Android 在XML文件中控件监听，在Activity中实现不了，有异常IllegalStateException

Question

1. activity_main.xml

android:id="@+id/btLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="登陆"
android:layout_alignParentRight="true"
android:onClick="login"
/>

1. Activity代码

public class MainActivity extends Activity {
EditText etUserName = null;
EditText etPassword = null;
CheckBox cb = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

    etUserName = (EditText) findViewById(R.id.etUserName);
    etPassword = (EditText) findViewById(R.id.etPassword);
    cb = (CheckBox) findViewById(R.id.cb);
}


public void login(View view){
    String userName = etUserName.getText().toString().trim();
    String password = etPassword.getText().toString().trim();
    if(TextUtils.isEmpty(userName)||TextUtils.isEmpty(password)){
        Toast.makeText(this, "用户名或密码不能为空", Toast.LENGTH_SHORT).show();
    } else {
        //判断用户是否记住密码
        if(cb.isChecked()){
            //保存用户名密码
            Log.i("tag", "需要记住密码");
        }
        //登陆发送消息到服务器，服务器验证是否正确
        if("zhangsan".equals(userName)&&"123".equals(password)){
            Toast.makeText(this, "登陆成功", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(this, "登陆失败，用户名或密码错误", Toast.LENGTH_SHORT).show();
        }
    }
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

}

log中的不知道怎么复制上来----04-14 20:56:37.910: E/AndroidRuntime(1142): java.lang.IllegalStateException: Could not find a method login(View) in the activity class com.example.login.MainActivity for onClick handler on view class android.widget.Button with id 'btLogin'

Answer 1

android1.6以上才能使用，并且只能给Button控件使用，好像是这样的。你检查看看，我看没什么错误。