最近项目上使用js调用OC，OC再次调用JS,再次在JS页面上面回显数据。
项目中使用的是WKWebview,加载网路的URL,其实就是使用WK加载出来的H5网页，在项目中用的是H5网页有个识别按钮，调起工程里面的OCR识别功能进行识别，OCR识别的数据信息放到一个数据字典里面，直接回传值即可，用OC执行远程的js数据进行回显数据,把json字符串传给他，前端用js进行回显数据字典。
js调用OC,以WKWebview为例
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc] init];
userContentController = [WKUserContentController new];
//提供一个扫描的js
[userContentController addScriptMessageHandler:self name:@"OCRScanAction"];
WKPreferences *preferences = [WKPreferences new];
preferences.javaScriptCanOpenWindowsAutomatically=YES;
// preferences.minimumFontSize = 40;
configuration.preferences =preferences;
configuration.userContentController = userContentController;
configuration.preferences.javaScriptEnabled = YES;
webview = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT) configuration:configuration];
webview.allowsBackForwardNavigationGestures = YES;//打开网页间的滑动返回
webview.allowsLinkPreview = YES; //允许预览链接
webview.navigationDelegate = self;
webview.scrollView.delegate = self;
webview.UIDelegate = self;
[webview sizeToFit];
[self.view addSubview:webview];
webview.scrollView.scrollEnabled = YES;
NSURL *url = [NSURL URLWithString:urlString];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[webview loadRequest:request];
//js调用OC代码段实现OCR功能
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{
NSLog(@"%@",message);
NSLog(@"body:%@",message.body);
if ([message.name isEqualToString:@"OCRScanAction"]) {
//调用OCRSDK
NSLog(@"message.body==%@",[message.body objectForKey:@"_clicktype"]);
NSString *ocrType = [message.body objectForKey:@"_clicktype"];
[[NSUserDefaults standardUserDefaults] setObject:ocrType forKey:@"_clicktype"];
NSLog(@"启动OCR");
ViewController *vc = [[ViewController alloc] init];
[self presentViewController:vc animated:YES completion:nil];
}
}
ViewController 是原生的控制器进行OCR扫描，把识别的信息传值过来 发送一个通知
[[NSNotificationCenter defaultCenter] postNotificationName:@"ocr" object:self userInfo:dict];//dict为数据字典
[self dismissViewControllerAnimated:YES completion:nil];
在H5网页控制器做监听
//设置OCR识别的监听
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(ocrBack:) name:@"ocr" object:nil];
#pragma mark---监听事件
- (void)ocrBack:(NSNotification *)notification{
NSDictionary *dict = notification.userInfo;
NSString *jsonStr = [self dictionaryToJson:dict];
NSString *jsStr = [NSString stringWithFormat:@"OCRScanActionCallback('%@')",jsonStr];
[webview evaluateJavaScript:jsStr completionHandler:^(id _Nullable result, NSError * _Nullable error) {
NSLog(@"%@----%@",result, error);
// NSLog(@"%@",result);
}];
}
#pragma mark --字典转换成字符串
- (NSString*)dictionaryToJson:(NSDictionary *)dic
{
NSError *parseError = nil;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dic options: error:&parseError];//注意这里options参数必须传0，否则回调回报语法错误
return [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
}
//就这里能显示出来回显的数据字典 把OCR扫描的结果传给H5页面上赋值进行回显。