原生动态化探讨

#define Dylib_PATH  "/System/Library/PrivateFrameworks/xxxxx/xxxxx/xxxxx"

- (void)dynamicLibraryLoad
{ 
  // dlopen 去动态加载 dylib
  void *kit = dlopen(Dylib_PATH,RTLD_LAZY);   
  
  // 在运行期动态加载的dylib应该如何调用里面的代码？  OC有运行时与反射
  
  Class pacteraClass = NSClassFromString(@"DynamicOpenMenth");
  if (!pacteraClass) {
      NSLog(@"Unable to get TestDylib class");
      return;
  }
  NSObject *pacteraObject = [pacteraClass new];
  [pacteraObject performSelector:@selector(startWithObject:withBundle:) withObject:self withObject:frameworkBundle];

  // 只有OC的代码才能动态调用么？C代码一样有办法 dlsym 通过函数符号获取动态加载后的函数地址，进行调用
  
  NSString *imsi = nil;
  int (*CTSIMSupportCopyMobileSubscriberIdentity)() = dlsym(kit, "CTSIMSupportCopyMobileSubscriberIdentity");
  imsi = (NSString*)CTSIMSupportCopyMobileSubscriberIdentity(nil);
  
  // 卸载动态库
  dlclose(kit);
}

- (id)initWithHtml:(NSString*)html withData:(NSString*)data andDelegate:(id)delegate andFallbackDelegate:(id)fallbackDelegate andOption:(long)option docName:(NSString *)docName {
    
    self = [super init];
    
    // 一大堆 property 对象的 初始化
    self.xxx = xxx;
    self.xxx = xx;
  	// 等等...
    
    //主要是 fb_node.c 对象，每个node 就是一个dom节点，需要计算整体布局就递归调用 layout.c 的算法
    if (!_core) {
        //构建排版内核对象
        _core = fb_core_new(); 
        //设置布局计算完毕后的回掉
        _core->core_layout_notify = core_layout_notify; 
        //设置 meta 信息处理的外部回掉
        _core->tpl_content_handler = platform_content_handler;
      	//设置整个 Dom 处理完毕后的回掉
        _core->core_load_finish_notify = core_load_finish_notify;
        //保存当前 Document 对象指针给 core ，便于 core 的一些处理
        _core->context = (__bridge void *)(self);
        
    }
    // 开始加载 模板 
    // - 传入数据 json 形态的 dom 数据（html参数）
    // - 传入数据 json 形态的 data 数据（data参数）
    fb_core_load_l(_core, [html UTF8String], [data UTF8String], false, option);
    return self;
}

bool fb_core_load_l(fb_core_t* core,
                  const char *page,
                  const char *data,
                  bool js_debuggable,
                  const long flags) {
  
    // ... 省略部分代码
  
		// 解析传入的 data json 数据
    if (data != NULL) {
        core->last_data = fbJSON_Parse(data);
    }
  
    // ... 省略部分代码
  
	  // 解析传入的 html json 数据
    core->html = fb_parser_json(core, page);

    // ... 省略部分代码

    // html 解析结果里面分拆出 body 与 head
    core->head = fb_node_by_tag(core->html, FB_tag_head);
    core->body = fb_node_by_tag(core->html, FB_tag_body);

    // ... 省略部分代码

    //### 如果head或者body为空，那么就无法正常渲染了，直接返回失败
    if (!core->head || !core->body) {
        return false;
    }

    // ... 省略部分代码
  
    //无 js 的鸟巢业务，即精简模式下不构建 js 虚拟机，非精简模式，构建 js 虚拟机上下文
    if (!core->isLiteMode) {
        fb_core_init_script_engine(core);
    }
  
    // ... 省略部分代码

  	// 非精简模式下，遍历 data  body  head 中的 script 标签数据，读取出js代码，输入 duktape 虚拟机上下文
    if (!core->isLiteMode) {
        const bool dataIsJson = fb_tools_is_json(data);
        fb_script_execute_string_l(core->scriptEngine, data, flags);
        
        for (int i = 0; i < core->head->cssNode.children_count; i++) {
            fb_node_t *node = core->head->subNodes[i];
            if (node->tag == FB_tag_script) {
                
                const char *src = fb_node_get_attr(node, "src");
                if (src) {
                    char *data = fb_platform_load_file(node->core, src);
                    fb_script_execute_string(core->scriptEngine, data);
                    if (data && strlen(data) != 0) {
                        free(data);
                    }
                }
                
                const char *text = fb_node_get_attr(node, "text");
                if (text) {
                    fb_script_execute_string(core->scriptEngine, text);
                }
            }
        }

        // ... 省略部分代码        
      
        //查看整个节点中是否包含 js 的 onload 事件，如果有则执行 onload
        fb_script_cb_t *onload = fb_node_get_event(core->body, "onload");
        if (onload) {
            fb_script_execute(core->scriptEngine, onload, NULL);
        }
        
        //查看整个节点中是否包含 js 的 onreload 事件，如果有则执行 onreload
        if (data && dataIsJson) {
            fb_script_cb_t *onreload = fb_node_get_event(core->body, "onreload");
            if (onreload && data) {
                core->hasOnReload = true;
                fb_script_execute_javascript_with_json(core->scriptEngine,
                                                       onreload->js_callback,
                                                       data);
            }
        }
    }

    // ... 省略部分代码 
  
    //### 最终layout一次，递归整个树，让每个 dom（即 node 节点对象，都经过layout.c的算法计算好了frame）
    fb_core_layout(core);
  
    // ... 省略部分代码 

    // 发送 Document Load Finish 回掉，触发后续的渲染流程
    if (core->core_load_finish_notify) {
        core->core_load_finish_notify(core);
    }

    return true;
}

- (void)updateLayout
{
    //循环指令队列，执行每个指令
    for (int i = 0; i < _core->actionSeq->length; ++i) {
        // ... 省略部分代码 
        
        //### 指令已经无效，跳过
        if (op->node == NULL) {
            continue;
        }
        
        //判断指令类型
        switch (op->op) {
                
            //### 创建view
            case DOM_CREATE: {

                FBView *view = nil;
                
                //创建 root View
                if (op->node->tag == FB_tag_body) {
                    
                    _root = [[FBView alloc] initWithNode:_core->body
                                                withDocument:self
                                                  withView:nil];
                    
                    view = _root;
                }
                else {
                    // 创建其他嵌入 View
                    // 识别子View 的native ui 类型
                    switch (op->node->tag) {
                    
                        // ... 省略部分代码 
                        
                        //容器空 View
                        case FB_tag_div: {
                            view = [[FBView alloc] initWithNode:op->node
                                                   withDocument:self
                                                       withView:nil];
                            break;
                        }
                        
                        // ... 省略部分代码 
                        
                        //原生勾选框 View
                        case FB_tag_checkbox: {
                            view = [[FBCheckbox alloc] initWithNode:op->node
                                                       withDocument:self
                                                           withView:nil];
                            break;
                        }
                        
                        // ... 省略部分代码 
                        
                        //原生开关 View
                        case FB_tag_switch: {
                            view = [[FBSwitch alloc] initWithNode:op->node
                                                       withDocument:self
                                                           withView:nil];
                            break;
                        }
                        // ... 省略部分代码 
                        
                        //原生文本标签 View
                        case FB_tag_label: {
                            
                            NSString *key = [NSString stringWithFormat:@"%llx", (long long)op->node];
                            view = [self.dictLabel objectForKey:key];
                            if (view == nil) {
                                view = [[FBLabel alloc] initWithNode:op->node
                                                        withDocument:self
                                                            withView:nil];
                                
                                [self.dictLabel setObject:view forKey:key];
                            } else {
                                [view associateNode:op->node];
                            }
                            break;
                        }
                        // ... 省略部分代码 
                        
                        //原生图片 View
                        case FB_tag_img: {
                            
                            NSString *key = [NSString stringWithFormat:@"%llx", (long long)op->node];
                            view = [self.dictImg objectForKey:key];
                            if (view == nil) {
                                view = [[FBImg alloc] initWithNode:op->node
                                                        withDocument:self
                                                            withView:nil];
                                
                                [self.dictImg setObject:view forKey:key];
                            } else {
                                [view associateNode:op->node];
                            }
                            
                            break;
                        }
                        // ... 省略部分代码 
                        
                        //原生按钮 View
                        case FB_tag_button: {
                            view = [[FBButton alloc] initWithNode:op->node
                                                  withDocument:self
                                                      withView:nil];
                            break;
                        }
                        
                        // 可以横向扩展各种原生 View
                        
                        // ... 省略部分代码 
                        
                        default: {
                            
                            break;
                        }
                    }
                }
                
                // ... 省略部分代码 

                break;
            }
                
            // 把一个 View add 到另一个View 成为子 View
            case DOM_ADDVIEW: {
                FBView *subView = [self findViewByNode:op->node];
                FBView *superView = [self findViewByNode:op->node->superNode];
                
                if (superView && subView) {
                    [superView addSubview:subView];
                }
                else {
                    //assert(false);
                }
                break;
            }
                
            // 删除一个 View
            case DOM_DELETEVIEW: {
                FBView *subView = [self findViewByNode:op->node];
                [subView removeFromSuperview];
                
                //### label 需要从 cache中移除
                unsigned tag = op->tag;
                if (tag == FB_tag_label) {
                    NSString *key = [NSString stringWithFormat:@"%llx", (long long)op->node];
                    [self.dictLabel removeObjectForKey:key];
                }
                
                //### img 需要从 cache中移除
                if (tag == FB_tag_img) {
                    NSString *key = [NSString stringWithFormat:@"%llx", (long long)op->node];
                    [self.dictImg removeObjectForKey:key];
                }

                [self removeView:op->node fbView:subView];
                
                break;
            }

            //### 更新 view 的 rect，rect 来自 layout.c 的计算结果
            case DOM_UPDATE_RECT: {
                FBView *view = [self findViewByNode:op->node];
                [view updateRect];
                break;
            }
                
            //### 更新 view 的其他 css属性
            case DOM_UPDATE_CSS: {
                FBView *view = [self findViewByNode:op->node];
                
                NSString *style = [NSString stringWithUTF8String:(char*)op->param];
                NSArray *arrKeyAndValue = [style componentsSeparatedByString:PARAM_DELIMITER_OC];
                if (arrKeyAndValue.count == 2) {
                    NSString *key = [arrKeyAndValue objectAtIndex:0];
                    NSString *value = [arrKeyAndValue objectAtIndex:1];
                    [view updateCSS:key withValue:value];
                }
                break;
            }
         
            //部分View 的native属性，比如字体粗细，比如背景色，需要进行设置
            case DOM_UPDATE_ATTR: {
                FBView *view = [self findViewByNode:op->node];

                NSString *style = [NSString stringWithUTF8String:(char*)op->param];
                NSArray *arrKeyAndValue = [style componentsSeparatedByString:PARAM_DELIMITER_OC];
                if (arrKeyAndValue.count == 2) {
                    NSString *key = [arrKeyAndValue objectAtIndex:0];
                    NSString *value = [arrKeyAndValue objectAtIndex:1];
                    [view updateAttr:key withValue:value];
                }
                break;
            }
                
            //部分 View 可以接受交互事件，比如点击事件 onClick，需要把原生的点击事件，与点击事件响应的js 绑定起来
            //因此这个 action 用于绑定 js 函数给 native 的点击事件 
            case DOM_UPDATE_EVENT: {
                FBView *view = [self findViewByNode:op->node];
                
                NSString *style = [NSString stringWithUTF8String:(char*)op->param];
                NSArray *arrKeyAndValue = [style componentsSeparatedByString:PARAM_DELIMITER_OC];
                if (arrKeyAndValue.count == 2) {
                    NSString *key = [arrKeyAndValue objectAtIndex:0];
                    NSString *value = [arrKeyAndValue objectAtIndex:1];
                    [view updateEvent:key withValue:value];
                }

                break;
            }
                
            //部分 View 可以接受 JS 代码控制，提供给 JS Native 方法可以调用
            //因此这个 action 用于绑定 native 方法给 js
            case DOM_UPDATE_FUNC: {
                FBView *view = [self findViewByNode:op->node];
                
                [view updateFunc:[NSString stringWithUTF8String:(char*)op->param] withValue:PARAM_DELIMITER_OC];
            }

            default:
                break;
        }
        
        // ... 省略部分代码 
    }
    
    // ... 省略部分代码 
}

- (void)updateEvent:(NSString*)key withValue:(NSString*)value;
- (void)updateFunc:(NSString*)key withValue:(NSString*)value;

- (void)updateEvent:(NSString *)key withValue:(NSString *)value
{
    if ([value isEqualToString:@"onclick"]) {
        [self.view setUserInteractionEnabled:YES];
        if (_tapRecognizer == nil) {
            _tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(onClicked:)];
            [self.view addGestureRecognizer:_tapRecognizer];
            const fb_node_t *fbNode = [self getFbNode];
            if (fbNode != nil && fbNode->_id != NULL) {
                NSString *seed = [[NSString alloc] initWithUTF8String:[self getFbNode]->_id];
                SEL selector = @selector(setActionName:);
                if ([_tapRecognizer respondsToSelector:selector]) {
                    [_tapRecognizer performSelector:selector withObject:seed];
                }
            }
        }
    }
}

- (void)onClicked:(id)sender
{
    if (_imageView)
        self.doc.focusView = _imageView;

    fb_platform_onclick([self getFbNode]);
}

- (void)updateFunc:(NSString*)key withValue:(NSString*)value {

    if ([key isEqualToString:@"focus"]) {

        [_textfield becomeFirstResponder];
    }
    else if ([key isEqualToString:@"blur"]) {

        [_textfield resignFirstResponder];
    }
    else {
        [super updateFunc:key withValue:value];
    }
}