public class LoginActivity extends AppCompatActivity implements View.OnClickListener{

    TextView tv_register;
EditText et_name,et_password;
Button btn_login;
@Override
protected void onCreate( Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login
 
);
Bmob.initialize(this, "9d2b932612d7936e4cad1e81168b074d");
tv_register=(TextView)findViewById(R.id.tv_register);
btn_login=(Button)findViewById(R.id.btn_login);
et_name=(EditText)findViewById(R.id.et_login_username);
et_password=(EditText)findViewById(R.id.et_login_password);
tv_register.setOnClickListener(this
 
);
btn_login.setOnClickListener(this);
}

    @Override
public void onClick(View v) {
        switch (v.getId()){
            case R.id.tv_register:
                Intent intent=new Intent(LoginActivity.this,RegistrationActivity.class);
startActivity(intent);
                break;
            case 
 
R.id.btn_login:
                String name = et_name.getText().toString();
String password = et_password.getText().toString().trim();
                if(name.equals("")||password.equals("")){
                    Toast.makeText(LoginActivity.this, "賬號密碼不能為空", Toast.LENGTH_SHORT).show();
                    return;
}

                BmobUser user=new BmobUser();
user.setUsername(name);
user.setPassword(password);
user.login(new SaveListener<BmobUser>() {
                    @Override
public void done(BmobUser bmobuser, BmobException e) {

                        if(e==null){
                            Intent intent=new Intent(LoginActivity.this, MainActivity.class);
startActivity(intent);
}else{
                            Toast.makeText(LoginActivity.this, "登入失敗", Toast.LENGTH_SHORT).show();
}
                    }


                });
                break;
}

    }
}