切换片段时活动崩溃

Question

我有一个带有列表视图和按钮的活动，当单击按钮时，我添加了一个片段。我的问题是，当我在片段中滚动然后关闭片段时，活动中的列表视图也会滚动，当我单击按钮将片段带回应用程序崩溃时。有什么帮助吗？

主要活动代码

     public class MainActivity extends Activity implements OnClickListener  {
 ListView listView ;
 Button B;
 FragmentTransaction fragmentTransaction;
 FragmentManager fragmentManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
      fragmentManager = getFragmentManager();
     fragmentTransaction = fragmentManager.beginTransaction();
     listView = (ListView) findViewById(R.id.list);

     // Defined Array values to show in ListView
      String[] values = new String[] { "1", 
                                      "2",
                                      "3",
                                      "4", 
                                      "5", 
                                      "6", 
                                      "7", 
                                      "8",
                                      "9",
                                      "10",
                                      "11",
                                      "12",
                                      "13",
                                      "14",
                                      "15",
                                      "16",
                                      "17",
                                      "18",
                                      "19",
                                      "20",
                                      "21",
                                      "22",
                                      "23"



                                     };
     ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
             android.R.layout.simple_list_item_1, android.R.id.text1, values);


           // Assign adapter to ListView
           listView.setAdapter(adapter); 
    B=(Button)findViewById(R.id.button1);
    B.setOnClickListener(this);
}

   @Override
   public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub


    switch(v.getId())
    {
         case R.id.button1:
             Second s = new Second();

             fragmentTransaction.add(android.R.id.content, s);

              fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
             fragmentTransaction.addToBackStack("Cam");
             fragmentTransaction.commit();
         break;





    }


   }

   }

Answer 1

试试这个::

从onCreate(...){...} 方法中删除第一个fragmentManager = getFragmentManager(); fragmentTransaction = fragmentManager.beginTransaction();

并将此代码放在该案例上，即，

    @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub


    switch(v.getId())
    {
         case R.id.button1:
             Second s = new Second();
             fragmentManager = getFragmentManager();
             fragmentTransaction = fragmentManager.beginTransaction();
             fragmentTransaction.add(android.R.id.content, s);

              fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
             fragmentTransaction.addToBackStack("Cam");
             fragmentTransaction.commit();
         break;
    }

   }

Answer 2

将此添加到以下内容：

 switch(v.getId())
    {
         case R.id.button1:
             Second s = new Second();
             //add this
             fragmentTransaction = fragmentManager.beginTransaction();  
             fragmentTransaction.replace(android.R.id.content, s);
             fragmentTransaction.addToBackStack(null);
             fragmentTransaction.commit();
         break;

    }