iOS在UIWebView中通过Javascript调用摄像头、

直接上代码：

首先遵守代理

<HTSelectPhotoDelegate,UIActionSheetDelegate,UITextViewDelegate,UIWebViewDelegate, UINavigationControllerDelegate, UIImagePickerControllerDelegate>
{
    NSString *callback;
}

- (void)viewDidLoad{
    
    [super viewDidLoad];
    
    self.webView = [[UIWebView alloc]initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT)];
    [self.view addSubview:self.webView];
    self.webView.delegate = self;
    NSString *filePath = [[NSBundle mainBundle] pathForResource:@"camera" ofType:@"html"];
    NSString *fileContent = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:nil];
    [self.webView loadHTMLString:fileContent baseURL:nil];
}

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType
{
    
    DDLog(@"URL==%@",[request URL]);
    
    NSString *requestString = [[request URL] absoluteString];
    NSString *protocol = @"js-call://";
    
    if ([requestString hasPrefix:protocol]) {
        
        NSString *requestContent = [requestString substringFromIndex:[protocol length]];
        NSArray *vals = [requestContent componentsSeparatedByString:@"/"];
        DDLog(@"vals==%@",vals);
        if ([[vals objectAtIndex:0] isEqualToString:@"camera"]) {
            callback = [vals objectAtIndex:1];
            [self doAction:UIImagePickerControllerSourceTypeCamera];
        } else if([[vals objectAtIndex:0] isEqualToString:@"photolibrary"]) {
            callback = [vals objectAtIndex:1];
            [self doAction:UIImagePickerControllerSourceTypePhotoLibrary];
        } else if([[vals objectAtIndex:0] isEqualToString:@"album"]) {
            callback = [vals objectAtIndex:1];
            [self doAction:UIImagePickerControllerSourceTypeSavedPhotosAlbum];
        }else{
            [webView stringByEvaluatingJavaScriptFromString:@"alert('未定义/lwme.cnblogs.com');"];
        }
        return NO;
    }
    return YES;
}

- (void)doAction:(UIImagePickerControllerSourceType)sourceType
{
    UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
    imagePicker.delegate = self;
    if ([UIImagePickerController isSourceTypeAvailable:sourceType]) {
        imagePicker.sourceType = sourceType;
    } else {
        UIAlertView *av = [[UIAlertView alloc] initWithTitle:@"照片获取失败" message:@"没有可用的照片来源" delegate:nil cancelButtonTitle:@"确定" otherButtonTitles:nil, nil];
        [av show];
        return;
    }
    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {
        UIPopoverController *popover = [[UIPopoverController alloc] initWithContentViewController:imagePicker];
        [popover presentPopoverFromRect:CGRectMake(self.view.bounds.size.width / 2, self.view.bounds.size.height / 3, 10, 10) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
    } else {
        [self presentViewController:imagePicker animated:YES completion:nil];
//        [self presentModalViewController:imagePicker animated:YES];
    }
}

-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
{
    if ([[info objectForKey:UIImagePickerControllerMediaType] isEqualToString:@"public.image"]){
        
        UIImage *originalImage = [info objectForKey:UIImagePickerControllerOriginalImage];
        
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"正在处理图片..." message:nil
                                                    delegate:self
                                           cancelButtonTitle:nil
                                           otherButtonTitles:nil, nil];
        [alertView show];

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0), ^{
            
//            NSString *base64 = [UIImagePNGRepresentation(originalImage) base64Encoding];
            NSData *dataIMG = UIImageJPEGRepresentation(originalImage, 0.4);
            NSString *base64=[dataIMG base64EncodedStringWithOptions:NSUTF8StringEncoding];

            [self performSelectorOnMainThread:@selector(doCallback:) withObject:base64 waitUntilDone:NO];
            [alertView dismissWithClickedButtonIndex:0 animated:YES];
            
        });
    }
    
    [picker dismissViewControllerAnimated:YES completion:nil];
//    [picker dismissModalViewControllerAnimated:YES];
}

- (void)doCallback:(NSString *)data
{
    [self.webView stringByEvaluatingJavaScriptFromString:[NSString stringWithFormat:@"%@('%@');", callback, data]];
}

附上camera.html源码如下：

<script>
    function cameraCallback(imageData) {
        var img = createImageWithBase64(imageData);
        document.getElementById("cameraWrapper").appendChild(img);
    }
    function photolibraryCallback(imageData) {
        var img = createImageWithBase64(imageData);
        document.getElementById("photolibraryWrapper").appendChild(img);
    }
    function albumCallback(imageData) {
        var img = createImageWithBase64(imageData);
        document.getElementById("albumWrapper").appendChild(img);
    }
    function createImageWithBase64(imageData) {
        var img = new Image();
        img.src = "data:image/jpeg;base64," + imageData;
        img.style.width = "50px";
        img.style.height = "50px";
        return img;
    }
</script>
<p style="text-align:center;padding:20px;">
    <a href="js-call://camera/cameraCallback">拍照</a>  
    <a href="js-call://photolibrary/photolibraryCallback">图库</a>  
    <a href="js-call://album/albumCallback">相册</a>
</p>

<fieldset>
    <legend>拍照</legend>
    <div id="cameraWrapper">
    </div>
</fieldset>

<fieldset>
    <legend>图库</legend>
    <div id="photolibraryWrapper">
    </div>
</fieldset>

<fieldset>
    <legend>相册</legend>
    <div id="albumWrapper">
    </div>
</fieldset>

详细示例，在github可以下载
https://github.com/corminlu/UIWebViewCallCamera