1.映射Java对象到JavaScript对象上

MainActivity.java

package com.example.jsdemo; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.webkit.WebSettings; import android.webkit.WebView; public class MainActivity extends AppCompatActivity { private WebView wView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); wView = (WebView) findViewById(R.id.wView); wView.loadUrl("file:///android_asset/demo1.html"); WebSettings webSettings = wView.getSettings(); //①设置WebView允许调用js webSettings.setJavaScriptEnabled(true); webSettings.setDefaultTextEncodingName("UTF-8"); //②设置支持js调用java wView.addJavascriptInterface(new AndroidAndJSInterface(),"Android""); } class AndroidAndJSInterface{ @JavascriptInterface public void showToast(){ Toast.makeText(MainActivity.this, "我被js调用了", Toast.LENGTH_SHORT).show(); } } }

注意:解决该WebView.addJavascriptInterface接口不起作用的两种办法

①针对版本改成16

②在JavaScript接口类的方法加上@JavascriptInterface注解

2.JavaScript调用Java对象示例

demo1.html

<input type="button" value="点击Android被调用" />