获取LayoutInflater有三种不同的方式,那么这三种方式有什么区别呢?
源码:
① LayoutInflater inflater = LayoutInflater.from(context);
(LayoutInflater类)
<span style="font-size:14px;">public static LayoutInflater from(Context context) { LayoutInflater LayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); if (LayoutInflater == null) { throw new AssertionError("LayoutInflater not found."); } return LayoutInflater; }</span>
② LayoutInflater inflater
= getLayoutInflater();(Activity类)
<span style="font-size:14px;color:#330033;">public LayoutInflater getLayoutInflater() { return getWindow().getLayoutInflater(); }</span>
public PhoneWindow(Context context) { super(context); mLayoutInflater = LayoutInflater.from(context); }
③ LayoutInflater
inflater =(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);(Activity类)
<span style="font-size:14px;color:#330033;"> public static final String LAYOUT_INFLATER_SERVICE = "layout_inflater";</span>
ps:
Use with
togetSystemService(java.lang.String)
retrieve a
forandroid.view.LayoutInflater
inflating layout resources in this context.
从源码上,三种方式在本质都是一样的,②是调用①的方法,而①则是在调用③。java很有意思就是这样子调来调去,给人一种似是而非的感觉。
对于getSystemService类,我们在源码中可以看到提供了很多的Service:
WINDOW_SERVICE (WindowManager) 管理打开的窗口程序
LAYOUT_INFLATER_SERVICE (LayoutInflater) 取得xml里定义的view
ACTIVITY_SERVICE (ActivityManager)
管理应用程序的系统状态
POWER_SERVICE (PowerManger)
电源的服务
ALARM_SERVICE (AlarmManager)
闹钟的服务
NOTIFICATION_SERVICE (NotificationManager)状态栏的服务
KEYGUARD_SERVICE (KeyguardManager)
键盘锁的服务
LOCATION_SERVICE (LocationManager)
位置的服务
SEARCH_SERVICE (SearchManager)
搜索的服务
VEBRATOR_SERVICE (Vebrator)
手机震动的服务
CONNECTIVITY_SERVICE (Connectivity)
网络连接的服务
WIFI_SERVICE (WifiManager)
WiFi服务
TELEPHONY_SERVICE (TeleponyManager)
电话服务
未完待续