在Android应用程序中运行javascript?

时间:2013-05-16 12:20:46

标签: java javascript android html web

有一个网站提供了一些javascript,它可以发出我需要的信息,是否有通过机器人API的方法,使用这个javascript发出它拥有的任何信息并通过它解析?

这是javascript:

<script type="text/javascript" src="http://pulllist.comixology.com/js/pulllist/5b467b28e73595311e02fe32c3081e4a.js?date=2013-05-15"></script>

如果你在一个html文件中运行它,你会注意到它显示了从网站上检索的图像和文本,我想在Android应用程序中获取所有这些信息。

2 个答案:

答案 0 :(得分:2)

我不知道你是否可以直接运行javascript代码,但你可以在webview中运行它(可能是一个隐藏的?)并使用javascript界面​​拦截javascript调用,结合注入webview我认为你应该能够做你想要的几乎所有事情。 如果您需要它,您也可以下载js源代码,根据需要解析它,然后将其提供给webview。如果您想了解更多信息,请告诉我^^

无论如何,网页上都充满了示例,这里有exampleanother one

修改
好吧你不需要实际运行那个javascript,解析它就足够了,这里有一个在Android实现@T.S的工作示例。解析方法,要运行它,您只需要将android.permission.INTERNET添加到清单文件并设置带有myTextView id的textview。

public class MainActivity extends Activity implements Runnable{
    TextView myTextView;

    public Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg){

            String source = (String)msg.obj;                        
            // The index of the item
            int i = 0;

            // We search the data-string from the start
            int position1 = 0;

            // While there are items found, continue
            while(true) {

                // Look for the pattern a[index]={json data};
                String lookFor1 = "a[" + String.valueOf(i) + "]={";
                String lookFor2 = "};";
                position1  = source.indexOf(lookFor1, position1+1);

                // Check if we have a match
                if(position1 > -1) {

                    // Find the end of the match
                    int position2 = source.indexOf(lookFor2, position1);

                    // Get the result
                    String result = source.substring(position1 + lookFor1.length() - 1, position2 + 1);

                    // Increase the index an check if we can find a next item
                    i++;

                    // Print out this row, which is a JSON representation of the data you want
                    Log.e("res",result);
                    try {
                        JSONObject obj = new JSONObject(result);
                        String title = obj.getString("title");
                        String img = obj.getString("img");
                        String src = new JSONObject(img).getString("src");
                        myTextView.append("\ntitle: "+title+"\nimgurl: "+src+"\n");
                    } catch (JSONException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }

                } else {
                    // We haven't found a match, break out of while loop
                    break;
                }
            }
        }
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        myTextView = (TextView) findViewById(R.id.myTextView);

        Thread thread = new Thread(this);
        thread.start();
    }

    @Override
    public void run() {
        String data = retrieve_data();
        Message msg = handler.obtainMessage();
        msg.obj = data;
        handler.sendMessage(msg);

    }

    private String retrieve_data(){

        String data = "";
        String url = "http://pulllist.comixology.com/js/pulllist/5b467b28e73595311e02fe32c3081e4a.js?date=2013-05-15";
        HttpClient httpclient = new DefaultHttpClient();

        HttpGet request;
        try {
            request = new HttpGet(new URI(url));
            request.addHeader("User-Agent", "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:21.0) Gecko/20100101 Firefox/21.0");

            HttpResponse response = httpclient.execute(request);
            StatusLine statusLine = response.getStatusLine();
            if (statusLine.getStatusCode() == HttpStatus.SC_OK) {
                ByteArrayOutputStream out = new ByteArrayOutputStream();
                response.getEntity().writeTo(out);
                out.close();
                data = out.toString();
            }
        } catch (URISyntaxException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return data;
    }



}

答案 1 :(得分:1)

如果它仅用于显示,您可以使用WebView一些自定义样式。 链接:http://developer.android.com/reference/android/webkit/WebView.html

String html = "<script type='text/javascript' src='http://pulllist.comixology.com/js/pulllist/5b467b28e73595311e02fe32c3081e4a.js?date=2013-05-15'></script>";
String mime = "text/html";
String encoding = "utf-8";

WebView myWebView = (WebView)this.findViewById(R.id.myWebView);
myWebView.getSettings().setJavaScriptEnabled(true);
myWebView.loadDataWithBaseURL(null, html, mime, encoding, null);

<强>更新

我写了一个快速而又脏的例子,说明如何从该javascript文件中提取数据:

import java.util.*;
import java.lang.*;
import java.net.*;
import java.io.*;

public class JavascriptToUsableData {

    // Method to get a string from an URL
    // Thanks to http://stackoverflow.com/a/4328733/1226267
    public static String getText(String url) throws Exception {
        URL website = new URL(url);
        URLConnection connection = website.openConnection();
        BufferedReader in = new BufferedReader(
                                new InputStreamReader(
                                    connection.getInputStream()));

        StringBuilder response = new StringBuilder();
        String inputLine;

        while ((inputLine = in.readLine()) != null) 
            response.append(inputLine);

        in.close();

        return response.toString();
    }

    public static void main (String args[]) throws Exception {

        // Get the data
        String source = JavascriptToUsableData.getText("http://pulllist.comixology.com/js/pulllist/5b467b28e73595311e02fe32c3081e4a.js?date=2013-05-15");

        // The index of the item
        int i = 0;

        // We search the data-string from the start
        int position1 = 0;

        // While there are items found, continue
        while(true) {

            // Look for the pattern a[index]={json data};
            String lookFor1 = "a[" + String.valueOf(i) + "]={";
            String lookFor2 = "};";
            position1  = source.indexOf(lookFor1, position1+1);

            // Check if we have a match
            if(position1 > -1) {

                // Find the end of the match
                int position2 = source.indexOf(lookFor2, position1);

                // Get the result
                String result = source.substring(position1 + lookFor1.length() - 1, position2 + 1);

                // Increase the index an check if we can find a next item
                i++;

                // Print out this row, which is a JSON representation of the data you want
                System.out.println(result);

                // I'm not in an Android environment right now, but there is a JSON reader you can use in Android
                // I think it works somthing like this:
                // resultObj = new JSONObject(result);

                // And then access the data like this:
                // resultObj.getString("title");
                // resultObj.getString("guid");
                // resultObj.getString("img");
                // etc

            } else {
                // We haven't found a match, break out of while loop
                break;
            }
        }
    }
}

它可以进行大量优化,并且可能在当前状态下不是故障安全的,但它可能会给你一些如何启动的提示。