Android—android与js交互以及相互传参

Android中可以通过WebView来实现与js的交互,让用户可以在android客户端看到js写的页面,接下来为大家介绍的就是怎样实现此功能:

首先android项目目录下有“assets”文件夹,开发者需要将html文件拷贝到此文件夹下。

html代码:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!-- saved from url=(0032)http://localhost:8080/jsandroid/ -->
<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta http-equiv="Expires" content="0">
<meta http-equiv="Pragma" content="no-cache">
<meta http-equiv="Cache-Control" content="no-store,no-cache"> 
<meta name="Handheldfriendly" content="true">
<meta name="viewport" content="width=100%; initial-scale=1.0; user-scalable=yes">
<meta name="robots" content="all">
<meta name="keywords" contect="doodle, mobile, doodlemobile, game, games">
<meta name="description" content="Make People&#39;s Mobile Life More Connected Through Games.">
<title>jsandroid_test</title>
<script type="text/javascript" language="javascript"> 
//此方法是调用了android的方法HtmlcallJava2(); function showHtmlcallJava2(){ var str = document.getElementById("id_input").value var str1 = document.getElementById("id_input2").value
//调用android中的方法 window.jsObj.HtmlcallJava2(str
+","+str1); } </script> </head> <body> hello IT-homer <br> <br> <br> <br> <input id="id_input" style="width: 90%" type="text" value="null" /> <br> <br> <input id="id_input2" style="width: 90%" type="text" value="null" /> <br> </body> </html>

xml布局文件,很简单:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    tools:context=".JSAndroidActivity" >

    <WebView
        android:id="@+id/mWebView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="clickView"
        android:text="获取" />

</LinearLayout>
mainActivity中的核心代码是:
WebSettings webSettings = mWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
mWebView.addJavascriptInterface(jsInterface, "jsObj"); mWebView.loadUrl("file:///android_asset/index.html");
请理解核心代码的详细注释

mainActivity代码:
package com.homer.jsandroid;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;

import android.R.anim;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.os.Handler;
import android.view.KeyEvent;
import android.view.View;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.widget.TextView;
import android.widget.Toast;

public class JSAndroidActivity extends Activity {
    private Activity mActivity = null;
    private WebView mWebView = null;
    private String message;
    private JsInterface jsInterface;
    private String[] params = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mActivity = this;
        // 锁定横屏
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        setContentView(R.layout.main);
        params = new String[2];
        jsInterface = new JsInterface();
        showWebView();
    }

    @SuppressLint("SetJavaScriptEnabled")
    private void showWebView() {
        try {
            mWebView = (WebView) findViewById(R.id.mWebView);

            mWebView.requestFocus();

            mWebView.setWebChromeClient(new WebChromeClient() {
                @Override
                public void onProgressChanged(WebView view, int progress) {
                    JSAndroidActivity.this.setTitle("Loading...");
                    JSAndroidActivity.this.setProgress(progress);
                    if (progress >= 80) {
                        JSAndroidActivity.this.setTitle("JsAndroid Test");
                    }
                }
            });

            mWebView.setOnKeyListener(new View.OnKeyListener() {
                @Override
                public boolean onKey(View v, int keyCode, KeyEvent event) {
                    if (keyCode == KeyEvent.KEYCODE_BACK
                            && mWebView.canGoBack()) {
                        mWebView.goBack();
                        return true;
                    }
                    return false;
                }
            });
            // WebView的管理设置状态
            WebSettings webSettings = mWebView.getSettings();
            // 设置android下容许执行js的脚本
            webSettings.setJavaScriptEnabled(true);
            // 编码方式
            webSettings.setDefaultTextEncodingName("utf-8");
            /*
             * 使用这个函数将一个对象绑定到Javascript,因此可以从Javascript访问的方法,
             * Android(Java)与js(HTML)交互的接口函数, jsObj 为桥连对象可随意设值
             */
            mWebView.addJavascriptInterface(jsInterface, "jsObj");
            /*
             * Android(Java)访问js(HTML)端代码是通过loadUrl函数实现的,访问格式如:
             * mWebView.loadUrl("javascript: showFromHtml()");
             */
            mWebView.loadUrl("file:///android_asset/index.html");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private class JsInterface {
        /**
         * js中通过window.jsObj.HtmlcallJava2("参数") 可以调用此方法并且把js中input中的值作为参数传入,
         * 但这是在点击js中的按钮得到的,若实现点击java中的按钮得到,需要方法 clickView(View v)
         * 
         * @param param
         */
        public void HtmlcallJava2(final String param) {
            message = param;
            String str = message;
            StringTokenizer st = new StringTokenizer(str, ",;");
            while (st.hasMoreTokens()) {
                for (int i = 0; i < params.length; i++) {
                    params[i] = st.nextToken();
                    System.out.println(params[i]);
                }
            }
            Toast.makeText(JSAndroidActivity.this, param, Toast.LENGTH_SHORT)
                    .show();
        }
    }

    /**
     * button的点击事件
     * 
     * @param v
     */
    public void clickView(View v) {
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                /**
                 * 调用js中的方法实现点击java中的按钮得到js中input的值
                 */
                mWebView.loadUrl("javascript: showHtmlcallJava2()");
            }
        });
    }
}
希望给大家带来帮助,谢谢!

posted @ 2015-11-12 11:29  奋斗者—cyf  阅读(30899)  评论(0编辑  收藏  举报