Android中的HTTP POST，強制關閉？

Question

我試圖通過Android發送一個簡單的HTTP請求，當我按下某個按鈕時。但每次我這樣做，我的應用程序部隊就會關閉。爲什麼？順便說一句，我是Android新手。

我的代碼：

HttpClient httpclient = new DefaultHttpClient(); 
HttpPost httppost = new HttpPost("http://www.office.school-blog.de/api/check-login.php"); 

try { 
    // Add your data 
    List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2); 
    nameValuePairs.add(new BasicNameValuePair("User", "Steffen")); 
    nameValuePairs.add(new BasicNameValuePair("Password", "test1234")); 
    httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs)); 

    // Execute HTTP Post Request 
    HttpResponse response = httpclient.execute(httppost); 

} catch (ClientProtocolException e) { 
    // TODO Auto-generated catch block 
} catch (IOException e) { 
    // TODO Auto-generated catch block 
} 

我的日誌文件：

03-16 14:36:47.554: D/AndroidRuntime(449): Shutting down VM 
03-16 14:36:47.554: W/dalvikvm(449): threadid=1: thread exiting with uncaught exception (group=0x40014760) 
03-16 14:36:47.574: E/AndroidRuntime(449): FATAL EXCEPTION: main 
03-16 14:36:47.574: E/AndroidRuntime(449): android.os.NetworkOnMainThreadException 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1077) 
03-16 14:36:47.574: E/AndroidRuntime(449): at java.net.InetAddress.lookupHostByName(InetAddress.java:477) 
03-16 14:36:47.574: E/AndroidRuntime(449): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:277) 
03-16 14:36:47.574: E/AndroidRuntime(449): at java.net.InetAddress.getAllByName(InetAddress.java:249) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:136) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 
03-16 14:36:47.574: E/AndroidRuntime(449): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465) 
03-16 14:36:47.574: E/AndroidRuntime(449): at com.shr.khg.DashboardActivity$1.onClick(DashboardActivity.java:89) 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.view.View.performClick(View.java:3110) 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.view.View$PerformClick.run(View.java:11934) 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.os.Handler.handleCallback(Handler.java:587) 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.os.Handler.dispatchMessage(Handler.java:92) 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.os.Looper.loop(Looper.java:132) 
03-16 14:36:47.574: E/AndroidRuntime(449): at android.app.ActivityThread.main(ActivityThread.java:4123) 
03-16 14:36:47.574: E/AndroidRuntime(449): at java.lang.reflect.Method.invokeNative(Native Method) 
03-16 14:36:47.574: E/AndroidRuntime(449): at java.lang.reflect.Method.invoke(Method.java:491) 
03-16 14:36:47.574: E/AndroidRuntime(449): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841) 
03-16 14:36:47.574: E/AndroidRuntime(449): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599) 
03-16 14:36:47.574: E/AndroidRuntime(449): at dalvik.system.NativeStart.main(Native Method) 
03-16 14:36:50.064: I/Process(449): Sending signal. PID: 449 SIG: 9 

有誰知道什麼是錯？

Answer 1

使用AsyncTask。

不要做在主線程中的網絡操作：這是不允許的Android版本> = 3.0。在doInBackground方法

做網絡操作。

閱讀here。

Answer 2

Android不允許阻塞的任務，如在UI的網絡接入（或主）線程。這是所有與用戶交互操作有關的線程運行。因此，您需要創建（可能）和AsynTask類來運行查詢並將信息反饋回來。見http://developer.android.com/reference/android/os/AsyncTask.html。一個的AsyncTask的一個例子也是在這裏給出：http://www.javasrilankansupport.com/2012/11/asynctask-android-example-asynctask-in.html

Answer 3

You are trying to perform network operation on UI thread，儘量採取單獨的線程或異步任務

Answer 4

這將解決你的問題：

class MyHttpPost extends AsyncTask<String, Void, Boolean> { 
@Override 
protected Boolean doInBackground(String... params) 
{ 

HttpClient httpclient = new DefaultHttpClient(); 
HttpPost httppost = new HttpPost("http://www.office.school-blog.de/api/check-login.php"); 

     try { 
     // Add your data 
     List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2); 
     nameValuePairs.add(new BasicNameValuePair("User", "Steffen")); 
     nameValuePairs.add(new BasicNameValuePair("Password", "test1234")); 
     httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs)); 

     // Execute HTTP Post Request 
     HttpResponse response = httpclient.execute(httppost); 
    HttpEntity httpEntity = response.getEntity(); 
       String result = httpEntity.getContent(); 


     } catch (ClientProtocolException e) { 
     // TODO Auto-generated catch block 
     } catch (IOException e) { 
     // TODO Auto-generated catch block 
     } 



return true; 
        } 

} 

替換上述代碼public class，因爲MyHttpPost類是內部類，所以我們不會爲它創建單獨的.java文件。

要使用它：

所有的

new MyHttpPost().execute();