Question

关于这个问题，我在这里经历了不少线程，但没有取得多大成功。

我正在浏览网站上的图片，点按并显示我的操作表，保存照片或取消。它确实保存，但它保存了白色图像，而不是图像本身。我试过的另一种方法只保存为屏幕截图（不是我想要的）。

我不是在拍摄特定图像，而是拍摄任何格式的图像。

这是我正在使用的所有当前代码。

    UILongPressGestureRecognizer *gestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handleLongPress:)];
    webView.userInteractionEnabled = YES;
    gestureRecognizer.minimumPressDuration = 0.3;
    gestureRecognizer.delegate = self;
    gestureRecognizer.numberOfTouchesRequired = 1;
    [webView addGestureRecognizer:gestureRecognizer];

}

- (void)handleLongPress:(UILongPressGestureRecognizer*)gestureRecognizer{
    if (gestureRecognizer.state == UIGestureRecognizerStateBegan){
        //get the image view that the user selected and save it as your selectedImageView property
        UIImageView *pressedImageView = (UIImageView *)gestureRecognizer.view;
        self.selectedImageView = pressedImageView;

        UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:nil delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:nil otherButtonTitles:@"Save Photo", nil];
        actionSheet.actionSheetStyle = UIActionSheetStyleBlackTranslucent;
        [actionSheet showInView:self.view];
        [actionSheet release];

    }}

-(void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
    switch (buttonIndex) {
        case 0:

            [self savePhoto];

            break;

        default:
            break;

    }}

-(void)savePhoto{

    UIGraphicsBeginImageContext(_selectedImageView.bounds.size);
    [_selectedImageView drawRect:_selectedImageView.bounds];
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    UIImageWriteToSavedPhotosAlbum(image,
                                   self,
                                   @selector(savedPhotoImage:didFinishSavingWithError:contextInfo:),
                                   NULL);


}

- (void)   savedPhotoImage:(UIImage *)image
  didFinishSavingWithError:(NSError *)error
               contextInfo:(void *)contextInfo
{
    NSString *message = @"This image has been saved to your Photos album";
    if (error) {
        message = [error localizedDescription];
    }
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
                                                    message:message
                                                   delegate:nil
                                          cancelButtonTitle:@"OK"
                                          otherButtonTitles:nil];
    [alert show];
    [alert release];
}

我相信savePhoto正在搞乱。

先谢谢你。

更新：所以这说它保存了它，但没有任何显示。

-(void)savePhoto {

    NSLog(@"TAPPED");
    //Touch gestures below top bar should not make the page turn.
    //EDITED Check for only Tap here instead.
        CGPoint touchPoint = [touch locationInView:self.view];

        NSUserDefaults * userDefaults = [NSUserDefaults standardUserDefaults];
        bool pageFlag = [userDefaults boolForKey:@"pageDirectionRTLFlag"];
        NSLog(@"pageFlag tapbtnRight %d", pageFlag);

            NSString *imgURL = [NSString stringWithFormat:@"document.elementFromPoint(%f, %f).src", touchPoint.x, touchPoint.y];
            NSString *urlToSave = [webView stringByEvaluatingJavaScriptFromString:imgURL];
            NSLog(@"urlToSave :%@",urlToSave);
            NSURL * imageURL = [NSURL URLWithString:urlToSave];
            NSData * imageData = [NSData dataWithContentsOfURL:imageURL];
            UIImage * image = [UIImage imageWithData:imageData];
            imageView.image = image;//imgView is the reference of UIImageView

            UIImageWriteToSavedPhotosAlbum(image,
                                           self,
                                           @selector(savedPhotoImage:didFinishSavingWithError:contextInfo:),
                                           NULL);
}

Answer 1

决定回到此，因为我正在处理我的应用中的其他事情。决定采取不同的方法。而不是试图发现触摸或其他什么。我只是调用保存操作将图像下载到相机胶卷。现在很简单，我可以看到它是如何工作的。如果有人好奇，我就是这样做的。

总结一下，在我的webview中，我创建了一个可以打开图像扩展的控制器。在我看来，更容易本地化它。从那里，我在导航栏中添加了一个保存按钮。从那以后我做了什么。

-(void)savePhoto {
   NSURL *imageURL = receivedURL;
    UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:imageURL]];
    UIImageWriteToSavedPhotosAlbum(image, self, @selector(savedPhotoImage:didFinishSavingWithError:contextInfo:), nil);
    [UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
}

- (void)   savedPhotoImage:(UIImage *)image
  didFinishSavingWithError:(NSError *)error
               contextInfo:(void *)contextInfo
{
   UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
                                                    message:@"This image has been saved to your camera roll"
                                                   delegate:nil
                                          cancelButtonTitle:@"OK"
                                          otherButtonTitles:nil];
    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
    [alert show];
    [alert release];    
}

希望这有助于某人：）

Answer 2

当您请求gestureRecognizer.view时，您将获得网络视图，而不是您认为的图像视图。手势识别器返回它所连接的视图，而不是被轻击的视图。

此外，将视图绘制到图像中的正确方法是使用视图图层：

[_selectedImageView.layer renderInContext:UIGraphicsGetCurrentContext()];

看一下这个答案：how-to-get-the-image-from-uiwebview-in-ios。

Answer 3

您绝不应将drawRect:发送到视图（在您自己的super实施中使用drawRect:除外）。

您需要将图像视图的图像绘制到图形上下文中。试试这个：

- (void)savePhoto {
    UIGraphicsBeginImageContext(_selectedImageView.bounds.size);
    [_selectedImageView.image drawInRect:_selectedImageView.bounds];
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    UIImageWriteToSavedPhotosAlbum(image,
                                   self,
                                   @selector(savedPhotoImage:didFinishSavingWithError:contextInfo:),
                                   NULL);
}

以编程方式将图像保存到相机胶卷

3 个答案: