寒假学干货之------ 初学者关于fragment_main（碎片的困扰）

我们在activity_main中编写的框架，会被fragment_main中的取代掉，是因为新版的ADT为了配合平板Android3.0开发

起作用的代码在MainActivity.java中

 package com.myprogram.text_two;

 import android.support.v7.app.ActionBarActivity;
 import android.support.v7.app.ActionBar;
 import android.support.v4.app.Fragment;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
 import android.os.Build;

 public class MainActivity extends ActionBarActivity {

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);

         if (savedInstanceState == null) {
             getSupportFragmentManager().beginTransaction()
                     .add(R.id.container, new PlaceholderFragment())
                     .commit();
         }
     }

     @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 boolean onOptionsItemSelected(MenuItem item) {
         // Handle action bar item clicks here. The action bar will
         // automatically handle clicks on the Home/Up button, so long
         // as you specify a parent activity in AndroidManifest.xml.
         int id = item.getItemId();
         if (id == R.id.action_settings) {
             return true;
         }
         return super.onOptionsItemSelected(item);
     }

     /**
      * A placeholder fragment containing a simple view.
      */
     public static class PlaceholderFragment extends Fragment {

         public PlaceholderFragment() {
         }

         @Override
         public View onCreateView(LayoutInflater inflater, ViewGroup container,
                 Bundle savedInstanceState) {
             View rootView = inflater.inflate(R.layout.fragment_main, container, false);
             return rootView;
         }
     }

 }

中浅蓝色背景的，屏蔽掉即可