MGJRouter源码解析
MGJRouter是实现iOS组件间交互的工具之一，路由的使用降低了不同模块之间的耦合度，提高代码的复用率以及不同模块间重组的灵活度，下面我就针对MGJRouter说一下自己的理解：
注册
routes主要用于存储已经注册过的路径及block
@property (nonatomic) NSMutableDictionary *routes;
下面三个方法是注册时对URL进行递归遍历以及对block进行存储
- (void)addURLPattern:(NSString *)URLPattern andHandler:(MGJRouterHandler)handler
{
//解析当前 URL 并转化出字典存贮在self.routes中
NSMutableDictionary *subRoutes = [self addURLPattern:URLPattern];
//将block存入到字典中
if (handler && subRoutes) {
subRoutes[@"_"] = [handler copy];
}
}
- (void)addURLPattern:(NSString *)URLPattern andObjectHandler:(MGJRouterObjectHandler)handler
{
NSMutableDictionary *subRoutes = [self addURLPattern:URLPattern];
if (handler && subRoutes) {
subRoutes[@"_"] = [handler copy];
}
}
- (NSMutableDictionary *)addURLPattern:(NSString *)URLPattern
{
//拆分当前URL
NSArray *pathComponents = [self pathComponentsFromURL:URLPattern];
NSMutableDictionary* subRoutes = self.routes;
//进行轮循依次将component按照字典存入
for (NSString* pathComponent in pathComponents) {
//由于按照顺序存储所以先存入的生效，后面的将无法存入
if (![subRoutes objectForKey:pathComponent]) {
//依次生成字典存入上一层字典
subRoutes[pathComponent] = [[NSMutableDictionary alloc] init];
}
//依次将最里面的字典赋值给subRoutes
subRoutes = subRoutes[pathComponent];
}
//将最里层的字典返回
return subRoutes;
}
最终存储数据的格式如下，调用时会对其中的字典进行递归查找
{
LWT = {
Home = {
OtherViewController = {
"_" = "<__NSGlobalBlock__: 0x10c5b0168>";
};
SecondViewController = {
"_" = "<__NSGlobalBlock__: 0x10c5b0148>";
};
};
};
}
调用
调用时会将路径进行分解递归查找到对应的block，并将传递进来的参数进行存储
+ (void)openURL:(NSString *)URL
{
[self openURL:URL completion:nil];
}
+ (void)openURL:(NSString *)URL completion:(void (^)(id result))completion
{
[self openURL:URL withUserInfo:nil completion:completion];
}
+ (void)openURL:(NSString *)URL withUserInfo:(NSDictionary *)userInfo completion:(void (^)(id result))completion
{
URL = [URL stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSMutableDictionary *parameters = [[self sharedInstance] extractParametersFromURL:URL matchExactly:NO];
//遍历字典
[parameters enumerateKeysAndObjectsUsingBlock:^(id key, NSString *obj, BOOL *stop) {
if ([obj isKindOfClass:[NSString class]]) {
//读出
parameters[key] = [obj stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
}
}];
if (parameters) {
//取出block并根据请求进行回调
MGJRouterHandler handler = parameters[@"block"];
//将方法中的参数和block保存下来以便后期使用
if (completion) {
parameters[MGJRouterParameterCompletion] = completion;
}
if (userInfo) {
parameters[MGJRouterParameterUserInfo] = userInfo;
}
if (handler) {
//删除注册时的block并发起回调
[parameters removeObjectForKey:@"block"];
NSLog(@"开始调用Block");
handler(parameters);
}
}
}
路由注销
- (void)removeURLPattern:(NSString *)URLPattern
{
//URL分解
NSMutableArray *pathComponents = [NSMutableArray arrayWithArray:[self pathComponentsFromURL:URLPattern]];
// 只删除该 pattern 的最后一级
if (pathComponents.count >= 1) {
// 假如 URLPattern 为 a/b/c, components 就是 @"a.b.c" 正好可以作为 KVC 的 key
//获取数组拼接的key
NSString *components = [pathComponents componentsJoinedByString:@"."];
NSMutableDictionary *route = [self.routes valueForKeyPath:components];
if (route.count >= 1) {
//删除最后一个参数
NSString *lastComponent = [pathComponents lastObject];
[pathComponents removeLastObject];
// 有可能是根 key，这样就是 self.routes 了
route = self.routes;
//获取字典层级的倒数第二层字典并删除
if (pathComponents.count) {
NSString *componentsWithoutLast = [pathComponents componentsJoinedByString:@"."];
route = [self.routes valueForKeyPath:componentsWithoutLast];
}
[route removeObjectForKey:lastComponent];
}
}
}
路由判断
即根据路径获取相应的block，如果没有查找到则返回nil
//根据路径取出block
- (NSMutableDictionary *)extractParametersFromURL:(NSString *)url matchExactly:(BOOL)exactly
{
NSMutableDictionary* parameters = [NSMutableDictionary dictionary];
parameters[MGJRouterParameterURL] = url;
//获取路由中存储的路由集合
NSMutableDictionary* subRoutes = self.routes;
//传入地址的组件
NSArray* pathComponents = [self pathComponentsFromURL:url];
BOOL found = NO;
// borrowed from HHRouter(https://github.com/Huohua/HHRouter)
//遍历传入URL组件
for (NSString* pathComponent in pathComponents) {
// 对 key 进行排序，这样可以把 ~ 放到最后
NSArray *subRoutesKeys =[subRoutes.allKeys sortedArrayUsingComparator:^NSComparisonResult(NSString *obj1, NSString *obj2) {
return [obj1 compare:obj2];
}];
//遍历全部路由key值进行比对查找
for (NSString* key in subRoutesKeys) {
if ([key isEqualToString:pathComponent] || [key isEqualToString:MGJ_ROUTER_WILDCARD_CHARACTER]) {
found = YES;
//查找到后取出子字典继续遍历
subRoutes = subRoutes[key];
break;
} else if ([key hasPrefix:@":"]) { //判断字符串是否以:为前缀
found = YES;
subRoutes = subRoutes[key];
NSString *newKey = [key substringFromIndex:1];
NSString *newPathComponent = pathComponent;
// 再做一下特殊处理，比如 :id.html -> :id
if ([self.class checkIfContainsSpecialCharacter:key]) {
NSCharacterSet *specialCharacterSet = [NSCharacterSet characterSetWithCharactersInString:specialCharacters];
NSRange range = [key rangeOfCharacterFromSet:specialCharacterSet];
if (range.location != NSNotFound) {
// 把 pathComponent 后面的部分也去掉
newKey = [newKey substringToIndex:range.location - 1];
NSString *suffixToStrip = [key substringFromIndex:range.location];
newPathComponent = [newPathComponent stringByReplacingOccurrencesOfString:suffixToStrip withString:@""];
}
}
parameters[newKey] = newPathComponent;
break;
} else if (exactly) {
found = NO;
}
}
// 如果没有找到该 pathComponent 对应的 handler，则以上一层的 handler 作为 fallback
if (!found && !subRoutes[@"_"]) {
return nil;
}
}
// Extract Params From Query.
NSArray<NSURLQueryItem *> *queryItems = [[NSURLComponents alloc] initWithURL:[[NSURL alloc] initWithString:url] resolvingAgainstBaseURL:false].queryItems;
for (NSURLQueryItem *item in queryItems) {
parameters[item.name] = item.value;
}
//将block放入字典中返回
if (subRoutes[@"_"]) {
parameters[@"block"] = [subRoutes[@"_"] copy];
}
return parameters;
}
MGJRouter的使用
- 注册
//无参数的
[MGJRouter registerURLPattern:[self appendAnimUrl:@"SecondViewController"] toHandler:^(NSDictionary *routerParameters) {
NSLog(@"routerParameters[ViewController]:%@", routerParameters[@"ViewController"]); // halfrost
UINavigationController *navigationVC = routerParameters[MGJRouterParameterUserInfo][@"navigationVC"];
SecondController *vc = [[SecondController alloc] init];
[navigationVC pushViewController:vc animated:YES];
}];
//有参数无回调
[MGJRouter registerURLPattern:[self appendAnimUrl:@"OtherViewController"] toHandler:^(NSDictionary *routerParameters) {
UINavigationController *navigationVC = routerParameters[MGJRouterParameterUserInfo][@"navigationVC"];
NSString *labelText = routerParameters[MGJRouterParameterUserInfo][@"text"];
OtherViewController *vc = [[OtherViewController alloc] init];
vc.titleText = labelText;
[navigationVC pushViewController:vc animated:YES];
}];
//有参数有回调
[MGJRouter registerURLPattern:[self appendAnimUrl:@"ThridViewController"] toHandler:^(NSDictionary *routerParameters) {
UINavigationController *navigationVC = routerParameters[MGJRouterParameterUserInfo][@"navigationVC"];
void(^block)(NSString *) = routerParameters[MGJRouterParameterUserInfo][@"block"];
ThridViewController *vc = [[ThridViewController alloc] init];
vc.titleText = routerParameters[MGJRouterParameterUserInfo][@"text"];
vc.backBlock = block;
[navigationVC pushViewController:vc animated:YES];
}];
- 调用
由于是通过路径进行的查找相应的controller增加了大量的硬编码，直接通过MGJrouter的方法调用无疑会增加pushController中代码的复杂度，同时也提高了开发者之间沟通交流的成本，在这里通过对MGJrouter进行分类增加跳转方法以便降低模块间沟通的成本，同理注册的时候也可以对其增加分类以防止单个文件过重，并且在此处可以增加参数判断以防止传参丢失等情况的出现
#define Home_base_Url @"LWT://Home/:name"
+ (void)pushSecondCtl:(UINavigationController *)nav
{
[MGJRouter openURL:[MGJRouter generateURLWithPattern:Home_base_Url parameters:@[@"SecondViewController"]] withUserInfo:@{@"navigationVC":nav} completion:nil];
}
+ (void)pushOtherController:(UINavigationController *)nav title:(NSString *)titleText
{
[MGJRouter openURL:[MGJRouter generateURLWithPattern:Home_base_Url parameters:@[@"OtherViewController"]]
withUserInfo:@{@"navigationVC" : nav,
@"text": titleText,
}
completion:nil];
}
+ (void)pushThridController:(UINavigationController *)nav title:(NSString *)titleText block:(void (^)(NSString * result))block
{
[MGJRouter openURL:[MGJRouter generateURLWithPattern:Home_base_Url parameters:@[@"ThridViewController"]]
withUserInfo:@{@"navigationVC" : nav,
@"text": titleText,
@"block":block
}
completion:nil];
}
以上就是我对MGJrouter的理解及使用，如有不足欢迎补充