今天学习Fragment的时候，实例化继承Fragment的对象（RightFragment（）和RightFragment2（））的时候报错

Question

//这种错误只是在使用support-v4的时候出现，而使用android.app的时候就不会出错 //由于我使用的Android Studio 所以build.gradle中已经添加了appcompat-v7库的依赖 //会自动引入support-v4; package com.example.myapplication; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentTransaction; import android.support.v4.app.Fragment; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; public class MainActivity extends AppCompatActivity {     @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);         replaceFragment(new RightFragment());         //在实例化RightFragment()的时候报错         Button button = (Button)findViewById(R.id.button_1);         button.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View v) {                 switch (v.getId()) {                     case R.id.button_1;                                              replaceFragment(new RightFragment2());                         //在实例化RightFragment2()的时候报错                                                                           break;                     default:                         break;                 }             }         });     } //replaceFragment方法     private void replaceFragment(Fragment fragment){         FragmentManager fragmentManager = getSupportFragmentManager();         FragmentTransaction transaction = fragmentManager.beginTransaction();         transaction.replace(R.id.right_fragment,fragment);         transaction.commit();     } }由于是新手有些地方可能错误可能很明显还请口下留情

Answer 1

把activity的继承父类换成FragmentActivity试试