Android-LayoutInflater
/**
获取LayoutInflater服务.
* Obtains the LayoutInflater from the given context.
*/
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;
}
public abstract class Context 抽象类.
public abstract Object getSystemService(String name);
【ContextImpl.java】
class ContextImpl extends Context { 实现类
@Override
public Object getSystemService(String name) {
ServiceFetcher fetcher = SYSTEM_SERVICE_MAP.get(name);
return fetcher == null ? null : fetcher.getService(this);
}
// 注册服务.
static {
registerService(ACCESSIBILITY_SERVICE, new ServiceFetcher() {
public Object getService(ContextImpl ctx) {
return AccessibilityManager.getInstance(ctx);
}});
registerService(CAPTIONING_SERVICE, new ServiceFetcher() {
public Object getService(ContextImpl ctx) {
return new CaptioningManager(ctx);
}});
registerService(ACCOUNT_SERVICE, new ServiceFetcher() {
public Object createService(ContextImpl ctx) {
IBinder b = ServiceManager.getService(ACCOUNT_SERVICE);
IAccountManager service = IAccountManager.Stub.asInterface(b);
return new AccountManager(ctx, service);
}});
... ...
registerService(KEYGUARD_SERVICE, new ServiceFetcher() {
public Object getService(ContextImpl ctx) {
// TODO: why isn't this caching it? It wasn't
// before, so I'm preserving the old behavior and
// using getService(), instead of createService()
// which would do the caching.
return new KeyguardManager();
}});
// LAYOUT_INFLATER_SERVICE 服务.
registerService(LAYOUT_INFLATER_SERVICE, new ServiceFetcher() {
public Object createService(ContextImpl ctx) {
return PolicyManager.makeNewLayoutInflater(ctx.getOuterContext());
}});
registerService(LOCATION_SERVICE, new ServiceFetcher() {
public Object createService(ContextImpl ctx) {
IBinder b = ServiceManager.getService(LOCATION_SERVICE);
return new LocationManager(ctx, ILocationManager.Stub.asInterface(b));
}});
registerService(NETWORK_POLICY_SERVICE, new ServiceFetcher() {
@Override
public Object createService(ContextImpl ctx) {
return new NetworkPolicyManager(INetworkPolicyManager.Stub.asInterface(
ServiceManager.getService(NETWORK_POLICY_SERVICE)));
}
});
... ...