需求：检查本地是否有需要查看的PDF文件，没有即下载缓存到本地(base64转码)，有则直接使用原生QLPreviewController打开，常规缓存方案。
YJPDFTools
/**
* IsExist 判断是否本地存在
*/
//IsExist
- (BOOL)isExistPdfFileWithBase:(UIViewController *)superVC file:(NSString *)fileName{
//HomeDirectory
NSString *documentsDirectory = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];
NSFileManager *fileManager = [NSFileManager defaultManager];
//DocumentsName
NSString *filePaths = [documentsDirectory stringByAppendingPathComponent:@"PdfDocuments"];
if (![fileManager fileExistsAtPath:filePaths]) {
[fileManager createDirectoryAtPath:filePaths withIntermediateDirectories:YES attributes:nil error:nil];
return NO;
}
//FileName
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"PdfDocuments/%@",fileName]];
if(![fileManager fileExistsAtPath:filePath]) {
//Return To Download File
return false;
} else{
//OpenLocalFile
YJPDFReaderVC *readerVC = [YJPDFReaderVC new];
readerVC.title = fileName;
[readerVC setQLPreViewMethodWith:filePath];
[superVC.navigationController pushViewController:readerVC animated:true];
return true;
}
}
/**
* Write 写入下载的PDF文件
*/
- (void)writeFileWith:(NSDictionary *)data completeBlock:(void(^)(void))completionHandler{
NSDictionary *dataDic = data;
NSString *fileName = [dataDic objectForKey:@"file_name"];
NSString *base64String = [dataDic objectForKey:@"base64"];
NSData *dataData = [[NSData alloc]initWithBase64EncodedString:base64String options:NSDataBase64DecodingIgnoreUnknownCharacters];
NSString *documentsPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
NSString *strPath = [documentsPath stringByAppendingPathComponent:[NSString stringWithFormat:@"PdfDocuments/%@",fileName]];
if ([dataData writeToFile:strPath atomically:YES]) {
completionHandler();
}
}
PDFReader
/**
* 预览PDF文件
* urlSting:文件路径
*/
- (void)setQLPreViewMethodWith:(NSString *)urlString{
self.pdfUrl = [NSURL fileURLWithPath:urlString];
[self addChildViewController:self.qlpreView];
[self.view addSubview:self.qlpreView.view];
}
#pragma mark - Delegate
#pragma mark - 返回文件的个数
- (NSInteger)numberOfPreviewItemsInPreviewController:(QLPreviewController *)controller {
return 1;
}
#pragma mark - 即将要退出浏览文件时执行此方法
- (void)previewControllerWillDismiss:(QLPreviewController *)controller {
}
#pragma mark - 在此代理处加载需要显示的文件
- (NSURL *)previewController:(QLPreviewController *)previewController previewItemAtIndex:(NSInteger)idx
{
return self.pdfUrl;
}
- (QLPreviewController *)qlpreView{
if (!_qlpreView) {
_qlpreView = [[QLPreviewController alloc]init];
_qlpreView.view.frame = CGRectMake(0, NavHeight, SCREEN_WIDTH, SCREEN_HEIGHT-NavHeight);
_qlpreView.delegate = self;
_qlpreView.dataSource = self;
}
return _qlpreView;
}
使用：
- (void)loadPDFMethod{
NSString *fileName = @"pdf20181204.pdf";
BOOL isExist = [kPDFToolMgr isExistPdfFileWithBase:self file:fileName];
if (!isExist) {
NSLog(@"Not Exist,LoadingFile");
//DownLoad
NSDictionary *data = @{@"file_name":fileName,
@"base64":self.base64String
};
[kPDFToolMgr writeFileWith:data completeBlock:^{
if (![kPDFToolMgr isExistPdfFileWithBase:self file:fileName]) {
NSLog(@"Load Error!");
} else{
NSLog(@"Load Success!");
}
}];
} else{
NSLog(@"Read Local File");
}
}
GitHub地址： https://github.com/liuyingjieyeah/YeahPDFTools
