Add QR code encoder implementation for IOS

plugin.xml

@@ -39,6 +39,8 @@
         <framework src="AssetsLibrary.framework" />
         <framework src="CoreVideo.framework" />
         <framework src="QuartzCore.framework" />
+        <framework src="CoreGraphics.framework" />
+        <framework src="CoreImage.framework" />
     </platform>
 
     <!-- android -->

src/ios/CDVBarcodeScanner.mm

@@ -15,13 +15,11 @@
 // use the all-in-one version of zxing that we built
 //------------------------------------------------------------------------------
 #import "zxing-all-in-one.h"
-
 #import <Cordova/CDVPlugin.h>
 
 
 //------------------------------------------------------------------------------
 // Delegate to handle orientation functions
-// 
 //------------------------------------------------------------------------------
 @protocol CDVBarcodeScannerOrientationDelegate <NSObject>
 
@@ -48,6 +46,7 @@ @interface CDVBarcodeScanner : CDVPlugin {}
 - (NSString*)isScanNotPossible;
 - (void)scan:(CDVInvokedUrlCommand*)command;
 - (void)encode:(CDVInvokedUrlCommand*)command;
+- (void)returnImage:(NSString*)filePath callback:(NSString*)callback;
 - (void)returnSuccess:(NSString*)scannedText format:(NSString*)format cancelled:(BOOL)cancelled flipped:(BOOL)flipped callback:(NSString*)callback;
 - (void)returnError:(NSString*)message callback:(NSString*)callback;
 @end
@@ -85,6 +84,19 @@ - (UIImage*) getImageFromLuminanceSource:(zxing::LuminanceSource*)luminanceSourc
 - (void)dumpImage:(UIImage*)image;
 @end
 
+//------------------------------------------------------------------------------
+// Qr encoder processor
+//------------------------------------------------------------------------------
+@interface CDVqrProcessor: NSObject
+@property (nonatomic, retain) CDVBarcodeScanner*          plugin;
+@property (nonatomic, retain) NSString*                   callback;
+@property (nonatomic, retain) NSString*                   stringToEncode;
+@property                     NSInteger                   size;
+
+- (id)initWithPlugin:(CDVBarcodeScanner*)plugin callback:(NSString*)callback stringToEncode:(NSString*)stringToEncode;
+- (void)generateImage;
+@end
+
 //------------------------------------------------------------------------------
 // view controller for the ui
 //------------------------------------------------------------------------------
@@ -130,7 +142,7 @@ - (void)scan:(CDVInvokedUrlCommand*)command {
 
     callback = command.callbackId;
 
-    // We allow the user to define an alternate xib file for loading the overlay. 
+    // We allow the user to define an alternate xib file for loading the overlay.
     NSString *overlayXib = nil;
     if ( [command.arguments count] >= 1 )
     {
@@ -158,7 +170,33 @@ - (void)scan:(CDVInvokedUrlCommand*)command {
 
 //--------------------------------------------------------------------------
 - (void)encode:(CDVInvokedUrlCommand*)command {
-    [self returnError:@"encode function not supported" callback:command.callbackId];
+    if([command.arguments count] < 1)
+        [self returnError:@"Too few arguments!" callback:command.callbackId];
+
+    CDVqrProcessor* processor;
+    NSString*       callback;
+    callback = command.callbackId;
+
+    processor = [[CDVqrProcessor alloc]
+                 initWithPlugin:self
+                 callback:callback
+                 stringToEncode: command.arguments[0][@"data"]
+                 ];
+
+    [processor retain];
+    [processor retain];
+    [processor retain];
+    // queue [processor generateImage] to run on the event loop
+    [processor performSelector:@selector(generateImage) withObject:nil afterDelay:0];
+}
+
+- (void)returnImage:(NSString*)filePath callback:(NSString*)callback{
+    CDVPluginResult* result = [CDVPluginResult
+                               resultWithStatus: CDVCommandStatus_OK
+                               messageAsString:filePath
+                               ];
+
+    [[self commandDelegate] sendPluginResult:result callbackId:callback];
 }
 
 //--------------------------------------------------------------------------
@@ -315,9 +353,9 @@ - (NSString*)setUpCaptureSession {
     AVCaptureSession* captureSession = [[AVCaptureSession alloc] init];
     self.captureSession = captureSession;
 
-       AVCaptureDevice* __block device = nil;
+    AVCaptureDevice* __block device = nil;
     if (self.isFrontCamera) {
-
+        
         NSArray* devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
         [devices enumerateObjectsUsingBlock:^(AVCaptureDevice *obj, NSUInteger idx, BOOL *stop) {
             if (obj.position == AVCaptureDevicePositionFront) {
@@ -329,7 +367,7 @@ - (NSString*)setUpCaptureSession {
         if (!device) return @"unable to obtain video capture device";
 
     }
-
+    
 
     AVCaptureDeviceInput* input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
     if (!input) return @"unable to obtain video capture device input";
@@ -622,6 +660,84 @@ - (void)dumpImage:(UIImage*)image {
 
 @end
 
+//------------------------------------------------------------------------------
+// qr encoder processor
+//------------------------------------------------------------------------------
+@implementation CDVqrProcessor
+@synthesize plugin               = _plugin;
+@synthesize callback             = _callback;
+@synthesize stringToEncode       = _stringToEncode;
+@synthesize size                 = _size;
+
+- (id)initWithPlugin:(CDVBarcodeScanner*)plugin callback:(NSString*)callback stringToEncode:(NSString*)stringToEncode{
+    self = [super init];
+    if (!self) return self;
+
+    self.plugin          = plugin;
+    self.callback        = callback;
+    self.stringToEncode  = stringToEncode;
+    self.size            = 300;
+
+    return self;
+}
+
+//--------------------------------------------------------------------------
+- (void)dealloc {
+    self.plugin = nil;
+    self.callback = nil;
+    self.stringToEncode = nil;
+
+    [super dealloc];
+}
+//--------------------------------------------------------------------------
+- (void)generateImage{
+    /* setup qr filter */
+    CIFilter *filter = [CIFilter filterWithName:@"CIQRCodeGenerator"];
+    [filter setDefaults];
+
+    /* set filter's input message
+     * the encoding string has to be convert to a UTF-8 encoded NSData object */
+    [filter setValue:[self.stringToEncode dataUsingEncoding:NSUTF8StringEncoding]
+              forKey:@"inputMessage"];
+
+    /* on ios >= 7.0  set low image error correction level */
+    if (floor(NSFoundationVersionNumber) >= NSFoundationVersionNumber_iOS_7_0)
+        [filter setValue:@"L" forKey:@"inputCorrectionLevel"];
+
+    /* prepare cgImage */
+    CIImage *outputImage = [filter outputImage];
+    CIContext *context = [CIContext contextWithOptions:nil];
+    CGImageRef cgImage = [context createCGImage:outputImage
+                                       fromRect:[outputImage extent]];
+
+    /* returned qr code image */
+    UIImage *qrImage = [UIImage imageWithCGImage:cgImage
+                                           scale:1.
+                                     orientation:UIImageOrientationUp];
+    /* resize generated image */
+    CGFloat width = _size;
+    CGFloat height = _size;
+
+    UIGraphicsBeginImageContext(CGSizeMake(width, height));
+
+    CGContextRef ctx = UIGraphicsGetCurrentContext();
+    CGContextSetInterpolationQuality(ctx, kCGInterpolationNone);
+    [qrImage drawInRect:CGRectMake(0, 0, width, height)];
+    qrImage = UIGraphicsGetImageFromCurrentImageContext();
+
+    /* clean up */
+    UIGraphicsEndImageContext();
+    CGImageRelease(cgImage);
+
+    /* save image to file */
+    NSString* filePath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"tmpqrcode.jpeg"];
+    [UIImageJPEGRepresentation(qrImage, 1.0) writeToFile:filePath atomically:YES];
+
+    /* return file path back to cordova */
+    [self.plugin returnImage:filePath callback: self.callback];
+}
+@end
+
 //------------------------------------------------------------------------------
 // view controller for the ui
 //------------------------------------------------------------------------------
@@ -649,7 +765,7 @@ - (void)dealloc {
 //    self.processor = nil;
     self.shutterPressed = NO;
     self.alternateXib = nil;
-    self.overlayView = nil;      
+    self.overlayView = nil;
     [super dealloc];
 }
 
@@ -710,7 +826,7 @@ - (void)flipCameraButtonPressed:(id)sender
 }
 
 //--------------------------------------------------------------------------
-- (UIView *)buildOverlayViewFromXib 
+- (UIView *)buildOverlayViewFromXib
 {
     [[NSBundle mainBundle] loadNibNamed:self.alternateXib owner:self options:NULL];
 
@@ -720,7 +836,7 @@ - (UIView *)buildOverlayViewFromXib
         return nil;
     }
 
-    return self.overlayView;        
+    return self.overlayView;
 }
 
 //--------------------------------------------------------------------------
@@ -759,7 +875,6 @@ - (UIView*)buildOverlayView {
                        target:(id)self
                        action:@selector(flipCameraButtonPressed:)
                        ];
-
 
 #if USE_SHUTTER
     id shutterButton = [[UIBarButtonItem alloc]
@@ -858,7 +973,7 @@ - (UIImage*)buildReticleImage {
 #pragma mark CDVBarcodeScannerOrientationDelegate
 
 - (BOOL)shouldAutorotate
-{   
+{
     return NO;
 }