OnCheckedChangeListener问题

Question

package com.example.to; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.CompoundButton; import android.widget.ImageView; import android.widget.ToggleButton; public class MainActivity extends AppCompatActivity implements OnCheckedChangeListener{     /**      * 初始化      * */     private ImageView ima;     private ToggleButton tb;     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);         tb = (ToggleButton) findViewById(R.id.toggleButton);         ima = (ImageView) findViewById(R.id.imageView;         tb.setOnCheckedChangeListener(this);     }     @Override     public void OnCheckedChanged(CompoundButton buttonView, boolean isChecked){         ima.setBackground(isChecked?R.drawable.OFF:R.drawable.ON);     } }OnCheckedChangeListenerOnCheckedChangeListener有问题，一直报错。

Answer 1

应该是没有导包

import android.widget.CompoundButton.OnCheckedChangeListener;

Answer 2

implements CompoundButton.OnCheckedChangeListener

这样写试试

Answer 3

错误如上图