iOS QR code scan

Every step: Add Avfoundation.framework Library

General > Linked Frameworks and Libraries

Step Two: Code integration

#import "ViewController.h"

#import <AVFoundation/AVFoundation.h>

1. There's a material.

@interface Viewcontroller () <AVCaptureMetadataOutputObjectsDelegate>

/** 2. Input settings capture the information captured by the camera */

@property (nonatomic, strong) Avcapturedeviceinput *input;

/** 3. Output device parsing the information collected by the input device */

@property (nonatomic, strong) Avcapturemetadataoutput *output;

/** 4. Layer (the special layer can show the image captured by the camera) shows the information collected by the input device * *

@property (nonatomic, strong) Avcapturevideopreviewlayer *layer;

/** 5. Associating input devices and output device sessions */

@property (nonatomic, strong) avcapturesession *session;

@end

@implementation Viewcontroller

-(void) Viewdidload {

[Super Viewdidload];

}

Click Scan QR Code

-(Ibaction) Click: (ID) Sender {

1. Create an input device

Avmediatypevideo camera

Avmediatypeaudio microphone

Avcapturedeviceinput input Device Default back

Avcapturedevice *device = [Avcapturedevice defaultdevicewithmediatype:avmediatypevideo];

Nsarray *alldevice = [Avcapturedevice deviceswithmediatype:avmediatypevideo];

Self.input = [Avcapturedeviceinput deviceinputwithdevice:[alldevice firstobject] error:nil];

2. Creating an output device

Self.output = [[Avcapturemetadataoutput alloc]init];

Parse the returned data

Set the proxy for the output device to return the parsed data

[Self.output setmetadataobjectsdelegate:self Queue:dispatch_get_main_queue ()];

3. Create a session

Self.session = [[Avcapturesession alloc]init];

4. Associating sessions and devices

if ([Self.session canAddInput:self.input]) {

[Self.session AddInput:self.input];

}

if ([Self.session canAddOutput:self.output]) {

[Self.session AddOutput:self.output];

}

Tell the data type Avmetadataobjecttypeqrcode two-dimensional code

Self.output.metadataObjectTypes = @[avmetadataobjecttypeqrcode];

Scan box Size entire screen

[Self.session setsessionpreset:avcapturesessionpreset640x480];

5. Assign a frame to the layer and add it to the view

Self.layer = [[Avcapturevideopreviewlayer alloc]initwithsession:self.session];

Self.layer.frame = Self.view.bounds;

[Self.view.layer AddSublayer:self.layer];

Open session

[Self.session startrunning];

}

The method that will be called when the result is scanned

-(void) Captureoutput: (Avcaptureoutput *) captureoutput didoutputmetadataobjects: (Nsarray *) metadataobjects Fromconnection: (avcaptureconnection *) connection{

Avmetadatamachinereadablecodeobject *OBJC = [Metadataobjects firstobject];

NSString *str = Objc.stringvalue;

NSLog (@ "%@", str);

Stop scanning

[Self.session stoprunning];

Remove Layer

[Self.layer Removefromsuperlayer];

}

@end

iOS QR code scan