登录和记住密码关于SharedPreferences存储密码

（1.）登录和记住密码关于SharedPreferences存储密码

主Activity发送广播。

public class MainActivity extends Activity {

private Button forceOffLine;

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

forceOffLine= (Button) findViewById(R.id.force_offline);
forceOffLine.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
Intent intent = new Intent("com.example.broadcastbestpractice.FORCE_OFFLINE");
sendBroadcast(intent);
}
});
}

}

（2.）对登录界面的操作

/* 登录界面的操作和编写 /

public class LoginActivity extends BaseActivity {

private EditText accountEdit;
private EditText passwordEdit;
private Button login;
private SharedPreferences pref;
private CheckBox rememberPass;

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

pref = PreferenceManager.getDefaultSharedPreferences(this);
accountEdit = (EditText) findViewById(R.id.account);
passwordEdit = (EditText) findViewById(R.id.password);
/** 是否记住密码 */
rememberPass = (CheckBox) findViewById(R.id.remember_pass);
login = (Button) findViewById(R.id.login);
boolean isRemember = pref.getBoolean("remember_password", false);

if (isRemember) {
/** 要记住密码，将账号和密码设置到文本当中去 */
String account = pref.getString("account", "");
String password = pref.getString("password", "");
accountEdit.setText(account);
passwordEdit.setText(password);
rememberPass.setChecked(true);
}

login.setOnClickListener(new OnClickListener() {
private Editor editor;

@Override
public void onClick(View v) {
String account = accountEdit.getText().toString();
String password = passwordEdit.getText().toString();
/** 如果账号是admin且密码是123456，就默认登录成功 */
if (account.equals("admin") && password.equals("123456")) {
editor = pref.edit();
/** 检查是否被选中,如果是选中的状态，则进行保存密码，并且更改Boolean的值为true */
if (rememberPass.isChecked()) {
editor.putBoolean("remember_password", true);
editor.putString("account", account);
editor.putString("password", password);
}else{
/** 如果没有选中的话，调用此方法将SharedPreferences数据全部清除掉 */
editor.clear();
}
editor.commit();
Intent intent = new Intent(LoginActivity.this,
MainActivity.class);
startActivity(intent);
finish();
} else {
Toast.makeText(LoginActivity.this,
"account or password is invalid",
Toast.LENGTH_SHORT).show();
}
}
});
}

}

（3.）接收广播并作出相应的处理

public class ForceOfflineReceiver extends BroadcastReceiver{

@Override
public void onReceive(final Context context, Intent intent) {
AlertDialog.Builder  dialogBuilder = new AlertDialog.Builder(context);

dialogBuilder.setTitle("警告");
dialogBuilder.setMessage("您要强制下线，请重新登录");
dialogBuilder.setCancelable(false);
dialogBuilder.setPositiveButton("OK", new DialogInterface.OnClickListener() {

@Override
public void onClick(DialogInterface dialog, int which) {
/** 销毁所以的活动 */
ActivityCollector.finishAll();
Intent intent = new Intent(context,LoginActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
/** 重新启动LoginActivity */
context.startActivity(intent);
}
});

AlertDialog alertDialog = dialogBuilder.create();

/** 需要设置AlertDialog的类型，保证广播接收器可以正常的弹出 */
alertDialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
alertDialog.show();
}

}

（4.）

public class BaseActivity extends Activity{

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

}

@Override
protected void onDestroy() {
super.onDestroy();
ActivityCollector.removeActivity(this);

}

}

（5.） Activity管理器来管理所有的Activity的活动

public class ActivityCollector {

public static List<Activity> activities = new ArrayList<Activity>();

public static void AddActivity(Activity activity){
activities.add(activity);
}

public static void removeActivity(Activity activity){
activities.remove(activity);
}

public static void finishAll(){
for (Activity activity : activities) {
if (!activity.isFinishing()) {
activity.finish();
}
}
}

}