iOS的相簿建立与图片保存

作品链接:http://www.jianshu.com/users/1e0f5e6f73f6/top_articles


1.导入第三方框架SVProgressHUD 和 Photos框架


#import

#import




2.创建全局变量相簿的名称

static NSString * PHAssetCollectionTitle = @"卡卡";


3.保存按钮

- (IBAction)save {

// 判断授权状态

PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];

if (status == PHAuthorizationStatusRestricted) {

[SVProgressHUD showErrorWithStatus:@"因为系统原因,无法访问相册"];

} else if (status == PHAuthorizationStatusDenied){

// 用户拒绝当前应用访问相册(用户当初点击了"不允许")

NSLog(@"提醒用户去[设置-隐私-照片-xxx]打开访问开关");

} else if (status == PHAuthorizationStatusAuthorized){

//用户允许当前应用访问相册  用户当初点击了好

[self saveImage];

} else if (status == PHAuthorizationStatusNotDetermined){

// 用户还没有做出选择

// 弹框请求用户授权

[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) {

if (status == PHAuthorizationStatusAuthorized) {

[self saveImage];

}

}];

}

}


4.保存图片

- (void)saveImage

{

// PHAsset : 一个资源, 比如一张图片\一段视频

// PHAssetCollection : 一个相簿

// PHAsset的标识,利用这个标识可以找到对应的PHAsset对象 即图片对象

__block NSString *assetLocalIdentifier = nil;

// 如果想对"相册"进行修改(增删改), 那么修改代码必须放在[PHPhotoLibrary sharedPhotoLibrary]的performChanges方法的block中

[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{

//1.保存图片A到【相机胶卷】中

// 创建图片的请求

assetLocalIdentifier = [PHAssetCreationRequest creationRequestForAssetFromImage:self.imageView.image].placeholderForCreatedAsset.localIdentifier;

} completionHandler:^(BOOL success, NSError * _Nullable error) {

if (success == NO) {

[self showError:@"保存图片失败"];

return ;

}

// 2.获得相簿

PHAssetCollection *createdAssetCollection = [self createdAssetCollection];

if (createdAssetCollection == nil) {

[self showError:@"保存图片失败"];

return ;

}

[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{

// 获得图片

PHAsset *asset = [PHAsset fetchAssetsWithLocalIdentifiers:@[assetLocalIdentifier] options:nil].lastObject;

// 添加图片到相簿中的请求

PHAssetCollectionChangeRequest *request = [PHAssetCollectionChangeRequest changeRequestForAssetCollection:createdAssetCollection];

// 添加图片到相簿

[request addAssets:@[asset]];

} completionHandler:^(BOOL success, NSError * _Nullable error) {

if (success == NO) {

[self showError:@"保存图片失败"];

} else{

[self showSuccess:@"保存图片成功"];

}

}];

}];

}


5.获得相簿

- (PHAssetCollection *)createdAssetCollection{  

  PHFetchResult*assetCollections = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];

for (PHAssetCollection *assetCollection in assetCollections) {

if ([assetCollection.localizedTitle isEqualToString:PPHAssetCollectionTitle]) {

return assetCollection;

}

}

// 没有找到对应的相簿, 得创建新的相簿

// 错误信息

NSError *error = nil;

// PHAssetCollection的标识,利用这个标识可以找到对应的PHAssetCollection的对象(相簿对象)

__block NSString *assetCollectionLocalIdentifier = nil;

[[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{

// 创建相簿的请求

assetCollectionLocalIdentifier = [PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:PPHAssetCollectionTitle].placeholderForCreatedAssetCollection.localIdentifier;

} error:&error];

if (error) return nil;

// 获得刚才创建的相簿

PHAssetCollection *assetCollection = [PHAssetCollection fetchAssetCollectionsWithLocalIdentifiers:@[assetCollectionLocalIdentifier] options:nil].lastObject;

return assetCollection;

}


6.保存成功方法

- (void)showSuccess:(NSString *)text

{

dispatch_async(dispatch_get_main_queue(), ^{

[SVProgressHUD showSuccessWithStatus:text];

});

}


7.保存失败方法

- (void)showError:(NSString *)text

{

dispatch_async(dispatch_get_main_queue(), ^{

[SVProgressHUD showErrorWithStatus:text];

});

}

你可能感兴趣的:(iOS的相簿建立与图片保存)