在这里粘贴一些代码，我需要帮助找出错误。一切正常，直到我开始搞乱创建AlertDialogFragment，现在RegisterFragment抛出异常。
logcat的：
05-25 11:36:25.168: D/LoginActivity(4173): showRegister() invoked
05-25 11:36:25.168: D/LoginActivity(4173): bundle put
05-25 11:36:25.238: D/AndroidRuntime(4173): Shutting down VM
05-25 11:36:25.248: W/dalvikvm(4173): threadid=1: thread exiting with uncaught exception (group=0xb3a95ba8)
05-25 11:36:25.268: E/AndroidRuntime(4173): FATAL EXCEPTION: main
05-25 11:36:25.268: E/AndroidRuntime(4173): Process: com.lamesauce.atplogbook, PID: 4173
05-25 11:36:25.268: E/AndroidRuntime(4173): java.lang.IllegalStateException: Could not execute method of the activity
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.view.View$1.onClick(View.java:3823)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.view.View.performClick(View.java:4438)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.view.View$PerformClick.run(View.java:18422)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.os.Handler.handleCallback(Handler.java:733)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.os.Handler.dispatchMessage(Handler.java:95)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.os.Looper.loop(Looper.java:136)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.app.ActivityThread.main(ActivityThread.java:5017)
05-25 11:36:25.268: E/AndroidRuntime(4173): at java.lang.reflect.Method.invokeNative(Native Method)
05-25 11:36:25.268: E/AndroidRuntime(4173): at java.lang.reflect.Method.invoke(Method.java:515)
05-25 11:36:25.268: E/AndroidRuntime(4173): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-25 11:36:25.268: E/AndroidRuntime(4173): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-25 11:36:25.268: E/AndroidRuntime(4173): at dalvik.system.NativeStart.main(Native Method)
05-25 11:36:25.268: E/AndroidRuntime(4173): Caused by: java.lang.reflect.InvocationTargetException
05-25 11:36:25.268: E/AndroidRuntime(4173): at java.lang.reflect.Method.invokeNative(Native Method)
05-25 11:36:25.268: E/AndroidRuntime(4173): at java.lang.reflect.Method.invoke(Method.java:515)
05-25 11:36:25.268: E/AndroidRuntime(4173): at android.view.View$1.onClick(View.java:3818)
05-25 11:36:25.268: E/AndroidRuntime(4173): ... 11 more
05-25 11:36:25.268: E/AndroidRuntime(4173): Caused by: java.lang.NullPointerException
05-25 11:36:25.268: E/AndroidRuntime(4173): at com.lamesauce.atplogbook.RegistrationFragment.<init>(RegistrationFragment.java:19)
05-25 11:36:25.268: E/AndroidRuntime(4173): at com.lamesauce.atplogbook.LoginActivity.showRegister(LoginActivity.java:102)
05-25 11:36:25.268: E/AndroidRuntime(4173): ... 14 more
这是调用方法：
public void showRegister(View view) {
Log.d(TAG, "showRegister() invoked");
EditText emailText = (EditText) findViewById(R.id.edittextEmail);
String registerEmail = emailText.getText().toString();
Bundle newBundle = new Bundle();
newBundle.putString("registerEmail", registerEmail);
Log.d(TAG, "bundle put");
RegistrationFragment newFragment = new RegistrationFragment();
Log.d(TAG, "new fragment created");
newFragment.setArguments(newBundle);
Log.d(TAG, "setArguments()");
...
}
应该加载的片段：
package com.lamesauce.atplogbook;
import android.app.ProgressDialog;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class RegistrationFragment extends Fragment {
private static final String TAG = RegistrationFragment.class
.getSimpleName();
private Utils utils = new Utils();
final User user = (User) this.getActivity().getApplicationContext();
private String registrationEmail;
private String password1;
private String password2;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_register, container,
false);
final EditText registerEmail = (EditText) view
.findViewById(R.id.edittextRegisterEmail);
final EditText registerPassword = (EditText) view
.findViewById(R.id.edittextRegisterPassword);
final EditText registerPassword2 = (EditText) view
.findViewById(R.id.edittextPasswordAgain);
// set up button onClickListener
Button registerButton = (Button) view
.findViewById(R.id.buttonTryRegister);
registerButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Attempt to create a new account on Parse.com
Log.d(TAG, "trying to register");
// EditText emailText = (EditText)
// view.findViewById(R.id.edittextRegisterEmail);
registrationEmail = (String) registerEmail.getText().toString();
if (utils.isValidEmail(registrationEmail)) {
Log.d(TAG, "good email");
} else {
Log.d(TAG, "bad email");
Toast.makeText(getActivity(), "invalid email address",
Toast.LENGTH_SHORT).show();
registerEmail.selectAll();
registerEmail.setFocusableInTouchMode(true);
registerEmail.requestFocus();
return;
}
// do passwords match?
password1 = (String) registerPassword.getText().toString();
password2 = (String) registerPassword2.getText().toString();
if (password1.equals(password2)) {
Log.d(TAG, "passwords match, continuing");
} else {
Log.d(TAG, "passwords do not match");
Toast.makeText(getActivity(), "passwords do not match",
Toast.LENGTH_SHORT).show();
// Give the password field the focus
registerPassword.setFocusableInTouchMode(true);
registerPassword.requestFocus();
return;
}
if (password1.length() < 6) {
Log.d(TAG, "Password not 6 characters");
Toast.makeText(getActivity(),
"password must be 6 characters minimum",
Toast.LENGTH_SHORT).show();
return;
}
// TODO
// try to register
boolean success = false;
boolean retry = true;
int attempts = 0;
do {
attempts++;
Log.d(TAG, "send attempt: " + Float.toString(attempts));
success = sendRegistration();
// retry = utils.showConfirmationBox(
// "try registration again?", getActivity());
retry = false;
} while (retry);
// success result
// fail result
// try again
// yes
// return to thread try
// no
// close window
}
});
// finish up setting up the view
Bundle b = getArguments();
registerEmail.setText(b.getString("registerEmail"));
return view;
}
private boolean sendRegistration() {
boolean success = false;
final ProgressDialog myPd_ring = ProgressDialog.show(getActivity(),
"Trying to register", "Contacting server...");
myPd_ring.setCancelable(true);
new Thread(new Runnable() {
@Override
public void run() {
try {
Log.d(TAG, "running progress");
user.setLoginEmail(registrationEmail);
user.setLoginPassword(password1);
Thread.sleep(5000);
// delete this
} catch (Exception e) {
}
myPd_ring.dismiss();
}
}).start();
return success;
}
}