edison0951 / easyjswebview

Enable adding Javascript Interface to UIWebView like Android WebView

EasyJSWebView - much simpler JS X Obj-C interaction

This repository was forked from https://github.com/dukeland/EasyJSWebView

Since the original version breaks on redirects in the webview, I changed it to work after every page load (webViewDidFinishLoad).

Because of this modification, if you try to call the bridge (e.g. MyJSTest.test() from the sample), without waiting for the page to load, it will NOT work.

Try this instead:

setTimeout(function() { MyJSTest.test() }, 1);

###Introduction You are using UIWebView in your iOS app and you want to do some communications between the Javascript inside the WebView and Objective-C. How would you do it?

To run Javascript in Objective-C, you can use the – stringByEvaluatingJavaScriptFromString: method. To run Objective-C method, well it is a little bit tricky, you need to implement the UIWebViewDelegate and the shouldStartLoadWithRequest method.

Do you know how to do this in Android? You simply need to create a class and pass an instance to the WebView through addJavascriptInterface(Object object, String name).

EasyJSWebView is a library that allows you to do the same in Objective-C. Download it and try. I promise. It is much simpler to do the job!!!

You may find the sample project here.

###Some code to demonstrate So basically what you need to do is create a class like this.

@interface MyJSInterface : NSObject

- (void) test;
- (void) testWithParam: (NSString*) param;
- (void) testWithTwoParam: (NSString*) param AndParam2: (NSString*) param2;

- (NSString*) testWithRet;

@end

Then add the interface to your UIWebView.

MyJSInterface* interface = [MyJSInterface new];
[self.myWebView addJavascriptInterfaces:interface WithName:@"MyJSTest"];
[interface release];

In Javascript, you can call the Objective-C methods by this simple code.

MyJSTest.test();
MyJSTest.testWithParam("ha:ha");
MyJSTest.testWithTwoParamAndParam2("haha1", "haha2");

var str = MyJSTest.testWithRet();

Just that simple!!! EasyJSWebView will help you do the injection. And you do not even need to use async-style writing to get the return value!!!

But of course, sometimes we may need to use the async-style code. It is also supported. You can even get the return value from the callback function.

- (void) testWithFuncParam: (EasyJSDataFunction*) param{
  NSLog(@"test with func");
	
	NSString* ret = [param executeWithParam:@"blabla:\"bla"];
	
	NSLog(@"Return value from callback: %@", ret);
}

And in Javascript,

MyJSTest.testWithFuncParam(function (data){
	alert(data); //data would be blabla:"bla
	return "some data";
});

Simple, huh!?

Try it now!!!

###Some simple facts

• NSInvocation does not live peacefully with ARC. This library is thus a non-ARC library.
• It supports only NSString* for message passing now.
• We are Dukeland from Hong Kong! A group of IT-holic guys