是否可以从uiwebview访问iphone的相机?我知道phonegap会这样做,但如何让它在没有手机功能的情况下工作?
感谢。
答案 0 :(得分:12)
您可以实现UIWebView Delegate并拦截任何尝试的页面加载。通过设置自定义URL,您可以将消息传递给可以启动摄像头的Objective C.要将数据发送回Web,我们可以启动新的加载(就像我在我的示例中所做的那样),或者在UIWebView上使用另一种方法传递一些javascript。
这是一个工作示例,我刚才写道:
#import "WebViewCamAppDelegate.h"
#import <UIKit/UIKit.h>
@interface uiwebviewcameraAppDelegate : NSObject <UIApplicationDelegate, UINavigationControllerDelegate, UIImagePickerControllerDelegate, UIWebViewDelegate> {
UIWindow *window;
UIViewController *viewController;
UIWebView *webView;
}
@property (nonatomic, retain) IBOutlet UIWindow *window;
@end
@implementation uiwebviewcameraAppDelegate
@synthesize window;
//This is the HTML we initially show in the WebView. Note the url "showcamera:" is one I
//invented with the intent to intercept it to show the camera.
static NSString *htmlString = @"<br><A href=\"showcamera:\">Show Camera</a>";
//Pretty Basic stuff. We set the UIWebView Delegate so we can intercept the call and set up //a ViewController so we can animate the UIImagePicker
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
viewController = [[UIViewController alloc] init];
webView = [[UIWebView alloc] initWithFrame:window.bounds];
[webView loadHTMLString:htmlString baseURL:nil];
webView.delegate = self;
[viewController.view addSubview:webView];
[window addSubview:viewController.view];
[window makeKeyAndVisible];
return YES;
}
//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 presentModalViewController:imagePicker animated:YES];
}
//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:@"showcamera"]) {
[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 dismissModalViewControllerAnimated:YES];
UIImage* image = [info objectForKey:UIImagePickerControllerOriginalImage];
NSData *imageData = UIImageJPEGRepresentation (image, 0.5);
[webView loadData:imageData MIMEType:@"image/jpeg" textEncodingName:@"UTF-8" baseURL:nil];
}
- (void)dealloc {
[viewController release];
[webView release];
[window release];
[super dealloc];
}
@end