cacheFrame method
缓存frame
Implementation
Future<String> cacheFrame(FrameDetail frameDetail) async {
emit(
FrameSourceImageCaching(frameDetail),
);
FileInfo imgInfo =
await _imageCacheManager.downloadFile(frameDetail.image ?? '');
File img = imgInfo.file;
emit(
FrameSourceImageCached(
frameDetail,
img.path,
),
);
return img.path;
}