void是此变量的无效类型

我收到此错误：

void是变量onRadioButtonClicked的无效类型

但开发者网站说虚空是必须的！ 那问题出在哪里？ xml的编码是正确的。问题必须在这里：

package com.example.kernel.version; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.support.v4.app.NavUtils; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Button; import android.widget.RadioButton; public class MainPage extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Intent intent=getIntent(); setContentView(R.layout.activity_main_page); public void onRadioButtonClicked(View view) { // Is the button now checked? boolean checked = ((RadioButton) view).isChecked(); // Check which radio button was clicked switch(view.getId()) { case R.id.radio_pirates: if (checked) // Pirates are the best break; case R.id.radio_ninjas: if (checked) // Ninjas rule break; } } 

Answer 1

您的onRadioButtonClicked包含在您的onCreate方法中 – 使它们成为单独的方法。 之后添加一个右括号} ：

 setContentView(R.layout.activity_main_page); 

Answer 2

像这样做：

 import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.support.v4.app.NavUtils; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Button; import android.widget.RadioButton; public class MainPage extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Intent intent=getIntent(); setContentView(R.layout.activity_main_page); } public void onRadioButtonClicked(View view) { // Is the button now checked? boolean checked = ((RadioButton) view).isChecked(); // Check which radio button was clicked switch(view.getId()) { case R.id.radio_pirates: if (checked) // Pirates are the best break; case R.id.radio_ninjas: if (checked) // Ninjas rule break; } } }