Android登录活动模板

时间:2013-07-01 21:52:05

标签: java android eclipse login android-activity

我应该在哪里以及在哪里添加代码才能使其正常工作? 默认情况下,它不执行任何操作,按钮显示“登录或注册”,但它不显示任何注册活动。 菜单中的“恢复丢失的密码”也没有任何作用。 通过在finish()之后创建一个intent,我设法在签名后打开一个新活动; 虽然它无论电子邮件和密码如何都能成功登录!

编辑:这是代码!

public class LoginActivity extends Activity 
{
/**
 * A dummy authentication store containing known user names and passwords.
 * TODO: remove after connecting to a real authentication system.
 */
private static final String[] CREDENTIALS = new String[] 
        {
        "myaccount1@gmail.com:12345", "myaccount2@gmail.com:54321" 
        };

/**
 * The default email to populate the email field with.
 */
public static final String EXTRA_EMAIL = "myaccount1@gmail.com";

/**
 * Keep track of the login task to ensure we can cancel it if requested.
 */
private UserLoginTask mAuthTask = null;

// Values for email and password at the time of the login attempt.
private String mEmail;
private String mPassword;

// UI references.
private EditText mEmailView;
private EditText mPasswordView;
private View mLoginFormView;
private View mLoginStatusView;
private TextView mLoginStatusMessageView;

@Override
protected void onCreate(Bundle savedInstanceState) 
{
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_login);

    // Set up the login form.
    mEmail = getIntent().getStringExtra(EXTRA_EMAIL);
    mEmailView = (EditText) findViewById(R.id.email);
    mEmailView.setText(mEmail);

    mPasswordView = (EditText) findViewById(R.id.password);
    mPasswordView
            .setOnEditorActionListener(new TextView.OnEditorActionListener() 
            {
                @Override
                public boolean onEditorAction(TextView textView, int id,
                        KeyEvent keyEvent) 
                {
                    if (id == R.id.login || id == EditorInfo.IME_NULL) 
                    {
                        attemptLogin();
                        return true;
                    }
                    return false;
                }
            });

    mLoginFormView = findViewById(R.id.login_form);
    mLoginStatusView = findViewById(R.id.login_status);
    mLoginStatusMessageView = (TextView) findViewById(R.id.login_status_message);

    findViewById(R.id.sign_in_button).setOnClickListener(
            new View.OnClickListener() 
            {
                @Override
                public void onClick(View view) 
                {
                    attemptLogin();
                }
            });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) 
{
    super.onCreateOptionsMenu(menu);
    getMenuInflater().inflate(R.menu.activity_login, menu);
    return true;
}

/**
 * Attempts to sign in or register the account specified by the login form.
 * If there are form errors (invalid email, missing fields, etc.), the
 * errors are presented and no actual login attempt is made.
 */
public void attemptLogin() 
{
    if (mAuthTask != null) 
    {
        return;
    }

    // Reset errors.
    mEmailView.setError(null);
    mPasswordView.setError(null);

    // Store values at the time of the login attempt.
    mEmail = mEmailView.getText().toString();
    mPassword = mPasswordView.getText().toString();

    boolean cancel = false;
    View focusView = null;

    // Check for a valid password.
    if (TextUtils.isEmpty(mPassword)) 
    {
        mPasswordView.setError(getString(R.string.error_field_required));
        focusView = mPasswordView;
        cancel = true;
    } else if (mPassword.length() < 4) 
    {
        mPasswordView.setError(getString(R.string.error_invalid_password));
        focusView = mPasswordView;
        cancel = true;
    }

    // Check for a valid email address.
    if (TextUtils.isEmpty(mEmail)) 
    {
        mEmailView.setError(getString(R.string.error_field_required));
        focusView = mEmailView;
        cancel = true;
    } else if (!mEmail.contains("@")) 
    {
        mEmailView.setError(getString(R.string.error_invalid_email));
        focusView = mEmailView;
        cancel = true;
    }

    if (cancel) 
    {
        // There was an error; don't attempt login and focus the first
        // form field with an error.
        focusView.requestFocus();
    } else 
    {
        // Show a progress spinner, and kick off a background task to
        // perform the user login attempt.
        mLoginStatusMessageView.setText(R.string.login_progress_signing_in);
        showProgress(true);
        mAuthTask = new UserLoginTask();
        mAuthTask.execute((Void) null);
    }
}

/**
 * Shows the progress UI and hides the login form.
 */
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2)
private void showProgress(final boolean show) 
{
    // On Honeycomb MR2 we have the ViewPropertyAnimator APIs, which allow
    // for very easy animations. If available, use these APIs to fade-in
    // the progress spinner.
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) 
    {
        int shortAnimTime = getResources().getInteger(
                android.R.integer.config_shortAnimTime);

        mLoginStatusView.setVisibility(View.VISIBLE);
        mLoginStatusView.animate().setDuration(shortAnimTime)
                .alpha(show ? 1 : 0)
                .setListener(new AnimatorListenerAdapter() 
                {
                    @Override
                    public void onAnimationEnd(Animator animation) 
                    {
                        mLoginStatusView.setVisibility(show ? View.VISIBLE
                                : View.GONE);
                    }
                });

        mLoginFormView.setVisibility(View.VISIBLE);
        mLoginFormView.animate().setDuration(shortAnimTime)
                .alpha(show ? 0 : 1)
                .setListener(new AnimatorListenerAdapter() 
                {
                    @Override
                    public void onAnimationEnd(Animator animation) 
                    {
                        mLoginFormView.setVisibility(show ? View.GONE
                                : View.VISIBLE);
                    }
                });
    } else 
    {
        // The ViewPropertyAnimator APIs are not available, so simply show
        // and hide the relevant UI components.
        mLoginStatusView.setVisibility(show ? View.VISIBLE : View.GONE);
        mLoginFormView.setVisibility(show ? View.GONE : View.VISIBLE);
    }
}

/**
 * Represents an asynchronous login/registration task used to authenticate
 * the user.
 */
public class UserLoginTask extends AsyncTask<Void, Void, Boolean> 
{
    @Override
    protected Boolean doInBackground(Void... params) 
    {
        // TODO: attempt authentication against a network service.

        try 
        {
            // Simulate network access.
            Thread.sleep(2000);
        } catch (InterruptedException e) 
        {
            return false;
        }

        for (String credential : CREDENTIALS) 
        {
            String[] pieces = credential.split(":");
            if (pieces[0].equals(mEmail)) 
            {
                // Account exists, return true if the password matches.
                return pieces[1].equals(mPassword);
            }
        }

        // TODO: register the new account here.
        //CREDENTIALS[2]=mEmail+":"+mPassword;  tried this for regisration
        return true;
    }

    @Override
    protected void onPostExecute(final Boolean success) 
    {
        mAuthTask = null;
        showProgress(false);

        if (success) 
        {
            finish();
            Intent myIntent = new Intent(LoginActivity.this,CalculatorActivity.class);
            LoginActivity.this.startActivity(myIntent);
        } else 
        {
            mPasswordView
                    .setError(getString(R.string.error_incorrect_password));
            mPasswordView.requestFocus();
        }
    }

    @Override
    protected void onCancelled() 
    {
        mAuthTask = null;
        showProgress(false);
    }
}

}

这适用于CREDENTIALS中的默认字符串,但我不知道如何实现注册过程,如何将这些mEmail和mPassword添加到CREDENTIALS字符串?

1 个答案:

答案 0 :(得分:1)

CREDENTIALS只是在程序的前几行中定义的字符串数组,您可以手动编辑它。例如:

private static final String[] CREDENTIALS = new String[] 
        {
        "myaccount1@gmail.com:12345", "myaccount2@gmail.com:54321", "bla@bla.com:1234" 
        };

但是这个模板代码用于登录Web服务数据库或类似的东西。如果你想登录本地数据库,你不需要AsyncTask mumbo jumbo,你可以在attempt!= true时在trylogin()函数中编写验证码。