Android数据绑定TextEdit验证两个或多个字段启用按钮

<EditText
    android:id="@+id/editText1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="@={viewModel.field1}" />

<EditText
    android:id="@+id/editText2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="@={viewModel.field2}" />

<Button
    android:id="@+id/button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Submit"
    android:enabled="@{viewModel.isValid}" />

public class MyViewModel extends BaseObservable {
    private String field1;
    private String field2;

    @Bindable
    public String getField1() {
        return field1;
    }

    public void setField1(String field1) {
        this.field1 = field1;
        notifyPropertyChanged(BR.field1);
        notifyPropertyChanged(BR.valid);
    }

    @Bindable
    public String getField2() {
        return field2;
    }

    public void setField2(String field2) {
        this.field2 = field2;
        notifyPropertyChanged(BR.field2);
        notifyPropertyChanged(BR.valid);
    }

    @Bindable
    public boolean isValid() {
        // 在这里进行字段验证逻辑，返回验证结果
        return !TextUtils.isEmpty(field1) && !TextUtils.isEmpty(field2);
    }
}

public class MainActivity extends AppCompatActivity {
    private MyViewModel viewModel;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ActivityMainBinding binding = DataBindingUtil.setContentView(this, R.layout.activity_main);
        viewModel = new MyViewModel();
        binding.setViewModel(viewModel);
    }
}