需要先准备几个工具，
用Android Studio编写一个简单的小项目下一章使用。
chapter1.png
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private EditText mUsername;
private EditText mPwd;
private static final String REAL_USERNAME = "282921012";
private static final String REAL_PWD = "123456";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mUsername = findViewById(R.id.etUsername);
mPwd = findViewById(R.id.etPwd);
findViewById(R.id.btnLogin).setOnClickListener(this);
}
@Override
public void onClick(View v) {
checkLogin();
}
private void checkLogin() {
String username = mUsername.getText().toString();
String pwd = mPwd.getText().toString();
if (TextUtils.equals(REAL_USERNAME, username) && TextUtils.equals(REAL_PWD, pwd)) {
Toast.makeText(this, R.string.login_success, Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(this, R.string.login_failed, Toast.LENGTH_SHORT).show();
}
}
}
实现的功能也很容易，如果输入的账号是282921012，输入的密码是123456，那么提示登录成功，否则提示登录失败。
