iOS 掃描相簿圖片二維碼
阿新 • • 發佈:2018-12-13
級別:★★☆☆☆
標籤:「iOS CIDetector」「CIQRCodeFeature」「識別相簿圖片」
作者: Xs·H
審校: QiShare團隊
接上篇 iOS 掃描二維碼/條形碼,本文補充介紹掃描相簿圖片上二維碼的實現方式。先看看QiQRCode中的示例效果:
iOS 8
之後,可以結合CIDetector
使用CIQRCodeFeature
實現掃描相簿圖片上二維碼的功能。具體實現過程如下:
1、遵守協議
@interface QiCodeManager () <UIImagePickerControllerDelegate, UINavigationControllerDelegate>
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2、開啟相簿
- (void)presentPhotoLibraryWithRooter:(UIViewController *)rooter callback:(nonnull void (^)(NSString * _Nonnull))callback {
_callback = callback;
UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
// imagePicker.allowsEditing = YES;
imagePicker.delegate = self;
[rooter presentViewController:imagePicker animated:YES completion:nil];
}
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3、實現代理
// UIImagePickerControllerDelegate
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<UIImagePickerControllerInfoKey,id> *)info {
UIImage *pickedImage = info[UIImagePickerControllerEditedImage] ?: info[UIImagePickerControllerOriginalImage];
CIImage *detectImage = [CIImage imageWithData:UIImagePNGRepresentation(pickedImage)];
CIDetector *detector = [CIDetector detectorOfType:CIDetectorTypeQRCode context:nil options:@{CIDetectorAccuracy: CIDetectorAccuracyLow}];
CIQRCodeFeature *feature = (CIQRCodeFeature *)[detector featuresInImage:detectImage options:nil].firstObject;
[picker dismissViewControllerAnimated:YES completion:^{
if (feature.messageString) {
[self handleCodeString:feature.messageString];
}
}];
}
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4、透傳給業務
- (void)handleCodeString:(NSString *)codeString {
if (_autoStop) {
[self stopScanning];
}
if (_callback) {
_callback(codeString);
}
}
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5、業務呼叫方式
// 建立“相簿”按鈕
UIBarButtonItem *photoItem = [[UIBarButtonItem alloc] initWithTitle:@"相簿" style:UIBarButtonItemStylePlain target:self action:@selector(photo:)];
self.navigationItem.rightBarButtonItem = photoItem;
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// 實現“相簿”按鈕方法
- (void)photo:(id)sender {
__weak typeof(self) weakSelf = self;
[_codeManager presentPhotoLibraryWithRooter:self callback:^(NSString * _Nonnull code) {
[weakSelf performSegueWithIdentifier:@"showCodeGeneration" sender:code];
}];
}
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上述程式碼中的核心步驟是第3步—實現代理。 我們通過
UIImagePickerController
拿到image
後,使用CIDetector
和CIQRCodeFeature
讀取image
上的資訊,最終得到的feature.messageString
就是二維碼的字串資訊。
示例原始碼QiQRCode可從GitHub的QiShare開源庫中獲取。
關注我們的途徑有:
QiShare(簡書)
QiShare(掘金)
QiShare(知乎)
QiShare(GitHub)
QiShare(CocoaChina)
QiShare(StackOverflow)
QiShare(微信公眾號)
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