html - 单击按钮时 UIWebView 打开相机和图像

Question

我目前正在将一个 webApp 包装成一个应用程序。在网络应用程序中有一个按钮，单击该按钮会自动询问您是否要转到存储图像的相机，选择后将为您上传图像。在手机浏览器的网络应用程序中，这按预期工作。

现在我已经将 webApp 包装在一个 UIWebView 中，这个功能不再有效。选择上述任一选项时，它实际上似乎关闭了 UIWebview。有谁知道通过 UIWebView 使其工作的程序是什么。

我必须给予许可吗？或者它还有更多功能，比如在单击按钮时检测 HTML 并从 UIWebView 处理它。

按钮上的 HTML 如下所示。

   <input type="file" required id="file" name="file" accept="image/*" multiple>

添加代码

WebViewController.h

 #import <UIKit/UIKit.h>

 @interface WebViewController : UIViewController <UIWebViewDelegate,UINavigationControllerDelegate, UIImagePickerControllerDelegate>
{
    UIViewController *viewController;
}

........

WebViewController.m

 #import "WebViewController.h"
 #import <AssetsLibrary/AssetsLibrary.h>
 #import "AppDelegate.h"
 @end
 @implementation WebViewController


 - (void)viewDidLoad
 {
      [super viewDidLoad];
      viewController = [[UIViewController alloc] init];   
      NSString *fullURL = self.mainURL; // get this from defualts - have removed code for this




NSURL *url = [NSURL URLWithString:fullURL];
NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
[_viewWeb loadRequest:requestObj];

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

[lib enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos usingBlock:^(ALAssetsGroup *group, BOOL *stop) {
    NSLog(@"%i",[group numberOfAssets]);
} failureBlock:^(NSError *error) {
    if (error.code == ALAssetsLibraryAccessUserDeniedError) {
        NSLog(@"user denied access, code: %i",error.code);
    }else{
        NSLog(@"Other error code: %i",error.code);
    }
}];
 }
  -(void)webViewDidStartLoad:(UIWebView *)viewWeb
 {
      [UIApplication sharedApplication].applicationIconBadgeNumber = 0;
 }
 - (void)webViewDidFinishLoad:(UIWebView *)viewWeb
 {

 }






 //Note: I check to make sure the camera is available.  If it is not (iPod touch or Simulator) I show the photo library instead.
 -(void) showCamera
 {
     UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
     if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
     {
         imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
     }
     else
     {
          imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
     }
     imagePicker.delegate = self;
     [viewController presentViewController:imagePicker animated:YES completion:nil];
 }

  //Here we intercept any time the webview tries to load a document.  When the user hits our "showcamera: url" we go to work.
  - (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:
  (UIWebViewNavigationType)navigationType
  {
        if ([request.URL.scheme isEqualToString:@"myApp"])
        {
            if ([request.URL.host isEqualToString:@"myFunction"])
            {
                [self showCamera];
            }
            return NO;
        }
        return YES;
   }

 //After the imagepicker has done it's thing, we pass the data back to the webview to be displayed.
 //If we wanted to be fancy here, we could have done this via Javascript so we could dynamically insert an image without reloading the page.
 - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    [viewController dismissViewControllerAnimated:YES completion:nil];
    UIImage* image = [info objectForKey:UIImagePickerControllerOriginalImage];
    NSData *imageData = UIImageJPEGRepresentation (image, 0.5);
    NSURL *tmp = [NSURL URLWithString:@"ignore"];
    [_viewWeb loadData:imageData MIMEType:@"image/jpeg" textEncodingName:@"UTF-8" baseURL:tmp];
   }
   @end

我删除了一些不相关的代码

Answer 1

我已经设法解决了这个问题，它可以追溯到在 iOS 8 中发现但仍未修复的错误。它与 UIWebView 的呈现方式有关。

添加此代码修复它。

 -(void)dismissViewControllerAnimated:(BOOL)flag completion:(void (^)(void))completion
 {
     if ( self.presentedViewController)
     {
         [super dismissViewControllerAnimated:flag completion:completion];
     }
 }

对于任何对此感到困惑或苦苦挣扎的人请注意，您不需要开始摆弄 UIImagePicker 或 UIWebView 委托(delegate)。您的 WebView 应负责打开相机库或相机。这是一个真正令人痛苦的问题，因此希望这可以帮助处于我位置的其他人。你还可以看到 THIS问题，因为这是我得到答案的地方。也感谢安德烈的帮助