错误：OnCheckedChangeListener 无法解析为类型

Question

我在 setOnCheckedChangeListener 和 OnCheckedChangeListener 下有红线。错误消息告诉我：此行有多个标记 - OnCheckedChangedListener 无法解析为类型 - RadioGroup 类型中的方法 setOnCheckedChangedListener(RadioGroup.OnCheckedChangeListener) 不适用于参数 (new OnCheckedChangeListener(){})

package com.lifematters;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;

public class Test1 extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.test1);

    //define Navigation Image Buttons
    final Button nextBtn = (Button) findViewById(R.id.btnNext);



    RadioGroup radioGroup = (RadioGroup) findViewById(R.id.radioAnswers1);
    radioGroup.setOnCheckedChangeListener(new OnCheckedChangeListener()
    {
        public void onCheckedChanged (RadioGroup group, int checkedId){

        final RadioButton radioButton1 = (RadioButton) findViewById(R.id.radioA1);
        final RadioButton radioButton2 = (RadioButton) findViewById(R.id.radioA2);
        final RadioButton radioButton3 = (RadioButton) findViewById(R.id.radioA3);
        final RadioButton radioButton4 = (RadioButton) findViewById(R.id.radioA4);

        if (radioButton1.isChecked()) {
            DisplayToast("No, not at all");

        } else if (radioButton2.isChecked()) {
            DisplayToast("On some days");

        }else if (radioButton3.isChecked()) {
            DisplayToast("On more than half the days");

        }else {
            DisplayToast("Nearly everyday");
        }
    }

  });


  }

} 

Answer 1

两种可能性：

• 改成RadioGroup.OnCheckedChangeListener

• 将其添加到课程的开头：

  import android.widget.RadioGroup.OnCheckedChangeListener;
  

对于DisplayToast，添加以下内容：

public void displayToast(String text){
    Toast.makeText(this, text, Toast.Toast.LENGTH_SHORT).show();
}

并在您的代码中更改DisplayToast为。displayToast按照惯例，方法名称应以小写字母开头。只有类名应该以大写字母开头。