ELCCameraOverlayView

ELCCameraOverlayView.h

//
//  ELCCameraOverlayView.h
//  ELC Technologies
//
//  Created by Marc Charbonneau on 8/19/11.
//  Copyright 2011 ELC Technologies. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface ELCCameraOverlayView : UIView <UIAccelerometerDelegate>
{
    UIButton *_button;
    UIInterfaceOrientation _interfaceOrientation;
}

@property(retain, nonatomic) UIButton *button;
@property(assign, nonatomic) UIInterfaceOrientation interfaceOrientation;

@end

ELCCameraOverlayView.m

//
//  ELCCameraOverlayView.m
//  ELC Technologies
//
//  Created by Marc Charbonneau on 8/19/11.
//  Copyright 2011 ELC Technologies. All rights reserved.
//

#import "ELCCameraOverlayView.h"

@implementation ELCCameraOverlayView

#pragma mark API

@synthesize button = _button;
@synthesize interfaceOrientation = _interfaceOrientation;

- (void)setButton:(UIButton *)button;
{
    if ( _button != button )
    {
        [_button removeFromSuperview];
        [_button release];
        _button = [button retain];
        [self addSubview:button];
    }
}

- (void)setInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation;
{
    if ( _interfaceOrientation != interfaceOrientation )
    {
        _interfaceOrientation = interfaceOrientation;
        [self setNeedsLayout];
    }
}

#pragma mark UIView

- (id)initWithFrame:(CGRect)frame;
{
    if ( ( self = [super initWithFrame:frame] ) )
    {
        _interfaceOrientation = UIInterfaceOrientationPortrait;
        _button = [[UIButton alloc] initWithFrame:CGRectMake( 240.0f, 0.0f, 80.0f, 80.0f )];
        
        [[UIAccelerometer sharedAccelerometer] setDelegate:self];
        [self addSubview:_button];
    }
    
    return self;
}

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event;
{
    if ( [super hitTest:point withEvent:event] == self.button )
        return self.button;
    
    return nil;
}

- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event;
{
    if ( CGRectContainsPoint( self.button.frame, point ) )
        return YES;
    
    return NO;
}

- (void)layoutSubviews;
{
    CGFloat width = CGRectGetWidth( self.button.frame );
    CGFloat height = CGRectGetHeight( self.button.frame );
    
    switch ( self.interfaceOrientation )
    {
        case UIInterfaceOrientationPortrait:
        case UIInterfaceOrientationPortraitUpsideDown:
            self.button.frame = CGRectMake( CGRectGetMaxX( self.bounds ) - width, 0.0f, width, height );
            break;
        case UIInterfaceOrientationLandscapeRight:
            self.button.frame = CGRectMake( CGRectGetMaxX( self.bounds ) - width, CGRectGetMaxY( self.bounds ) - height - 50.0f, width, height );
            break;
        case UIInterfaceOrientationLandscapeLeft:
            self.button.frame = CGRectMake( 0.0f, 0.0f, width, height );
            break;
    }
}

#pragma mark NSObject

- (void)dealloc;
{
    [[UIAccelerometer sharedAccelerometer] setDelegate:nil];
    [_button release];
    [super dealloc];
}

#pragma mark UIAccelerometerDelegate

- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration;
{ 
	CGFloat x = -[acceleration x]; 
	CGFloat y = [acceleration y]; 
	CGFloat angle = atan2(y, x); 
	
	if ( angle >= -2.25f && angle <= -0.25f )
	{
        self.interfaceOrientation = UIInterfaceOrientationPortrait;
	}
	else if ( angle >= -1.75f && angle <= 0.75f )
	{
        self.interfaceOrientation = UIInterfaceOrientationLandscapeRight;
	}
	else if ( angle >= 0.75f && angle <= 2.25f )
	{
        self.interfaceOrientation = UIInterfaceOrientationPortraitUpsideDown;
	}
	else if ( angle <= -2.25f || angle >= 2.25f )
	{
        self.interfaceOrientation = UIInterfaceOrientationLandscapeLeft;
	}
} 

@end