我正在尝试使用 MySQL 数据库在 android 上编写一个简单的登录应用程序，并将用户信息存储在 SQLite 中，但出现大量错误。谁能指出我正确的方向？代码永远不会达到“成功登录！” 在doInBackground，我认为。
这是主要活动
public class MainActivity extends Activity {
JSONParser jsonParser = new JSONParser();
private ProgressDialog pDialog;
private static final String TAG_SUCCESS = "success";
// JSON Response node names
private static String KEY_UID = "uid";
private static String KEY_FIRSTNAME = "firstname";
private static String KEY_LASTNAME = "lastname";
private static String KEY_UNAME = "uname";
private static String KEY_EMAIL = "email";
Button bLogin;
EditText etUsername, etPassword;
TextView tvLError;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Login button
etUsername = (EditText) findViewById(R.id.etUsername);
etPassword = (EditText) findViewById(R.id.etPassword);
bLogin = (Button) findViewById(R.id.bLogin);
bLogin.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
new LoginTask().execute();
}
});
class LoginTask extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Logging in...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected String doInBackground(String... args) {
// TODO Auto-generated method stub
String uname = etUsername.getText().toString();
String password = etPassword.getText().toString();
UserFunctions userFunction = new UserFunctions();
JSONObject json = userFunction.loginUser(uname, password);
Log.d("Create Response", json.toString());
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// DATABASE HANDLER
// user successfully logged in
// 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_FIRSTNAME),
json_user.getString(KEY_LASTNAME),
json_user.getString(KEY_UNAME),
json_user.getString(KEY_EMAIL),
json_user.getString(KEY_UID));
tvLError.setText("Successfully logged in!");
} else {
tvLError.setText("Incorrect username/password");
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url) {
// dismiss the dialog once done
pDialog.dismiss();
}
}
JSONParser 类工作正常，Log.d 显示以下 JSON 对象
{"uid":"7","error":0,"user":
{"email":"abc@123.com","lastname":"test","uname":"test","firstname":"test"},
"success":1,"tag":"login"}
SQLite 的 DatabaseHandler 类
public class DatabaseHandler extends SQLiteOpenHelper{
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "android_api";
private static final String TABLE_LOGIN = "login";
private static final String KEY_ID = "id";
private static final String KEY_UNAME = "uname";
private static final String KEY_EMAIL = "email";
private static final String KEY_UID = "uid";
private static final String KEY_FIRSTNAME = "firstname";
private static final String KEY_LASTNAME = "lastname";
public DatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
String CREATE_LOGIN_TABLE = "CREATE TABLE " + TABLE_LOGIN + "("
+ KEY_ID + " INTEGER PRIMARY KEY,"
+ KEY_FIRSTNAME + " TEXT,"
+ KEY_LASTNAME + " TEXT,"
+ KEY_UNAME + " TEXT,"
+ KEY_EMAIL + " TEXT UNIQUE,"
+ KEY_UID + " TEXT" + ")";
db.execSQL(CREATE_LOGIN_TABLE);
}
public void addUser(String firstname, String lastname, String uname, String email, String uid) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_FIRSTNAME, firstname); // First name
values.put(KEY_LASTNAME, lastname); // Last name
values.put(KEY_UNAME, uname); // username
values.put(KEY_EMAIL, email); // Email
values.put(KEY_UID, uid); // User ID
// Inserting Row
db.insert(TABLE_LOGIN, null, values);
db.close(); // Closing database connection
}
和 UserFunctions 类中的 logoutUser 以防万一
/**
* Function to logout user
* Reset Database
* */
public boolean logoutUser(Context context){
DatabaseHandler db = new DatabaseHandler(context);
db.resetTables();
return true;
}
}
我得到的错误是
09-18 23:15:57.457: I/Process(807): Sending signal. PID: 807 SIG: 9
09-18 23:26:53.307: E/Trace(851): error opening trace file: No such file or directory (2)
09-18 23:26:53.717: I/Choreographer(851): Skipped 32 frames! The application may be doing too much work on its main thread.
09-18 23:26:53.787: D/gralloc_goldfish(851): Emulator without GPU emulation detected.
09-18 23:26:56.149: I/Choreographer(851): Skipped 32 frames! The application may be doing too much work on its main thread.
09-18 23:27:04.397: I/Choreographer(851): Skipped 60 frames! The application may be doing too much work on its main thread.
09-18 23:27:05.138: D/Create Response(851): {"uid":"7","error":0,"user":{"email":"abc@123.com","lastname":"test","uname":"test","firstname":"test"},"success":1,"tag":"login"}
09-18 23:27:05.437: I/Choreographer(851): Skipped 65 frames! The application may be doing too much work on its main thread.
09-18 23:27:05.477: D/dalvikvm(851): GC_CONCURRENT freed 175K, 3% free 8227K/8455K, paused 72ms+95ms, total 246ms
09-18 23:27:05.888: W/dalvikvm(851): threadid=11: thread exiting with uncaught exception (group=0x40a13300)
09-18 23:27:05.987: E/AndroidRuntime(851): FATAL EXCEPTION: AsyncTask #1
09-18 23:27:05.987: E/AndroidRuntime(851): java.lang.RuntimeException: An error occured while executing doInBackground()
09-18 23:27:05.987: E/AndroidRuntime(851): at android.os.AsyncTask$3.done(AsyncTask.java:299)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.lang.Thread.run(Thread.java:856)
09-18 23:27:05.987: E/AndroidRuntime(851): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:4607)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.ViewRootImpl.requestLayout(ViewRootImpl.java:835)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.View.requestLayout(View.java:15129)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.View.requestLayout(View.java:15129)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.View.requestLayout(View.java:15129)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.View.requestLayout(View.java:15129)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.view.View.requestLayout(View.java:15129)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.widget.TextView.checkForRelayout(TextView.java:6309)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.widget.TextView.setText(TextView.java:3547)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.widget.TextView.setText(TextView.java:3405)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.widget.TextView.setText(TextView.java:3380)
09-18 23:27:05.987: E/AndroidRuntime(851): at com.example.testapp1.MainActivity$LoginTask.doInBackground(MainActivity.java:148)
09-18 23:27:05.987: E/AndroidRuntime(851): at com.example.testapp1.MainActivity$LoginTask.doInBackground(MainActivity.java:1)
09-18 23:27:05.987: E/AndroidRuntime(851): at android.os.AsyncTask$2.call(AsyncTask.java:287)
09-18 23:27:05.987: E/AndroidRuntime(851): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
09-18 23:27:05.987: E/AndroidRuntime(851): ... 5 more
09-18 23:27:06.308: I/Choreographer(851): Skipped 44 frames! The application may be doing too much work on its main thread.
09-18 23:27:07.747: E/WindowManager(851): Activity com.example.testapp1.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@41219ee8 that was originally added here
09-18 23:27:07.747: E/WindowManager(851): android.view.WindowLeaked: Activity com.example.testapp1.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@41219ee8 that was originally added here
09-18 23:27:07.747: E/WindowManager(851): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:374)
09-18 23:27:07.747: E/WindowManager(851): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:292)
09-18 23:27:07.747: E/WindowManager(851): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
09-18 23:27:07.747: E/WindowManager(851): at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
09-18 23:27:07.747: E/WindowManager(851): at android.view.Window$LocalWindowManager.addView(Window.java:547)
09-18 23:27:07.747: E/WindowManager(851): at android.app.Dialog.show(Dialog.java:277)
09-18 23:27:07.747: E/WindowManager(851): at com.example.testapp1.MainActivity$LoginTask.onPreExecute(MainActivity.java:115)
09-18 23:27:07.747: E/WindowManager(851): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
09-18 23:27:07.747: E/WindowManager(851): at android.os.AsyncTask.execute(AsyncTask.java:534)
09-18 23:27:07.747: E/WindowManager(851): at com.example.testapp1.MainActivity$1.onClick(MainActivity.java:59)
09-18 23:27:07.747: E/WindowManager(851): at android.view.View.performClick(View.java:4084)
09-18 23:27:07.747: E/WindowManager(851): at android.view.View$PerformClick.run(View.java:16966)
09-18 23:27:07.747: E/WindowManager(851): at android.os.Handler.handleCallback(Handler.java:615)
09-18 23:27:07.747: E/WindowManager(851): at android.os.Handler.dispatchMessage(Handler.java:92)
09-18 23:27:07.747: E/WindowManager(851): at android.os.Looper.loop(Looper.java:137)
09-18 23:27:07.747: E/WindowManager(851): at android.app.ActivityThread.main(ActivityThread.java:4745)
09-18 23:27:07.747: E/WindowManager(851): at java.lang.reflect.Method.invokeNative(Native Method)
09-18 23:27:07.747: E/WindowManager(851): at java.lang.reflect.Method.invoke(Method.java:511)
09-18 23:27:07.747: E/WindowManager(851): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
09-18 23:27:07.747: E/WindowManager(851): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
09-18 23:27:07.747: E/WindowManager(851): at dalvik.system.NativeStart.main(Native Method)
感谢您的时间！