zxing/iphone/ZXingWidget/Classes/OverlayView.m

/**
 * Copyright 2009 Jeff Verkoeyen
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import "OverlayView.h"

static const CGFloat kPadding = 10;

@implementation OverlayView

@synthesize delegate, oneDMode;
@synthesize points = _points;
//@synthesize image;


////////////////////////////////////////////////////////////////////////////////////////////////////
- (id)initWithCancelEnabled:(BOOL)cancelEnabled frame:(CGRect)frame {
	if( self = [super initWithFrame:frame] ) {
		self.backgroundColor = [UIColor clearColor];
	}
	if (cancelEnabled) {
		cancelButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
		[cancelButton setTitle:@"Cancel" forState:UIControlStateNormal];
		if (oneDMode) {
			[cancelButton setTransform:CGAffineTransformMakeRotation(M_PI/2)];
			[cancelButton setFrame:CGRectMake(20, 175, 45, 130)];
		}
		else {
			[cancelButton setFrame:CGRectMake(95, 420, 130, 45)];			
		}

		[cancelButton addTarget:self action:@selector(cancel:) forControlEvents:UIControlEventTouchUpInside];
		[self addSubview:cancelButton];
	}
	return self;
}

- (void)cancel:(id)sender {
	// call delegate to cancel this scanner
	if (delegate != nil) {
		[delegate cancelled];
	}
}

////////////////////////////////////////////////////////////////////////////////////////////////////
- (void) dealloc {
	[imageView release];
	imageView = nil;
	[_points release];
	_points = nil;
	[cancelButton release];
	[super dealloc];
}


- (void)drawRect:(CGRect)rect inContext:(CGContextRef)context {
	CGContextBeginPath(context);
	CGContextMoveToPoint(context, rect.origin.x, rect.origin.y);
	CGContextAddLineToPoint(context, rect.origin.x + rect.size.width, rect.origin.y);
	CGContextAddLineToPoint(context, rect.origin.x + rect.size.width, rect.origin.y + rect.size.height);
	CGContextAddLineToPoint(context, rect.origin.x, rect.origin.y + rect.size.height);
	CGContextAddLineToPoint(context, rect.origin.x, rect.origin.y);
	CGContextStrokePath(context);
}


////////////////////////////////////////////////////////////////////////////////////////////////////
- (void)drawRect:(CGRect)rect {
	[super drawRect:rect];
	CGContextRef c = UIGraphicsGetCurrentContext();

	CGRect cropRect = [self cropRect];
	
	if (nil != _points) {
//		[imageView.image drawAtPoint:cropRect.origin];
	}
	
	CGFloat white[4] = {1.0f, 1.0f, 1.0f, 1.0f};
	CGContextSetStrokeColor(c, white);
	CGContextSetFillColor(c, white);
	[self drawRect:cropRect inContext:c];
	
//	CGContextSetStrokeColor(c, white);
	//	CGContextSetStrokeColor(c, white);
	CGContextSaveGState(c);
	if (oneDMode) {
		char *text = "Place a red line over the bar code to be scanned.";
		CGContextSelectFont(c, "Helvetica", 15, kCGEncodingMacRoman);
		CGContextScaleCTM(c, -1.0, 1.0);
		CGContextRotateCTM(c, M_PI/2);
		CGContextShowTextAtPoint(c, 74.0, 285.0, text, 49);
	}
	else {
		char *text = "Place a barcode inside the";
		char *text2 = "viewfinder rectangle to scan it.";
		CGContextSelectFont(c, "Helvetica", 18, kCGEncodingMacRoman);
		CGContextScaleCTM(c, -1.0, 1.0);
		CGContextRotateCTM(c, M_PI);
		CGContextShowTextAtPoint(c, 48.0, -45.0, text, 26);
		CGContextShowTextAtPoint(c, 33.0, -70.0, text2, 32);
	}
	CGContextRestoreGState(c);
	int offset = rect.size.width / 2;
	if (oneDMode) {
		CGFloat red[4] = {1.0f, 0.0f, 0.0f, 1.0f};
		CGContextSetStrokeColor(c, red);
		CGContextSetFillColor(c, red);
		CGContextBeginPath(c);
		//		CGContextMoveToPoint(c, rect.origin.x + kPadding, rect.origin.y + offset);
		//		CGContextAddLineToPoint(c, rect.origin.x + rect.size.width - kPadding, rect.origin.y + offset);
		CGContextMoveToPoint(c, rect.origin.x + offset, rect.origin.y + kPadding);
		CGContextAddLineToPoint(c, rect.origin.x + offset, rect.origin.y + rect.size.height - kPadding);
		CGContextStrokePath(c);
	}
	if( nil != _points ) {
		CGFloat blue[4] = {0.0f, 1.0f, 0.0f, 1.0f};
		CGContextSetStrokeColor(c, blue);
		CGContextSetFillColor(c, blue);
		if (oneDMode) {
			CGPoint val1 = [[_points objectAtIndex:0] CGPointValue];
			CGPoint val2 = [[_points objectAtIndex:1] CGPointValue];
			CGContextMoveToPoint(c, offset, val1.x);
			CGContextAddLineToPoint(c, offset, val2.x);
			CGContextStrokePath(c);
		}
		else {
			CGRect smallSquare = CGRectMake(0, 0, 10, 10);
			for( NSValue* value in _points ) {
				CGPoint point = [value CGPointValue];
				smallSquare.origin = CGPointMake(
								cropRect.origin.x + point.x - smallSquare.size.width / 2,
								cropRect.origin.y + point.y - smallSquare.size.height / 2);
				[self drawRect:smallSquare inContext:c];
			}
		}
	}
}


////////////////////////////////////////////////////////////////////////////////////////////////////
/*
- (void) setImage:(UIImage*)image {
	if( nil == _imageView ) {
		_imageView = [[UIImageView alloc] initWithImage:image];
		_imageView.alpha = 0.5;
	} else {
		_imageView.image = image;
	}
	
	CGRect frame = _imageView.frame;
	frame.origin.x = self.cropRect.origin.x;
	frame.origin.y = self.cropRect.origin.y;
	_imageView.frame = frame;
	
	[_points release];
	_points = nil;
	self.backgroundColor = [UIColor clearColor];
	
	[self setNeedsDisplay];
}
*/

////////////////////////////////////////////////////////////////////////////////////////////////////
- (UIImage*) image {
	return imageView.image;
}


////////////////////////////////////////////////////////////////////////////////////////////////////
- (CGRect) cropRect {
	CGFloat rectSize = self.frame.size.width - kPadding * 2;
	if (!oneDMode) {
		return CGRectMake(kPadding, (self.frame.size.height - rectSize) / 2, rectSize, rectSize);
	}
	else {
		CGFloat rectSize2 = self.frame.size.height - kPadding * 2;
		return CGRectMake(kPadding, kPadding, rectSize, rectSize2);		
	}
}


////////////////////////////////////////////////////////////////////////////////////////////////////
- (void) setPoints:(NSArray*)pnts {
	[pnts retain];
	[_points release];
	_points = pnts;
	
	if (pnts != nil) {
		self.backgroundColor = [UIColor colorWithWhite:1.0 alpha:0.25];
	}
	[self setNeedsDisplay];
}


@end