android js 互相調用 第二版
-
支持js匿名函數接收
-
支持js json對象接收
-
支持js函數返回值獲取
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通過注解注入js方法
-
優化第一版的反射注入方式，采用注解處理器編譯時生成注入代碼,提高運行效率
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加入簡單的 webview 預加載功能
實現原理
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通過注解處理器實現js代碼自動生成
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創建WebViewChromeClient重寫 onProgress方法當進度大於30%的時候執行js代碼注入,js代碼必須注入成功才能調用
js代碼生成邏輯
/**
* 注解處理器
*/
@AutoService(Processor.class) public class InjectProcessor extends AbstractProcessor {
/**
* 文件相關的輔助類
*/
private Filer mFiler;
/**
* 元素相關的輔助類
*/
private Elements mElementUtils;
/**
* 日志相關的輔助類
*/
private Messager mMessager;
//返回注解處理器可處理的注解操作
//@Override public Set<String> getSupportedOptions() {
// return getSupportedAnnotationTypes();
//}
@Override public SourceVersion getSupportedSourceVersion() {
return SourceVersion.RELEASE_7;
}
//得到注解處理器可以支持的注解類型
@Override public Set<String> getSupportedAnnotationTypes() {
HashSet<String> objects = new HashSet<>();
objects.add(JsInject.class.getName());
return objects;
}
//執行一些初始化邏輯
@Override public synchronized void init(ProcessingEnvironment processingEnv) {
super.init(processingEnv);
mFiler = processingEnv.getFiler();
mElementUtils = processingEnv.getElementUtils();
mMessager = processingEnv.getMessager();
}
//核心方法，掃描，解析並處理自定義注解，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 {
// 獲取被 JsInject 標記的元素
Set<? extends Element> elementsAnnotatedWith =
roundEnv.getElementsAnnotatedWith(JsInject.class);
Iterator<? extends Element> iterator = elementsAnnotatedWith.iterator();
//創建模板代碼
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);
// 獲取 被JsInject 標記的 class ，並判斷 當前類是否繼承於 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();
// 獲取方法列表
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();
// 存在一個 <init>方法，過濾掉
if (methodName.contains("<")) continue;
if (!method.getModifiers().contains(Modifier.PUBLIC)) {
//必須是public 修飾的方法
continue;
}
// 過濾掉 JsInject 注解 聲明需要過濾的方法
if (!filterMethod(jsInject.filter(), methodName)) {
//不需要過濾此方法
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();
// 創建 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;\n\n");
writer.write("final class JSBridge implements com.liwg.jsbridge.library.IJSBridge{\n");
writer.write(" public static final JSBridge INSTANCE = new JSBridge();\n");
writer.write(" public java.util.Map<String,Object> map = new java.util.HashMap<>();\n");
writer.write(" private JSBridge(){\n");
for (Map.Entry<String, String> entry : map.entrySet()) {
writer.write(String.format(" map.put(\"%s\",%s); \n", entry.getKey(), entry.getValue()));
}
writer.write(" }\n");
writer.write(" public static final JSBridge get(){\n");
writer.write(" return INSTANCE;\n");
writer.write(" }\n");
writer.write(" public String getJsCode(){\n");
writer.write(" return \"" + jsCode + "\";\n");
writer.write(" }\n");
writer.write(
" /**注冊對象， 被@JsPlugin注解標記的對象會自動注入，並調用空參的構造函數，\n 如果需要重寫構造，需保留空參的構造，並調用此方法注冊\n */\n");
writer.write(" public void register(String name,Object obj){\n");
writer.write(" map.put(name,obj);\n");
writer.write(" }\n");
writer.write(" public Object queryJavaObject(String name){\n");
writer.write(" return map.get(name);\n");
writer.write(" }\n");
/* writer.write(" public void callJsReady(com.liwg.jsbridge.library.BridgeWebView webview){\n");
writer.write(" webview.callJsMethod(\"JSBridgeReady()\");\n");
writer.write(" }\n");*/
writer.write(" }\n");
} 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);
}
}
生成的代碼
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對象名和java對象的映射
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}}";
}
/**注冊對象， 被@JsPlugin注解標記的對象會自動注入，並調用空參的構造函數，
如果需要重寫構造，需保留空參的構造，並調用此方法注冊
*/
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
- 注入的插件對象必須實現JsPlugin接口,所有需要注入的對象必須繼承JsPlugin這個類並且 加上 @JsInject 注解標記
- 被 @JsInject 標記的類會被自動注入，並調用空參的構造創建對象，如果有自定義構造 可以使用 webView.getJsBridge().register()
- 如果該類中的方法不希望被注入可以 使用 @JsInject 注解上的 filter參數過濾掉
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調用我", 1).show();
jsFunction.execute("test execute " + s);
}
public void test1() {
Log.e("-------", "test1: ");
}
public void test2() {
Log.e("-------", "test2: ");
}
}
}
HTML&JS代碼
<html>
<script>
// 推薦使用方式，否則直接調用將無法調用到 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>
網頁預加載
//預加載，推薦在Application中調用
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"));
}
}
項目結構圖
參考項目https://github.com/lwugang/safe-java-js-webview-bridge
參考項目https://github.com/dukeland/EasyJSWebView
android js 互相調用
注：本文著作權歸作者，由demo大師代發，拒絕轉載，轉載需要作者授權