小编EHN*_*ole的帖子

在我的应用程序中,我允许用户通过Instagram共享照片,这需要使用UIDocumentInteractionController.如果手机支持,则会自动检测到Airdrop.如何从"打开方式"操作表中删除它？

即使我使用UIActivityViewController开始共享过程并调用setExcludedActivityTypes:,最终我必须使用UIDocumentInteractionController,当我这样做时,Airdrop再次出现.以下是分享按钮时的代码:

NSURL *instagramURL = [NSURL URLWithString:@"instagram://location?id=1"];

if ([[UIApplication sharedApplication] canOpenURL:instagramURL]) {
    NSString *documentsDirectory = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];
    NSString *savedImagePath = [documentsDirectory stringByAppendingPathComponent:@"Image.igo"];

    NSData *imageData = UIImagePNGRepresentation(imageToShare);
    [imageData writeToFile:savedImagePath atomically:YES];
    NSURL *imageUrl = [NSURL fileURLWithPath:savedImagePath];
    docController = [[UIDocumentInteractionController alloc] init];
    docController.UTI = @"com.instagram.exclusivegram";
    docController.URL = imageUrl;
    [docController presentOpenInMenuFromRect:CGRectZero inView:self.view animated:YES];

}
else
{
    NSLog(@"no insta");
}

我需要找到每个嵌套元素的第二个和第三个元素之间的距离

nested_array = [[0, 3, 4], [1, 20, 21], [2, 2, 2]]

def pythag_theorem(a, b)
    c = (a * a) + (b * b)
    result = Math.sqrt(c)
    result
end

def find_distance(array)
  t = 0
  while t < array.length
    array[t].map! {|x| pythag_theorem(x[1], x[2])}
  t += 1
  end
array
end

print find_distance(nested_array)

我越来越

[[0.0, 1.4142135623730951, 0.0], [1.0, 0.0, 1.0], [1.0, 1.0, 1.0]]

当我需要

[[0, 5], [1, 29], [2, 2.82842712474619]]

pythag_theorem 有效，但为什么不是 map！为我工作？谢谢。