PDF阅读器-系统分享 2018-07-12

1. webView 直接加载:

• 核心代码如下

 if ([self.filePath hasPrefix:@"http"]) {
//网络文件
        [self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:self.filePath]]];
    }else if(self.filePath.length > 0){
        NSString * nameFile = self.filePath.lastPathComponent;
        if (self.title.length == 0) {
            self.title = nameFile;
        }
//本地文件
        [self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL fileURLWithPath:self.filePath]]];
    }

2. pageViewController 加载:

• 核心代码如下

    PDFItem_ViewController * vc1 = [self viewControllerAtIndex:0 current:-1];
    NSMutableArray *array = @[].mutableCopy;
    if (vc1) {
        [array addObject:vc1];
        [_visibleVCArray addObject:vc1];
    }
  
//设置初始化页面控制器
    [self setViewControllers:array.copy direction:UIPageViewControllerNavigationDirectionReverse animated:YES completion:^(BOOL finished) {
    }];


#pragma mark UIPageViewControllerDataSource
//翻页时候的前后控制器设置
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController{
    PDFItem_ViewController * itemVC = (PDFItem_ViewController *)viewController;
    NSInteger index = itemVC.pageIndex;
    index--;
    return [self viewControllerAtIndex:index current:itemVC.pageIndex];
}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController{
    PDFItem_ViewController * itemVC = (PDFItem_ViewController *)viewController;
    NSInteger index = itemVC.pageIndex;
    index ++;
    return [self viewControllerAtIndex:index current:itemVC.pageIndex];
}

//自定义方法：用于根据pageIndex 获取不同的控制器，这里采用复用的技术，类似tableView的cell ,觉得减少控制器的创建销毁，提示性能，减少能耗
- (PDFItem_ViewController *)viewControllerAtIndex:(NSUInteger)index current:(NSUInteger)currentIndex
{
    //Return the PDFViewController for the given index.
    if ((index > _pageTotal) ) {
        return nil;
    }
    PDFItem_ViewController *dataViewController = nil;
    //Create a new view controller and pass suitable data.
    if (self.visibleVCArray.count > 0) {
        for (PDFItem_ViewController *validVC in self.visibleVCArray) {
            if (validVC.pageIndex != currentIndex) {
                dataViewController = validVC;
                NSLog(@"复用了");
            }
        }
    }
    if (!dataViewController) {
        dataViewController = [[PDFItem_ViewController alloc]init];
        dataViewController.view.frame = self.view.bounds;
        [self.visibleVCArray addObject:dataViewController];
    }
    dataViewController.pageIndex = index;
//设置页面相应的渲染内容
    dataViewController.pageRef = CGPDFDocumentGetPage(_pdfRef, index+1);
    return dataViewController;
}

3. demo啦.hahahhahahahah