ofxWatcher

Notify when changes are made to a file or directory.

usage

ofxWatchPath(path, callback, [option], [retain]) ofxWatchPath(path, loader, callback, [option], [retain])

path

A path is specified as a relative or absolute path from the data folder. It can be a file or a directory or a path with wildcards. A wildcard is *(matches to any string) or **(matches to any directory recursively). If the path is for a directory, it watches all of the children.

(Example) If there are these files... 1. "videos/highQ/recorded.mov" 1. "videos/highQ/recorded.mp4" 1. "videos/lowQ/half.mov" 1. "videos/lowQ/sequence.mov" 1. "settings/playback/sequence.json"

• "videos//.mov" matches to 1,3,4
• "**/highQ" matches to 1,2
• "**/sequence*" matches to 4,5
• "**" matches to 1,2,3,4,5

callback

When changes are made to a file or directory while watching, the callback is called. Callback functions can take the following 4 forms. You can use function pointer or lambda as well.

1. callback(void) 1. callback(const std::filesystem::path&) 1. callback(const MediumType&) 1. callback(const MediumType&, const std::filesystem::path&)

MediumType is a product of loader function.

loader

Loader function modifies a path into any types. It is mainly intended to be used for loading the file.

(Example)

``C++ ofxWatchPath("settings/*.json", ofLoadJson, [](const ofJson &json) { std::cout << json.dump(2) << std::endl; });

Tips  
If you want to use an existing function that expects arguments other than filepath or a member function, consider using std::bind.

option

C++ ofxWatcherOption option; option.check_interval = 10; option.file_type_flag = ofx::watcher::REGULAR | ofx::watcher::DIRECTORY; option.absolute_path = true; option.finder_option.excludes = {".DS_Store",".git"}; option.finder_option.allow_ext = {".png",".jpg"}; `

float check_interval

Check for modifies at this interval in seconds. default: 1

std::size_t file_type_flag

Only checks files or directories of this type. See FileTypeFlag in ofxWatcher.h default: REGULAR

bool absolute_path

If true, callback or loader is called with absolute path. default: false

std::vector<std::string> excludes

Excludes files or directories that has a name in this vector. An exact match is required. default: [".DS_Store"]

std::vector<std::string> allow_ext

If specified, files with unspecified extensions are ignored. Each ext should start with .. default: (empty)

bool retain

If true, ofxWatcher keeps the shared_ptr created by ofxWatchPath. If you want to control the object's lifecycle, call ofxWatchPath with retain=false. default: true`