Js Java互相调用

两篇超详细的良心攻略

https://www.jianshu.com/p/3c94ae673e2a web view的api介绍

https://www.jianshu.com/p/345f4d8a5cfa java js互调

java调用js

准备一个html文件

html>



    charset="utf-8">
    

    

调用

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "xbh";

    private WebView wv;

    @SuppressLint("SetJavaScriptEnabled")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        FrameLayout fl = findViewById(R.id.fl);
        wv = new WebView(this);
        Button bt = findViewById(R.id.bt);

        fl.addView(wv);

        WebSettings ws = wv.getSettings();
        ws.setJavaScriptEnabled(true);
        ws.setJavaScriptCanOpenWindowsAutomatically(true);

        wv.loadUrl("file:///android_asset/javascript.html");

        wv.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageFinished(WebView view, String url) {
                Log.i(TAG, "LoadFinished: ");
                view.loadUrl("javascript:callJS()");
            }
        });

        wv.setWebChromeClient(new WebChromeClient() {
            @Override
            public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
                Log.i(TAG, "onJsAlert: " + url + " " + message + " " + result);
                return true;
            }
        });
    }
}

也可以用evaluateJavascript（）-》4.4以上用这个方法

js调用java

1.addJavascriptInterface（）

js代码

html>


    charset="utf-8">
    
    

java

package com.example.demo;

import android.annotation.SuppressLint;
import android.app.job.JobInfo;
import android.app.job.JobScheduler;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.JavascriptInterface;
import android.webkit.JsResult;
import android.webkit.ValueCallback;
import android.webkit.WebChromeClient;
import android.webkit.WebResourceRequest;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Button;
import android.widget.FrameLayout;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "xbh";

    private WebView wv;

    @SuppressLint("SetJavaScriptEnabled")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        FrameLayout fl = findViewById(R.id.fl);
        wv = new WebView(this);

        fl.addView(wv);

        wv.loadUrl("file:///android_asset/javascript.html");

        wv.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageFinished(WebView view, String url) {
                view.loadUrl("javascript:callAndroid()");
            }
        });

        WebSettings ws = wv.getSettings();
        ws.setJavaScriptEnabled(true);
        wv.addJavascriptInterface(new AndroidtoJs(), "test");//AndroidtoJS类对象映射到js的test对象
    }

    class AndroidtoJs{
        @JavascriptInterface
        public void hello(String msg) {
            Toast.makeText(MainActivity.this, msg, Toast.LENGTH_SHORT).show();
            Log.i(TAG, msg);
        }
    }
}

但是有漏洞

2.shouldOverrideUrlLoading拦截url

3.拦截alert()、confirm()、prompt（）

还有就是用JsBridge等框架