H5 and native interaction is a very common requirement, now introduce the basic interaction method
Android side:
1. The main implementation method of H5 calling Android native methods is to inject a custom js object into the web through the addJavascriptInterface method of WebView to implement js calling Android methods.
1. H5 calls the Android method
1.1. For example: the H5 end calls the finishActivity method on the Android end:
window.android.finishActivity('Send to android1')
1.2. Android injects an object (android) into WebView:
@JavascriptInterface public void finishActivity(String value) {
Log.e("Native method invoked by js=",value);
finish();
}
1.3, webview code configuration:
2. Android calls the H5 method
2.1. H5 needs to mount events in the window and expose them to mobile calls:
window.setAuthentication = this.setAuthentication
//specific method
setAuthentication(param) {
this.roomTotal = JSON.stringify(param)
return '...authentication information....'
}
2.2. Call the js method through the evaluateJavascript method of WebView: 
2.3, Android 4.4 and above call evaluateJavascript to implement calling the js method, and at the same time can obtain the data returned by the web page. webview.evaluateJavascript(javascript: method name (parameter),
new ValueCallback{
public void onReciveValue(String value){}
})
2. The parameter is a string in json format, and the web page will receive a json object
IOS side:
1. js calls iOS native methods JS calls iOS native methods through the WKScriptMessageHandler protocol provided by WkwebView.
The H5 side calls the nativeMethod method on the iOS side: window.webkit.messageHandlers.nativeMethod.postMessage('');
iOS native registration method
nativeMethod： [config.userContentController addScriptMessageHandler:self name:@"nativeMethod"];
When js calls the method registered by iOS, iOS will use the proxy method of WKScriptMessageHandler:
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message
2. iOS calls the js method
Call the js method through evaluateJavaScript of WkWebView:
NSString *promptCode = [NSString stringWithFormat:@"%@()", @"nativeCalljs0"]; [self.wkWebView evaluateJavaScript:promptCode completionHandler:^(id _Nullable result, NSError * _Nullable error) {
//result can receive the return value of the js method
NSLog(@"%@",result);
}];
Because iOS and Android have different calling methods from H5, we need to judge the embedded platform in advance. The complete code is as follows:
