Question

尝试使用以下代码将图像保存在iphone库中，但在模拟器中工作正常，而不是在iphone中。

-(void)saveTkt
{
UIWindow *keyWindow = [[UIApplication sharedApplication] keyWindow];
CGRect rect = [keyWindow bounds];
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[keyWindow.layer renderInContext:context];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData * data = UIImagePNGRepresentation(img);
[data writeToFile:@"f.png" atomically:YES];

UIImageWriteToSavedPhotosAlbum(img, self, @selector(thisImage:hasBeenSavedInPhotoAlbumWithError:usingContextInfo:), nil);
}

已编辑的代码

-(void)saveTkt
{
UIWindow *keyWindow = [[UIApplication sharedApplication] keyWindow];
CGRect rect = [keyWindow bounds];
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[keyWindow.layer renderInContext:context];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData * data = UIImagePNGRepresentation(img);
[data writeToFile:@"f.png" atomically:YES];

ALAuthorizationStatus status = [ALAssetsLibrary authorizationStatus];
if (status != ALAuthorizationStatusAuthorized) {
    //show alert for asking the user to give permission

}

//UIImageWriteToSavedPhotosAlbum(img, self, @selector(thisImage:hasBeenSavedInPhotoAlbumWithError:usingContextInfo:), nil);

ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];

[library writeImageToSavedPhotosAlbum:[img CGImage] orientation:(ALAssetOrientation)[img imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){
    if (error) {
        // TODO: error handling
        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"error" message:[error localizedDescription] delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
    } else {
        // TODO: success handling
        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"alert" message:@"Saved suceesfully in photos album." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
    }
}];

ALAssetsLibraryGroupsEnumerationResultsBlock assetGroupEnumerator =
^(ALAssetsGroup *assetGroup, BOOL *stop) {
    if (assetGroup != nil) {
        // do somthing
    }
};

ALAssetsLibraryAccessFailureBlock assetFailureBlock = ^(NSError *error) {
    NSLog(@"Error enumerating photos: %@",[error description]);

};

NSUInteger groupTypes = ALAssetsGroupAll;

[library enumerateGroupsWithTypes:groupTypes usingBlock:assetGroupEnumerator failureBlock:assetFailureBlock];

}

Answer 1

添加Framework assetsLibrary

 ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];

[library writeImageToSavedPhotosAlbum:[image CGImage] orientation:(ALAssetOrientation)[image imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){
if (error) {
// TODO: error handling
} else {
// TODO: success handling
}
}];
[library release];

Answer 2

Apple's documentation say that the completion handler must conform to this:

- (void) image: (UIImage *) image didFinishSavingWithError: (NSError *) error contextInfo: (void *) contextInfo;

并且传递了一个错误参数，您应该打印出来以查看实际的真实错误。

例如：

- (void) image: (UIImage *) image didFinishSavingWithError: (NSError *) error contextInfo: (void *) contextInfo
{
    if(error != NULL)
    {
        NSLog( @"error while saving image is %@", [error localizedDescription]);
    }
}

Answer 3

我认为你应该首先尝试使用NSData，或者你可以在没有NSData的情况下使用NSData

NSData *dataImage = UIImageJPEGRepresentation(file,1);
UIImageView *img;
img.image = [[UIImage alloc] initWithData:dataImage];
 UIImageWriteToSavedPhotosAlbum( [[UIImage alloc] initWithData:dataImage], nil, nil, nil);

希望，它会起作用

图像保存在模拟器库中但不保存在iphone库中

3 个答案: