android 新建项目中去掉标题栏

1.新建new android application project

theme选none 并打钩创建一个Blank Activity

运行如下图所示：

2。若想把标题栏去掉，更改Manifestr的MainActivity 主题样式

>styles.xml中改

开始将<style name="AppTheme" parent="AppBaseTheme">

改为：<style name="AppTheme" parent="android:Theme.Light.NoTitleBar">//无标题白色背景

去行，闪退并报错：Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.

3。原因，是由于public class MainActivity extends ActionBarActivity在创建的时候继承了ActionBarActivity有标题的类，这样就会报错

更改继承FragmentActivity并把相应提示报错处理一下就可以。

具体代码如下：

 package com.example.abc;

 import android.support.v7.app.ActionBarActivity;
 import android.support.v7.app.ActionBar;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentActivity;
 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 FragmentActivity {

     @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;
         }
     }

 }

运行正确：