2.抽取代码(BaseActivity)

1.抽取BaseActivity   管理所有activity 方便退出

public class BaseActivity extends ActionBarActivity {
	// 管理运行的所有的activity
	public final static List<BaseActivity> mActivities = new LinkedList<BaseActivity>();//增删快

	//使用广播也可以，如果当前Activity想退出可以，sendReceiver
//	private KillAllReceiver receiver;
//	private class KillAllReceiver extends BroadcastReceiver{
//
//		@Override
//		public void onReceive(Context context, Intent intent) {
//			finish();
//		}
//	}
	
	
	
	@Override 
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
//		receiver=new KillAllReceiver();
//		IntentFilter filter=new IntentFilter("com.itheima.google.killall");
//		registerReceiver(receiver, filter);
		
		//解决同步问题，不可以添加的时候删除
		synchronized (mActivities) {
			mActivities.add(this);
		}
		init();//定义几个方法子类去实现，代码不臃肿，这个是初始化view前的操作
		initView();
		initActionBar();
	}
	@Override
	protected void onDestroy() {
		super.onDestroy();
		synchronized (mActivities) {
			mActivities.remove(this);
		}
//		if(receiver!=null){
//			unregisterReceiver(receiver);
//			receiver=null;
//		}
	}

	public void killAll() {
		// 复制了一份mActivities 集合，因为不能在操作mActivities 的时候去遍历，就是这样复制的
		List<BaseActivity> copy;
		synchronized (mActivities) {
			copy = new LinkedList<BaseActivity>(mActivities);
		}
		for (BaseActivity activity : copy) {
			activity.finish();
		}
		// 杀死当前的进程
		android.os.Process.killProcess(android.os.Process.myPid());
	}
	protected void initActionBar() {
	}
	protected void initView() {
	}
	protected void init() {
	}
}

2.MainActivity

public class MainActivity extends BaseActivity implements
		OnQueryTextListener {
	private DrawerLayout mDrawerLayout;
	private ActionBarDrawerToggle drawerToggle;
	private ViewPager mViewPager;
	private PagerTabStrip pager_tab_strip;
	private String[] tab_names;  // 标签的名字
	@Override
	protected void initActionBar() {
		ActionBar actionBar = getSupportActionBar();
		actionBar.setDisplayHomeAsUpEnabled(true);
		actionBar.setHomeButtonEnabled(true);
		drawerToggle = new ActionBarDrawerToggle(this,
				mDrawerLayout, R.drawable.ic_drawer_am, R.string.open_drawer,
				R.string.close_drawer){

					@Override
					public void onDrawerClosed(View drawerView) {
						super.onDrawerClosed(drawerView);
						Toast.makeText(getApplicationContext(), "抽屉关闭了", 0).show();
					}
					@Override
					public void onDrawerOpened(View drawerView) {
						super.onDrawerOpened(drawerView);
						Toast.makeText(getApplicationContext(), "抽屉打开了", 0).show();
					}
			
		};
		mDrawerLayout.setDrawerListener(drawerToggle);
		//  让开关和actionbar建立关系 
		drawerToggle.syncState();
		
	}
	@Override
	protected void init() {
		tab_names = UiUtils.getStringArray(R.array.tab_names);
	}
	
	@Override
	protected void initView() {
		setContentView(R.layout.activity_main);
		mDrawerLayout = (DrawerLayout) findViewById(R.id.dl);
		mViewPager=(ViewPager) findViewById(R.id.vp);
		pager_tab_strip=(PagerTabStrip) findViewById(R.id.pager_tab_strip);
		//  设置标签下划线的颜色
		pager_tab_strip.setTabIndicatorColor(getResources().getColor(R.color.indicatorcolor));
		
		mViewPager.setAdapter(new MainAdpater(getSupportFragmentManager()));
		//sendBroadcast(new Intent("com.itheima.google.killall"));
		//Log.i(tag, msg)
	}

	private class MainAdpater extends FragmentStatePagerAdapter{
		public MainAdpater(FragmentManager fm) {
			super(fm);
		}
		// 每个条目返回的fragment
		//  0
		@Override
		public Fragment getItem(int position) {
			//  通过Fragment工厂  生产Fragment   
			return FragmentFactory.createFragment(position);
		}
		// 一共有几个条目 
		@Override
		public int getCount() {
			return tab_names.length;
		}
		// 返回每个条目的标题
		@Override
		public CharSequence getPageTitle(int position) {
			return tab_names[position];
		}
		
	}

	@SuppressLint("NewApi")
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		getMenuInflater().inflate(R.menu.activity_main, menu);
		// 如果运行的环境 (部署到什么版本的手机 )大于3.0
		if (android.os.Build.VERSION.SDK_INT > 11) {
			SearchView searchView = (SearchView) menu.findItem(
					R.id.action_search).getActionView();
			searchView.setOnQueryTextListener(this);// 搜索的监听
		} 
		return true;
	}

	
	/** 处理actionBar菜单条目的点击事件 */
	public boolean onOptionsItemSelected(MenuItem item) {
		if (item.getItemId() == R.id.action_search) {
			Toast.makeText(getApplicationContext(), "搜索", 0).show();
		}
		return drawerToggle.onOptionsItemSelected(item)|super.onOptionsItemSelected(item);
	}

	// 当搜索提交的时候
	@Override
	public boolean onQueryTextSubmit(String query) {
		Toast.makeText(getApplicationContext(), query, 0).show();
		return true;
	}
	// 当搜索的文本发生变化
	@Override
	public boolean onQueryTextChange(String newText) {
		return true;
	}
}

3.UiUtils

public class UiUtils {
	/**
	 * 获取到字符数组 
	 * @param tabNames  字符数组的id
	 */
	public static String[] getStringArray(int tabNames) {
		return getResource().getStringArray(tabNames);
	}

	public static Resources getResource() {
		return BaseApplication.getApplication().getResources();
	}
	
	/** dip转换px */
	public static int dip2px(int dip) {
		final float scale = getResource().getDisplayMetrics().density;
		return (int) (dip * scale + 0.5f);
	}

	/** pxz转换dip */

	public static int px2dip(int px) {
		final float scale = getResource().getDisplayMetrics().density;
		return (int) (px / scale + 0.5f);
	}
}

这样定义数组：string.xml里

<string-array name="tab_names">
        <item>首页</item>
        <item>应用</item>
        <item>游戏</item>
        <item>专题</item>
        <item>分类</item>
        <item>排行</item>
    </string-array>

4.FragmentFactory

public class FragmentFactory {

	private static Map<Integer, Fragment> mFragments = new HashMap<Integer, Fragment>();

	public static Fragment createFragment(int position) {
		Fragment fragment = null;
		fragment = mFragments.get(position);  //在集合中取出来Fragment
		if (fragment == null) {  //如果再集合中没有取出来 需要重新创建
			if (position == 0) {
				fragment = new HomeFragment();
			} else if (position == 1) {
				fragment = new AppFragment();
			} else if (position == 2) {
				fragment = new GameFragment();
			} else if (position == 3) {
				fragment = new SubjectFragment();
			} else if (position == 4) {
				fragment = new CategoryFragment();
			} else if (position == 5) {
				fragment = new TopFragment();
			}
			if (fragment != null) {
				mFragments.put(position, fragment);// 把创建好的Fragment存放到集合中缓存起来
			}
		}
		return fragment;

	}
}

通过这样获取上下文，就不需要在createFragment里把content参数里传进去了，当然需要在清单文件里写name

/**
 * 代表当前应用程序
 * @author itcast
 *
 */
public class BaseApplication extends Application {
	private static BaseApplication application;
	@Override
	public void onCreate() {
		super.onCreate();
		application=this;
		
	}
	public static Context getApplication() {
		return application;
	}
}

来自为知笔记(Wiz)