Question

我正在将我的应用程序连接到我的服务器

以下是我访问互联网的表现文件

 <uses-sdk
    android:minSdkVersion="10"
    android:targetSdkVersion="19"/>
    <uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

它在API级别10中工作

但是当涉及到套件kat版本的API级别19时，它无法访问互联网，它会抛出异常。

我是否需要添加任何其他权限

这是我用来连接我服务器的代码

public class Discussion_server extends AsyncTask<String,Void,JSONObject> {


static String jsonstring="";
private Handler handler = new Handler();
private ProgressDialog dialog;
private Activity activity;

public Discussion_server(Activity activity)
{
    Log.d("progressing","progressing");
    this.activity = activity;
    this.dialog = new ProgressDialog(activity);
   // onPreExecute();
    dialog.setMessage("Contacting Remote Site");
    dialog.show();
  handler.postDelayed(new Runnable()
  {

    @Override
    public void run() {

        onExecute();    

    }

  },3000);


}


protected void onExecute(){ 


   dialog.dismiss();

}



@Override
protected JSONObject doInBackground(String... arg0) {
    // TODO Auto-generated method stub
     try{

    Log.d("boooooo","beeeee");
   // Toast.makeText(this,comment,Toast.LENGTH_LONG).show();
    String link="http://www.diveintojava.com/Discussion/mobile_discussion.php";

    HttpClient client = new DefaultHttpClient();
    HttpGet request = new HttpGet();
    request.setURI(new URI(link));
    HttpResponse response = client.execute(request);

    BufferedReader reader = new BufferedReader
    (new InputStreamReader(response.getEntity().getContent()));
    StringBuilder sb = new StringBuilder();


    String line=null;
   jsonstring="";
    while((line = reader.readLine()) != null)
    {
        Log.d("na","na");

        jsonstring+=(line+ "\n");
       //break;
    }
    //onPostExecute();
    return new JSONObject(jsonstring);
 }catch(Exception e){
     Log.d("veaadsldsld","sdlkfsdlfsldklfsd");
    Log.d("exc",e.getMessage());
    //Toast.makeText(activity,"Connection timed out!!",Toast.LENGTH_LONG).show();
     return null;
 }



}



}

这是我的logcat显示的内容

07-10 02:23:39.827: E/AndroidRuntime(838): FATAL EXCEPTION: main
07-10 02:23:39.827: E/AndroidRuntime(838): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.diveintojava1/com.example.diveintojava1.Discussion}: java.lang.NullPointerException: println needs a message
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180) 
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.ActivityThread.access$600(ActivityThread.java:141)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.os.Handler.dispatchMessage(Handler.java:99)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.os.Looper.loop(Looper.java:137)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.ActivityThread.main(ActivityThread.java:5041)
07-10 02:23:39.827: E/AndroidRuntime(838):  at java.lang.reflect.Method.invokeNative(Native Method)
07-10 02:23:39.827: E/AndroidRuntime(838):  at java.lang.reflect.Method.invoke(Method.java:511)
07-10 02:23:39.827: E/AndroidRuntime(838):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
07-10 02:23:39.827: E/AndroidRuntime(838):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
07-10 02:23:39.827: E/AndroidRuntime(838):  at dalvik.system.NativeStart.main(Native Method)
07-10 02:23:39.827: E/AndroidRuntime(838): Caused by: java.lang.NullPointerException: println needs a message
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.util.Log.println_native(Native Method)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.util.Log.d(Log.java:138)
07-10 02:23:39.827: E/AndroidRuntime(838):  at com.example.diveintojava1.Discussion_server.doInBackground(Discussion_server.java:100)
07-10 02:23:39.827: E/AndroidRuntime(838):  at com.example.diveintojava1.Discussion.onCreate(Discussion.java:78)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.Activity.performCreate(Activity.java:5104)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
07-10 02:23:39.827: E/AndroidRuntime(838):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
07-10 02:23:39.827: E/AndroidRuntime(838):  ... 11 more

Answer 1

使用过的网址＆＃34; http://www.diveintojava.com/Discussion/＆＃34;给出html输出。在您使用＆＃34; http://www.diveintojava.com/Discussion/mobile_discussion.php＆＃34;之前这给了json文本。你需要json解析器的json文本。

用于更高API级别的互联网连接的Android权限

1 个答案: