有一个网站提供了一些 javascript 来发出我需要的信息，有没有办法通过 androids API 来使用这个 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>
如果您在 html 文件中运行它，您会注意到它会显示从网站检索到的图像和文本，我想在一个 android 应用程序中获取所有这些信息。
【问题讨论】：
标签： java javascript android html web
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（可能是隐藏的？）并使用 javascript 接口拦截 javascript 调用，结合注入 webview 我想你应该能够做几乎所有你想做的事情。 如果您需要它，您还可以下载 js 源代码，根据需要对其进行解析，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，网络上到处都是例子，这里是 example 和 another one
编辑
好的，你不需要实际运行那个 javascript，解析它就足够了，这里是一个在 android 中实现 @T.S. 的工作示例。解析方法，要运行它，您只需将 android.permission.INTERNET 添加到您的清单文件并设置一个带有 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;
}
}
【讨论】：
如果只是为了显示，您可以使用带有一些自定义样式的WebView。
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);
更新
我写了一个快速而肮脏的示例，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;
}
}
}
}
它可以进行很多优化，并且在当前状态下可能不是故障安全的，但它可能会给你一些关于如何开始的提示。
【讨论】：