Question

填写登录信息后，我无法转到下一页。不知道为什么？

public class SignUP extends Activity {
    EditText editTextUserName, editTextPassword, editTextConfirmPassword;
    Button btnCreateAccount;
    DataBaseAdapter loginDataBaseAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.reg);

        // get Instance  of Database Adapter
        loginDataBaseAdapter = new DataBaseAdapter(this);
        loginDataBaseAdapter = loginDataBaseAdapter.open();

        // Get Refferences of Views
        editTextUserName = (EditText)findViewById(R.id.editTextUserName);
        editTextPassword = (EditText)findViewById(R.id.editTextPassword);

        btnCreateAccount = (Button)findViewById(R.id.buttonCreateAccount);
        btnCreateAccount.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                String userName = editTextUserName.getText().toString();
                String password = editTextPassword.getText().toString();
                String confirmPassword = editTextConfirmPassword.getText().toString();

                // check if any of the fields are vaccant
                if (userName.equals("") || password.equals("") || confirmPassword.equals("")) {
                    Toast.makeText(getApplicationContext(), "Field Vaccant", Toast.LENGTH_LONG).show();
                    return;
                }
                // check if both password matches
                if (!password.equals(confirmPassword)) {
                    Toast.makeText(getApplicationContext(), "Password Does Not Matches", Toast.LENGTH_LONG).show();
                    return;
                }
                else {
                    // Save the Data in Database
                    loginDataBaseAdapter.insertEntry(userName, password);
                    Toast.makeText(getApplicationContext(), "Account Successfully Created ", Toast.LENGTH_LONG).show();
                    Intent menu = new Intent(getApplicationContext(), Menu.class);
                    startActivity(menu);
                }
            }
        });
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        loginDataBaseAdapter.close();
    }
}

logcat的：

08-13 15:09:37.476: E/AndroidRuntime(1113): FATAL EXCEPTION: main
08-13 15:09:37.476: E/AndroidRuntime(1113): Process: com.example.takeit, PID: 1113
08-13 15:09:37.476: E/AndroidRuntime(1113): java.lang.NullPointerException
08-13 15:09:37.476: E/AndroidRuntime(1113):     at com.example.takeit.SignUP$1.onClick(SignUP.java:46)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at android.view.View.performClick(View.java:4438)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at android.view.View$PerformClick.run(View.java:18422)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at android.os.Handler.handleCallback(Handler.java:733)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at android.os.Handler.dispatchMessage(Handler.java:95)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at android.os.Looper.loop(Looper.java:136)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at android.app.ActivityThread.main(ActivityThread.java:5017)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at java.lang.reflect.Method.invokeNative(Native Method)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at java.lang.reflect.Method.invoke(Method.java:515)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
08-13 15:09:37.476: E/AndroidRuntime(1113):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

您忘记初始化editTextConfirmPassword，因此也要初始化：

editTextConfirmPassword = (EditText)findViewById(R.id.editTextConfirmPassword);

未知原因App崩溃

1 个答案: