package com.example.week; import android.os.Bundle; import android.support.v4.app.FragmentActivity; import android.support.v7.app.AppCompatActivity; import android.widget.FrameLayout; import android.widget.RadioButton; import android.widget.RadioGroup; public class MainActivity extends FragmentActivity {
      private RadioGroup gr;     private RadioButton shouye;     private RadioButton xigua;     private RadioButton wei;     private RadioButton wode;     private FrameLayout zhan;     @Override     protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);         initView();         getSupportFragmentManager().beginTransaction().replace(R.id.zhan,new Fragment1()).commit();         gr.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
              @Override             public void onCheckedChanged(RadioGroup group, int checkedId) {
                  switch (checkedId){
                      case R.id.shouye:                         getSupportFragmentManager().beginTransaction().                                 replace(R.id.zhan,new Fragment1()).commit();                         break;                     case R.id.xigua:                         getSupportFragmentManager().beginTransaction().                                 replace(R.id.zhan, new Fragment2()).commit();                         break;                     case R.id.wei:                         getSupportFragmentManager().beginTransaction().                                 replace(R.id.zhan,new Fragment3()).commit();                         break;                     case R.id.wode:                         getSupportFragmentManager().beginTransaction().                                 replace(R.id.zhan,new Fragment4()).commit();                         break;                 }             }         });     }     private void initView() {
          gr = (RadioGroup) findViewById(R.id.gr);         shouye = (RadioButton) findViewById(R.id.shouye);         xigua = (RadioButton) findViewById(R.id.xigua);         wei = (RadioButton) findViewById(R.id.wei);         wode = (RadioButton) findViewById(R.id.wode);         zhan = (FrameLayout) findViewById(R.id.zhan);     } }