android 浏览器全屏展示

业务需求：浏览器设置中支持全屏显示的功能。?
分析：只需要在设置界面上增加是否全屏的checkBox，?然后BrowserActivity中读取这个值，?来设置窗口的Style.?
修改：?1.?修改项目下的res/xml文件夹下的browser_preferences.xml文件，?添加<CheckBoxPreference?
????????????????android:key="full_screen"?
????????????????android:defaultValue="false"?
????????????????android:title="@string/pref_full_screen"?
????????????????android:summary="@string/pref_full_screen_summary"?/>?
???????2.?BrowserActivity中创建SetScreen()方法?
????public?void?setScreen(){?
//set?to?full?screen?if?necessary?
SharedPreferences?sp?=?getSharedPreferences(this.getPackageName()+"_preferences",?
Context.MODE_WORLD_READABLE);?

boolean?isFullScreen?=?sp.getBoolean(BrowserSettings.PREF_FULL_SCREEN,?false);?
????????//if?search?dialog?is?open,?we?should?quit?full?screen.?
if(isFullScreen?&&?!isSearchDialogOpen){?
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);?
????????getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);?
}else{?
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);?
????????getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);?
}?
}?
如果我们第一次进入浏览器是非全屏，?然后进入设置修改成全屏模式，?这时候返回到BrowserActivity，?全屏模式必须马上切换过来。?所以我们在OnResume()里面调用setScreen()，?不要在onCreate()里面调.?
3.?大家可能注意到了，?判断全屏切换时有个isSearchDialogOpen变量，?这是用来控制在搜索框出现时的全屏切换的。?因为点击进地址栏时会调用系统的搜索框控件，?而这个控件不属于浏览器，?是个单独的窗口，?并且一开始创建时是有标题栏的。这时候如果设置成无标题栏的风格时，?就会出现标题栏先出现，?然后又隐藏上去，?并且有2-3次反复的情况，用户体验非常糟糕。?这里就做了个折中，?当搜索框出现时，?切换成非全屏模式，?这样标题栏就一直在那里，不会来回闪了。?退出搜索时，如果设置的是全屏，再切换成全屏模式。?所以在搜索框出现和消失时的代码部分，?还要做相应修改。?见如下代码：?
public?void?startSearch(String?initialQuery,?boolean?selectInitialQuery,?
Bundle?appSearchData,?boolean?globalSearch)?{?
if?(appSearchData?==?null)?{?
appSearchData?=?createGoogleSearchSourceBundle(GOOGLE_SEARCH_SOURCE_TYPE);?
}?

SearchEngine?searchEngine?=?mSettings.getSearchEngine();?
if?(searchEngine?!=?null?&&?!searchEngine.supportsVoiceSearch())?{?
//appSearchData.putBoolean(SearchManager.DISABLE_VOICE_SEARCH,?true);?
}?

//show?status?bar?when?search?window?pops?up.?isSearchDialogOpen?=?true;?

//show?status?bar?when?search?window?pops?up.?getWindow().addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);?
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);?

super.startSearch(initialQuery,?selectInitialQuery,?appSearchData,?globalSearch);?
}?

搜索框消失部分：?
//switch?to?full?screen?if?necessary?when?search?window?disappears.?
public?void?onDismiss()?{?
isSearchDialogOpen?=?false;?
setScreen();?
}?
（PS:?BrowserActivity必须继承OnDismissListener接口才有onDismiss方法。）?