Android連接PHP和MySql強制關閉

Question

我正在編寫一個需要登錄和註冊的應用程序，所以我在網上查找一些教程。我也購買和在線託管服務器來存儲我的數據庫。但是，我在運行應用程序時不斷收到運行時錯誤。我一直在抓一整天，但仍然不知道這個問題。如果有人能給我一些提示或線索，我會很感激，謝謝。

登錄貓錯誤

11-14 22:22:13.071: E/AndroidRuntime(12901): FATAL EXCEPTION: main 
11-14 22:22:13.071: E/AndroidRuntime(12901): android.os.NetworkOnMainThreadException 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1118) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at java.net.InetAddress.lookupHostByName(InetAddress.java:385) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at java.net.InetAddress.getAllByName(InetAddress.java:214) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:670) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:509) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at com.example.trafficmaster.library.JSONParser.getJSONFromUrl(JSONParser.java:42) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at com.example.trafficmaster.library.UserFunctions.registerUser(UserFunctions.java:61) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at com.example.trafficmaster.RegisterActivity$1.onClick(RegisterActivity.java:55) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.view.View.performClick(View.java:4211) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.view.View$PerformClick.run(View.java:17267) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.os.Handler.handleCallback(Handler.java:615) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.os.Handler.dispatchMessage(Handler.java:92) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.os.Looper.loop(Looper.java:137) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at android.app.ActivityThread.main(ActivityThread.java:4898) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at java.lang.reflect.Method.invokeNative(Native Method) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at java.lang.reflect.Method.invoke(Method.java:511) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773) 
11-14 22:22:13.071: E/AndroidRuntime(12901): at dalvik.system.NativeStart.main(Native Method) 
11-14 22:22:18.251: D/dalvikvm(12901): GC_CONCURRENT freed 357K, 11% free 12504K/13895K, paused 4ms+9ms, total 46ms 
11-14 22:22:25.251: I/Process(12901): Sending signal. PID: 12901 SIG: 9 

我註冊主類

public class RegisterActivity extends Activity { 
    Button btnRegister; 
    Button btnLinkToLogin; 
    EditText inputFullName; 
    EditText inputEmail; 
    EditText inputPassword; 
    TextView registerErrorMsg; 

    // JSON Response node names 
    private static String KEY_SUCCESS = "success"; 
    private static String KEY_ERROR = "error"; 
    private static String KEY_ERROR_MSG = "error_msg"; 
    private static String KEY_UID = "uid"; 
    private static String KEY_NAME = "name"; 
    private static String KEY_EMAIL = "email"; 
    private static String KEY_CREATED_AT = "created_at"; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.register); 


     // Importing all assets like buttons, text fields 
     inputFullName = (EditText) findViewById(R.id.registerName); 
     inputEmail = (EditText) findViewById(R.id.registerEmail); 
     inputPassword = (EditText) findViewById(R.id.registerPassword); 
     btnRegister = (Button) findViewById(R.id.btnRegister); 
     btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen); 
     registerErrorMsg = (TextView) findViewById(R.id.register_error); 

     // Register Button Click event 
     btnRegister.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View view) { 

       new MyInnerClass().execute(); 

       String name = inputFullName.getText().toString(); 
       String email = inputEmail.getText().toString(); 
       String password = inputPassword.getText().toString(); 
       UserFunctions userFunction = new UserFunctions(); 
       JSONObject json = userFunction.registerUser(name, email, password); 

       // check for login response 
       try { 
        if (json.getString(KEY_SUCCESS) != null) { 
         registerErrorMsg.setText(""); 
         String res = json.getString(KEY_SUCCESS); 
         if(Integer.parseInt(res) == 1){ 
          // user successfully registred 
          // Store user details in SQLite Database 
          DatabaseHandler db = new DatabaseHandler(getApplicationContext()); 
          JSONObject json_user = json.getJSONObject("user"); 

          // Clear all previous data in database 
          userFunction.logoutUser(getApplicationContext()); 
          db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT)); 
          // Launch Dashboard Screen 
          Intent dashboard = new Intent(getApplicationContext(), DashboardActivity.class); 
          // Close all views before launching Dashboard 
          dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
          startActivity(dashboard); 
          // Close Registration Screen 
          finish(); 
         }else{ 
          // Error in registration 
          registerErrorMsg.setText("Error occured in registration"); 
         } 
        } 
       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 
      } 
     }); 

Answer 1

你在主線程中執行（可能慢）的網絡操作。如果您的目標SDK爲11（Honeycomb）或更高，則會在Honeycomb或更高版本上拋出NetworkOnMainThreadException，因爲此行爲可能會阻止UI並導致應用程序無響應。

您可以使用AsyncTask來解決這個問題，將數據加載到它的doInBackground(..)中。

Answer 2

android.os.NetworkOnMainThreadException 

當您從主線程訪問網絡時會發生此異常。使用AsyncTask來訪問網絡。

private class MyInnerClass extends AsyncTask<String, Void, String> { 
    @Override 
    protected void onPreExecute() { 
    super.onPreExecute(); 

    } 

    @Override 
    protected String doInBackground(String params) { 

    return "Done"; 
    } 

    @Override 
    protected void onPostExecute(String result) { 
    super.onPostExecute(result); 
    } 
    } 

從您的主要活動和Android呼叫new MyInnerClass().execute();會自動調用onPreExecute()。這種方法是給你的WANA之前網絡接入

網絡相關的東西在裏面doInBackground()完成，然後Android將會調用onPostExecute()，結果會PARAMS這種方法傳遞做的東西。