android js 互相调用 第二版
-
支持js匿名函数接收
-
支持js json对象接收
-
支持js函数返回值获取
-
通过注解注入js方法
-
优化第一版的反射注入方式，采用注解处理器编译时生成注入代码,提高运行效率
-
加入简单的 webview 预加载功能
实现原理
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通过注解处理器实现js代码自动生成
-
创建WebViewChromeClient重写 onProgress方法当进度大于30%的时候执行js代码注入,js代码必须注入成功才能调用
js代码生成逻辑
/**
* 注解处理器
*/
@AutoService(Processor.class) public class InjectProcessor extends AbstractProcessor {
/**
* 文件相关的辅助类
*/
private Filer mFiler;
/**
* 元素相关的辅助类
*/
private Elements mElementUtils;
/**
* 日志相关的辅助类
*/
private Messager mMessager;
//返回注解处理器可处理的注解操作
//@Override public Set<String> getSupportedOptions() {
// return getSupportedAnnotationTypes();
//}
@Override public SourceVersion getSupportedSourceVersion() {
return SourceVersion.RELEASE_7;
}
//得到注解处理器可以支持的注解类型
@Override public Set<String> getSupportedAnnotationTypes() {
HashSet<String> objects = new HashSet<>();
objects.add(JsInject.class.getName());
return objects;
}
//执行一些初始化逻辑
@Override public synchronized void init(ProcessingEnvironment processingEnv) {
super.init(processingEnv);
mFiler = processingEnv.getFiler();
mElementUtils = processingEnv.getElementUtils();
mMessager = processingEnv.getMessager();
}
//核心方法，扫描，解析并处理自定义注解，生成***.java文件
@Override public boolean process(Set<? extends TypeElement> annotations,
RoundEnvironment roundEnv) {
try {
processImpl(roundEnv);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return false;
}
private void processImpl(RoundEnvironment roundEnv) throws ClassNotFoundException, IOException {
// 获取被 JsInject 标记的元素
Set<? extends Element> elementsAnnotatedWith =
roundEnv.getElementsAnnotatedWith(JsInject.class);
Iterator<? extends Element> iterator = elementsAnnotatedWith.iterator();
//创建模板代码
String objectJs = "if(typeof(window.%s)=='undefined'){ window.%s = {";
String methodJs = "%s:function(){"
+ " return EasyJS.call('%s', '%s', Array.prototype.slice.call(arguments));},";
final StringBuilder objectSb = new StringBuilder();
Map<String, String> map = new HashMap<>();
while (iterator.hasNext()) {
Element next = iterator.next();
JsInject jsInject = next.getAnnotation(JsInject.class);
//String classType = next.asType().toString();
//error(next.getEnclosingElement() + "-----" + next.getKind() + "-----" + next.getSimpleName()
// +"----------"+next.getEnclosedElements()+"------"+next.asType().toString()+"--------",
// next);
// 获取 被JsInject 标记的 class ，并判断 当前类是否继承于 com.liwg.jsbridge.library.JsPlugin
TypeElement typeElement = (TypeElement) next;
if (!typeElement.getSuperclass().toString().equals("com.liwg.jsbridge.library.JsPlugin")) {
error("cover JsInject note class must extends JsPlugin", next);
return;
}
String objectName = jsInject.value();
if (objectName == null || objectName.length() < 1) {
objectName = typeElement.getSimpleName().toString();
}
map.put(objectName, String.format("new %s()", typeElement.getQualifiedName().toString()));
objectSb.append(String.format(objectJs, objectName, objectName));
final StringBuilder methodSb = new StringBuilder();
// 获取方法列表
List<? extends Element> methodElements = next.getEnclosedElements();
for (int i = 0; i < methodElements.size(); i++) {
Element element = methodElements.get(i);
if(!(element instanceof ExecutableElement))
continue;
ExecutableElement method = (ExecutableElement) element;
String methodName = method.getSimpleName().toString();
// 存在一个 <init>方法，过滤掉
if (methodName.contains("<")) continue;
if (!method.getModifiers().contains(Modifier.PUBLIC)) {
//必须是public 修饰的方法
continue;
}
// 过滤掉 JsInject 注解 声明需要过滤的方法
if (!filterMethod(jsInject.filter(), methodName)) {
//不需要过滤此方法
methodSb.append(String.format(methodJs, methodName, objectName, methodName));
}
}
if (methodSb.length() > 0) methodSb.deleteCharAt(methodSb.length() - 1);
objectSb.append(methodSb);
objectSb.append("}}");
}
objectSb.append("if(window.EasyJS&&window.EasyJS.injectFlag==0){if(JSBridgeReady){JSBridgeReady();window.EasyJS.injectFlag=1}}");
String jsCode = objectSb.toString();
// 创建 java 源文件
JavaFileObject sourceFile = mFiler.createSourceFile("com.liwg.jsbridge.library.JSBridge");
Writer writer = null;
try {
writer = sourceFile.openWriter();
writer.write("package com.liwg.jsbridge.library;
");
writer.write("final class JSBridge implements com.liwg.jsbridge.library.IJSBridge{
");
writer.write(" public static final JSBridge INSTANCE = new JSBridge();
");
writer.write(" public java.util.Map<String,Object> map = new java.util.HashMap<>();
");
writer.write(" private JSBridge(){
");
for (Map.Entry<String, String> entry : map.entrySet()) {
writer.write(String.format(" map.put("%s",%s);
", entry.getKey(), entry.getValue()));
}
writer.write(" }
");
writer.write(" public static final JSBridge get(){
");
writer.write(" return INSTANCE;
");
writer.write(" }
");
writer.write(" public String getJsCode(){
");
writer.write(" return "" + jsCode + "";
");
writer.write(" }
");
writer.write(
" /**注册对象， 被@JsPlugin注解标记的对象会自动注入，并调用空参的构造函数，
如果需要重写构造，需保留空参的构造，并调用此方法注册
*/
");
writer.write(" public void register(String name,Object obj){
");
writer.write(" map.put(name,obj);
");
writer.write(" }
");
writer.write(" public Object queryJavaObject(String name){
");
writer.write(" return map.get(name);
");
writer.write(" }
");
/* writer.write(" public void callJsReady(com.liwg.jsbridge.library.BridgeWebView webview){
");
writer.write(" webview.callJsMethod("JSBridgeReady()");
");
writer.write(" }
");*/
writer.write(" }
");
} catch (Exception e) {
error(e.getLocalizedMessage(),roundEnv.getRootElements().iterator().next());
} finally {
writer.close();
}
}
private boolean filterMethod(String[] filter, String methodName) {
int length = filter == null ? 0 : filter.length;
for (int i = 0; i < length; i++) {
if (filter[i].equals(methodName)) {
return true;
}
}
return false;
}
void error(CharSequence msg, Element element) {
mMessager.printMessage(Diagnostic.Kind.WARNING, msg, element);
}
}
生成的代码
final class JSBridge implements com.liwg.jsbridge.library.IJSBridge{
public static final JSBridge INSTANCE = new JSBridge();
public java.util.Map<String,Object> map = new java.util.HashMap<>();
private JSBridge(){
//生成 注入 js对象名和java对象的映射
map.put("AB",new com.src.wugang.jsbridge.MainActivity.AB());
map.put("Plugin",new com.src.wugang.jsbridge.A());
}
public static final JSBridge get(){
return INSTANCE;
}
public String getJsCode(){
return "if(typeof(window.Plugin)=='undefined'){ window.Plugin = {test:function(){ return EasyJS.call('Plugin', 'test', Array.prototype.slice.call(arguments));},test1:function(){ return EasyJS.call('Plugin', 'test1', Array.prototype.slice.call(arguments));}}}if(typeof(window.AB)=='undefined'){ window.AB = {test:function(){ return EasyJS.call('AB', 'test', Array.prototype.slice.call(arguments));},test1:function(){ return EasyJS.call('AB', 'test1', Array.prototype.slice.call(arguments));},test2:function(){ return EasyJS.call('AB', 'test2', Array.prototype.slice.call(arguments));}}}if(window.EasyJS&&window.EasyJS.injectFlag==0){if(JSBridgeReady){JSBridgeReady();window.EasyJS.injectFlag=1}}";
}
/**注册对象， 被@JsPlugin注解标记的对象会自动注入，并调用空参的构造函数，
如果需要重写构造，需保留空参的构造，并调用此方法注册
*/
public void register(String name,Object obj){
map.put(name,obj);
}
public Object queryJavaObject(String name){
return map.get(name);
}
}
使用方式
<com.wugang.jsbridge.library.BridgeWebView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/web_view"/>
Activity
- 注入的插件对象必须实现JsPlugin接口,所有需要注入的对象必须继承JsPlugin这个类并且 加上 @JsInject 注解标记
- 被 @JsInject 标记的类会被自动注入，并调用空参的构造创建对象，如果有自定义构造 可以使用 webView.getJsBridge().register()
- 如果该类中的方法不希望被注入可以 使用 @JsInject 注解上的 filter参数过滤掉
public class MainActivity extends AppCompatActivity {
@Override protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
PreLoadManager.get(this).preload("http://www.baidu.com", "http://www.youku.com");
BridgeWebView webView = (BridgeWebView) findViewById(R.id.web_view);
webView.getJsBridge().register("AB",new AB(this));
webView.loadUrl("file:///android_asset/test.html");
WebView.setWebContentsDebuggingEnabled(true);
}
@JsInject public static class AB extends JsPlugin {
private Context context;
public AB() {
}
public AB(Context context) {
this.context = context;
}
public void test(String s, JSFunction jsFunction) {
Toast.makeText(context, "js调用我", 1).show();
jsFunction.execute("test execute " + s);
}
public void test1() {
Log.e("-------", "test1: ");
}
public void test2() {
Log.e("-------", "test2: ");
}
}
}
HTML&JS代码
<html>
<script>
// 推荐使用方式，否则直接调用将无法调用到 原生方法
window.JSBridgeReady=function(){
console.log("---window EasyJSReady---")
AB.test2();
AB.test("call test",function(ret){
console.log(ret)
})
}
</script>
<script src="test.js"></script>
<body>
<button onclick="javascript:location.reload()">refresh</button>
</body>
</html>
网页预加载
//预加载，推荐在Application中调用
PreLoadManager.get(this).preload("http://www.baidu.com", "http://www.youku.com");
Activity 中使用
public class PreLoadActivity extends AppCompatActivity {
@Override protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
BridgeWebView webView = PreLoadManager.get(this).getWebView();
setContentView(webView);
webView.setWebViewClient(new WebViewClient(){
@Override public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
if(request.hasGesture()){
Intent intent = new Intent(PreLoadActivity.this,PreLoadActivity.class);
intent.putExtra("url",request.getUrl());
startActivity(intent);
return true;
}
return super.shouldOverrideUrlLoading(view, request);
}
});
webView.loadUrl(getIntent().getStringExtra("url"));
}
}
项目结构图
参考项目https://github.com/lwugang/safe-java-js-webview-bridge
参考项目https://github.com/dukeland/EasyJSWebView
android js 互相调用
注：本文著作权归作者，由demo大师代发，拒绝转载，转载需要作者授权