];
} error:&error];
// 最后的判断
if (error) {
[SVProgressHUD showErrorWithStatus:@"保存图片失败!"];
} else {
[SVProgressHUD showSuccessWithStatus:@"保存图片成功!"];
}
}
@end