WeexSDK之注册Handlers

先看代码：

+ (void)_registerDefaultHandlers
{
    [self registerHandler:[WXResourceRequestHandlerDefaultImpl new] withProtocol:@protocol(WXResourceRequestHandler)];
    [self registerHandler:[WXNavigationDefaultImpl new] withProtocol:@protocol(WXNavigationProtocol)];
    [self registerHandler:[WXURLRewriteDefaultImpl new] withProtocol:@protocol(WXURLRewriteProtocol)];

}

WXSDKEngine中默认注册了3个Handler。

+ (void)registerHandler:(id)handler withProtocol:(Protocol *)protocol
{
    WXAssert(handler && protocol, @"Fail to register the handler, please check if the parameters are correct ！");

    [WXHandlerFactory registerHandler:handler withProtocol:protocol];
}

WXSDKEngine会继续调用WXHandlerFactory的registerHandler:withProtocol:方法。

@interface WXHandlerFactory : NSObject

@property (nonatomic, strong) WXThreadSafeMutableDictionary *handlers;

+ (void)registerHandler:(id)handler withProtocol:(Protocol *)protocol;

+ (id)handlerForProtocol:(Protocol *)protocol;

+ (NSDictionary *)handlerConfigs;

@end

WXHandlerFactory也是一个单例，里面有一个线程安全的字典handlers，用来保存实例和Protocol名的映射表。