DSBridge for Android

Modern cross-platform JavaScript bridge, through which you can invoke each other's functions synchronously or asynchronously between JavaScript and native applications.

Chinese documentation 中文文档
DSBridge-IOS：https://github.com/wendux/DSBridge-IOS
Tencent x5 webcore support

Notice

DSBridge v3.0 is a milestone version. Compared with v2.0, we have made a lot of changes. Note that v3.0 is incompatible with v2.0, but v2.0 will continue to maintain. If you are a new user, use >=v3.0.

DSBridge v3.0.0 change list

Features

1. The three ends of Android, IOS and Javascript are easy to use, light and powerful, secure and strong
2. Both synchronous and asynchronous calls are supported
3. Support API Object, which centrally implements APIs in a Java Class or a Javascript object
4. Support API namespace
5. Support debug mode
6. Support the test of whether API exists
7. Support Progress Callback: one call, multiple returns
8. Support event listener for Javascript to close the page
9. Support Modal and Modeless popup box for javascript
10. Support the X5 webcore of Tencent

Installation

1. Add the JitPack repository to your build file

   allprojects {
     repositories {
      ...
      maven { url 'https://jitpack.io' }
     }
   }

2. Add the dependency

   dependencies {
    //compile 'com.github.wendux:DSBridge-Android:3.0-SNAPSHOT'
    //support the x5 browser core of Tencent
    //compile 'com.github.wendux:DSBridge-Android:x5-3.0-SNAPSHOT'
   }

Examples

See the wendu.jsbdemo/ package. run the app project and to see it in action.

To use dsBridge in your own project:

Usage

1. Implement APIs in a Java class

   public class JsApi{
       //for synchronous invocation
       @JavascriptInterface
       public String testSyn(Object msg)  {
           return msg + "［syn call］";
       }
   
       //for asynchronous invocation
       @JavascriptInterface
       public void testAsyn(Object msg, CompletionHandler handler) {
           handler.complete(msg+" [ asyn call]");
       }
   }

   For security reason, Java APIs must be with "@JavascriptInterface" annotation .

2. Add API object to DWebView .

   import wendu.dsbridge.DWebView
   ...
   DWebView dwebView= (DWebView) findViewById(R.id.dwebview);
   dwebView.addJavascriptObject(new JsApi(), null);

3. Call Native (Java/Object-c/swift) API in Javascript, and register javascript API.

   • Init dsBridge

     //cdn
     //<script src="https://unpkg.com/[email protected]/dist/dsbridge.js"> </script>
     //npm
     //npm install [email protected]
     var dsBridge=require("dsbridge")

   • Call Native API and register a javascript API for Native invocation.

     //Call synchronously 
     var str=dsBridge.call("testSyn","testSyn");
     
     //Call asynchronously
     dsBridge.call("testAsyn","testAsyn", function (v) {
       alert(v);
     })
     
     //Register javascript API for Native
      dsBridge.register('addValue',function(l,r){
          return l+r;
      })

4. Call Javascript API in java

   dwebView.callHandler("addValue",new Object[]{3,4},new OnReturnValue<Integer>(){
        @Override
        public void onValue(Integer retValue) {
           Log.d("jsbridge","call succeed,return value is "+retValue);
        }
   });

Java API signature

In order to be compatible with IOS , we make the following convention on Java API signature:

1. For synchronous API.

   public any handler(Object msg)

   The argument type must be Object and must be declared even if not need)，and the type of return value is not limited.

2. For asynchronous API.

   public void handler(Object arg, CompletionHandler handler)

Namespace

Namespaces can help you better manage your APIs, which is very useful in hybrid applications, because these applications have a large number of APIs. DSBridge (>= v3.0.0) allows you to classify API with namespace. And the namespace can be multilevel, between different levels with '.' division.

Debug mode

In debug mode, some errors will be prompted by a popup dialog , and the exception caused by the native APIs will not be captured to expose problems. We recommend that the debug mode be opened at the development stage. You can open debug mode :

DWebView.setWebContentsDebuggingEnabled(true)

Progress Callback

Normally, when a API is called to end, it returns a result, which corresponds one by one. But sometimes a call need to repeatedly return multipule times, Suppose that on the Native side, there is a API to download the file, in the process of downloading, it will send the progress information to Javascript many times, then Javascript will display the progress information on the H5 page. Oh...You will find it is difficult to achieve this function. Fortunately, DSBridge supports Progress Callback. You can be very simple and convenient to implement a call that needs to be returned many times. Here's an example of a countdown：

In Java

@JavascriptInterface
public void callProgress(Object args, final CompletionHandler<Integer> handler) {
    new CountDownTimer(11000, 1000) {
        int i=10;
        @Override
        public void onTick(long millisUntilFinished) {
            //setProgressData can be called many times util complete be called.
            handler.setProgressData((i--));
        }
        @Override
        public void onFinish() {
           //complete the js invocation with data; 
           //handler will be invalid when complete is called
            handler.complete(0);
        }
    }.start();
}

In Javascript

dsBridge.call("callProgress", function (value) {
    document.getElementById("progress").innerText = value
})

For the complete sample code, please refer to the demo project.

Javascript popup box

For Javascript popup box functions (alert/confirm/prompt), DSBridge has implemented them all by default, if you want to custom them, override the corresponding callback in WebChromeClient . The default dialog box implemented by DSBridge is modal. This will block the UI thread. If you need modeless, please refer to dwebview.disableJavascriptDialogBlock (bool disable).

Security

Before Android 4.2 (API 17), webview.addJavascriptInterface has security vulnerabilities, and DSBridge doesn't use it under 4.2 of the devices. Meanwhile, in order to prevent Javascript from calling unauthorized native functions, all Java APIs must be annotated with "@JavascriptInterface" , so you can use DSBridge safely.

DWebView

In DWebview, the following functions will execute in main thread automatically, you need not to switch thread by yourself.

void loadUrl( String url) 
void loadUrl(final String url, Map<String, String> additionalHttpHeaders)
void evaluateJavascript(String script) 

API Reference

Java API

In Java, the object that implements the javascript interfaces is called Java API object.

dwebview.addJavascriptObject(Object object, String namespace)

Add the Java API object with supplied namespace into DWebView. The javascript can then call Java APIs with bridge.call("namespace.api",...).

If the namespace is empty, the Java API object have no namespace. The javascript can call Java APIs with bridge.call("api",...).

Example:

In Java

public class JsEchoApi {
    @JavascriptInterface
    public Object syn(Object args) throws JSONException {
        return  args;
    }

    @JavascriptInterface
    public void asyn(Object args,CompletionHandler handler){
        handler.complete(args);
    }
}
//namespace is "echo"
dwebView.addJavascriptObject(new JsEchoApi(),"echo");

In Javascript

// call echo.syn
var ret=dsBridge.call("echo.syn",{msg:" I am echoSyn call", tag:1})
alert(JSON.stringify(ret))  
// call echo.asyn
dsBridge.call("echo.asyn",{msg:" I am echoAsyn call",tag:2},function (ret) {
      alert(JSON.stringify(ret));
})

dwebview.removeJavascriptObject(String namespace)

Remove the Java API object with supplied namespace.

dwebview.callHandler(String handlerName, Object[] args)

dwebview.callHandler(String handlerName, OnReturnValue handler)

dwebview.callHandler(String handlerName, Object[] args,OnReturnValue handler)

Call the javascript API. If a handler is given, the javascript handler can respond. the handlerName can contain the namespace. The handler will be called in main thread.

Example:

dWebView.callHandler("append",new Object[]{"I","love","you"},new OnReturnValue<String>((){
    @Override
    public void onValue(String retValue) {
        Log.d("jsbridge","call succeed, append string is: "+retValue);
    }
});
// call with namespace 'syn', More details to see the Demo project                    
dWebView.callHandler("syn.getInfo", new OnReturnValue<JSONObject>() {
    @Override
    public void onValue(JSONObject retValue) {
      showToast(retValue);
    }
});

dwebview.disableJavascriptDialogBlock(bool disable)

BE CAREFUL to use. if you call any of the javascript popup box functions (alert, confirm, and prompt), the app will hang, and the javascript execution flow will be blocked. if you don't want to block the javascript execution flow, call this method, the popup box functions will return immediately( confirm return true, and the prompt return empty string).

Example:

dwebview.disableJavascriptDialogBlock(true);

if you want to enable the block, just calling this method with the argument value false .

dwebview.setJavascriptCloseWindowListener(JavascriptCloseWindowListener listener)

DWebView calls listener.onClose when Javascript calls window.close. the default handler is closing the current active activity. you can provide a listener to add your hanlder .

Example:

dwebview.setJavascriptCloseWindowListener(new DWebView.JavascriptCloseWindowListener() {
    @Override
    public boolean onClose() {
        Log.d("jsbridge","window.close is called in Javascript");
        //If return false,the default handler will be prevented. 
        return false;
    }
});

dwebview.hasJavascriptMethod(String handlerName, OnReturnValue<Boolean> existCallback)

Test whether the handler exist in javascript.

Example:

 dWebView.hasJavascriptMethod("addValue", new OnReturnValue<Boolean>() {
    @Override
    public void onValue(Boolean retValue) {
     showToast(retValue);
    }
 });

DWebView.setWebContentsDebuggingEnabled(boolean enabled)

Set debug mode. if in debug mode, some errors will be prompted by a popup dialog , and the exception caused by the native APIs will not be captured to expose problems. We recommend that the debug mode be opened at the development stage.

Javascript API

dsBridge

"dsBridge" is accessed after dsBridge Initialization .

dsBridge.call(method,[arg,callback])

Call Java api synchronously and asynchronously。

method: Java API name， can contain the namespace。

arg: argument, Only one allowed, if you expect multiple parameters, you can pass them with a json object.

callback(String returnValue): callback to handle the result. only asynchronous invocation required.

dsBridge.register(methodName|namespace,function|synApiObject)

dsBridge.registerAsyn(methodName|namespace,function|asyApiObject)

Register javascript synchronous and asynchronous API for Native invocation. There are two types of invocation

1. Just register a method. For example:

   In Javascript

   dsBridge.register('addValue',function(l,r){
        return l+r;
   })
   dsBridge.registerAsyn('append',function(arg1,arg2,arg3,responseCallback){
        responseCallback(arg1+" "+arg2+" "+arg3);
   })

   In Java

   webView.callHandler("addValue",new Object[]{1,6},new OnReturnValue(){
     @Override
     public void onValue(String retValue) {
       Log.d("jsbridge","call succeed,return value is: "+retValue);
     }
   });
   
    webView.callHandler("append",new Object[]{"I","love","you"},new OnReturnValue(){
      @Override
      public void onValue(String retValue) {
        Log.d("jsbridge","call succeed, append string is: "+retValue);
      }
    });

   ​

2. Register a Javascript API object with supplied namespace. For example:

   In Javascript

   //namespace test for synchronous
   dsBridge.register("test",{
     tag:"test",
     test1:function(){
   	return this.tag+"1"
     },
     test2:function(){
   	return this.tag+"2"
     }
   })
     
   //namespace test1 for asynchronous calls  
   dsBridge.registerAsyn("test1",{
     tag:"test1",
     test1:function(responseCallback){
   	return responseCallback(this.tag+"1")
     },
     test2:function(responseCallback){
   	return responseCallback(this.tag+"2")
     }
   })

   Because JavaScript does not support function overloading, it is not possible to define asynchronous function and sync function of the same name。

   In Java

   webView.callHandler("test.test1",new OnReturnValue<String>(){
       @Override
       public void onValue(String retValue) {
           Log.d("jsbridge","Namespace test.test1: "+retValue);
       }
   });
   
   webView.callHandler("test1.test1",new OnReturnValue<String>(){
       @Override
       public void onValue(String retValue) {
           Log.d("jsbridge","Namespace test.test1: "+retValue);
       }
   });

dsBridge.hasNativeMethod(handlerName,[type])

Test whether the handler exist in Java, the handlerName can contain the namespace.

type: optional["all"|"syn"|"asyn" ], default is "all".

dsBridge.hasNativeMethod('testAsyn') 
//test namespace method
dsBridge.hasNativeMethod('test.testAsyn')
// test if exist a asynchronous function that named "testSyn"
dsBridge.hasNativeMethod('testSyn','asyn') //false

dsBridge.disableJavascriptDialogBlock(disable)

Calling dsBridge.disableJavascriptDialogBlock(...) has the same effect as calling dwebview.disableJavascriptDialogBlock(...) in Java.

Example:

//disable
dsBridge.disableJavascriptDialogBlock()
//enable
dsBridge.disableJavascriptDialogBlock(false)

Work with fly.js

As we all know, In browser, AJax request are restricted by same-origin policy, so the request cannot be initiated across the domain. However, Fly.js supports forwarding the http request to Native through any Javascript bridge, And fly.js has already provide the dsBridge adapter.Because the Native side has no the same-origin policy restriction, fly.js can request any resource from any domain.

Another typical scene is in the hybrid App, Fly.js will forward all requests to Native, then, the unified request management, cookie management, certificate verification, request filtering and so on are carried out on Native.

For the complete sample code, please refer to the demo project.

Finally

If you like DSBridge, please star to let more people know it , Thank you !