Patch 3

Classes/NVMapViewController.h

@@ -13,4 +13,6 @@
 	MKMapView *_mapView;
 }
 
+- (void)updatePolylineAnnotationView;
+
 @end

Classes/NVMapViewController.m

@@ -8,7 +8,7 @@
 
 #import "NVMapViewController.h"
 #import "NVPolylineAnnotationView.h"
-
+#import <QuartzCore/QuartzCore.h>
 
 @implementation NVMapViewController
 
@@ -98,7 +98,7 @@ - (void)loadView {
 					   nil];
 
 	NVPolylineAnnotation *annotation = [[[NVPolylineAnnotation alloc] initWithPoints:points mapView:_mapView] autorelease];
-	[_mapView addAnnotation:annotation];
+	[_mapView addAnnotation:annotation];	
 
 	// use some magic numbers to create a map region
 	MKCoordinateRegion region;
@@ -118,8 +118,54 @@ - (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnno
 	return nil;
 }
 
+// Find any polyline annotation and update its region.
+- (void)updatePolylineAnnotationView {
+	for (NSObject *a in [_mapView annotations]) {
+		if ([a isKindOfClass:[NVPolylineAnnotation class]]) {
+			NVPolylineAnnotation *polyline = (NVPolylineAnnotation *)a;
+
+			NSObject *pv = (NSObject *)[_mapView viewForAnnotation:polyline];
+			if ([pv isKindOfClass:[NVPolylineAnnotationView class]]) {
+				NVPolylineAnnotationView *polylineView = 
+					(NVPolylineAnnotationView *)[_mapView viewForAnnotation:polyline];
+
+				[polylineView regionChanged];
+			}
+		}		
+	}
+}
+
 - (void)dealloc {
     [super dealloc];
 }
 
+# pragma mark - MKMapViewDelegate
+
+- (void) mapView:(MKMapView *)mapView didAddAnnotationViews:(NSArray *)views {
+	// fixes that some marker are behind the polyline
+	for (int i=0; i<[views count]; i++) {
+		MKAnnotationView *view = [views objectAtIndex:i];
+		if ([view isKindOfClass:[NVPolylineAnnotationView class]]) {
+			[[view superview] sendSubviewToBack:view];
+
+			/* In iOS version above 4.0 we need to update the polyline view after it
+			 has been added to the mapview and it ready to be displayed. */
+			NSString *reqSysVer = @"4.0";
+			NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
+			if ([currSysVer compare:reqSysVer options:NSNumericSearch] != NSOrderedAscending) {
+				[self updatePolylineAnnotationView];
+			}
+		}
+	}
+}
+
+- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated {
+	/* In iOS version above 4.0 we need to update the polyline view after a region change */
+	NSString *reqSysVer = @"4.0";
+	NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
+	if ([currSysVer compare:reqSysVer options:NSNumericSearch] != NSOrderedAscending) {
+		[self updatePolylineAnnotationView];
+	}
+}
+
 @end

Classes/NVPolylineAnnotation.h

@@ -13,11 +13,10 @@
 @interface NVPolylineAnnotation : NSObject<MKAnnotation> {
 	NSMutableArray* _points; 
 	MKMapView* _mapView;
-
 }
 
--(id) initWithPoints:(NSArray*) points mapView:(MKMapView *)mapView;
-
 @property (nonatomic, retain) NSArray* points;
 
+-(id) initWithPoints:(NSArray*) points mapView:(MKMapView *)mapView;
+
 @end

Classes/NVPolylineAnnotation.m

@@ -11,12 +11,12 @@
 
 @implementation NVPolylineAnnotation
 
-@synthesize points = _points; 
+@synthesize points = _points;
 
 -(id) initWithPoints:(NSArray*) points mapView:(MKMapView *)mapView {
 	self = [super init];
 
-	_points = [[NSArray alloc] initWithArray:points];
+	_points = [points mutableCopy];
 	_mapView = [mapView retain];
 
 	return self;

Classes/NVPolylineAnnotationView.h

@@ -20,5 +20,6 @@
 
 - (id)initWithAnnotation:(NVPolylineAnnotation *)annotation
 				 mapView:(MKMapView *)mapView;
+- (void) regionChanged;
 
 @end

Classes/NVPolylineAnnotationView.m

@@ -5,8 +5,10 @@
 //  Created by William Lachance on 10-03-31.
 //  Inspired by code and ideas from Craig Spitzkoff and Nicolas Neubauer 2009.
 //
+//  Further development by Joerg Polakowski (www.mobile-melting.de)
 
 #import "NVPolylineAnnotationView.h"
+#import <QuartzCore/QuartzCore.h>
 
 const CGFloat POLYLINE_WIDTH = 4.0;
 
@@ -35,14 +37,19 @@ - (id) initWithPolylineView:(NVPolylineAnnotationView *)polylineView
 		self.clipsToBounds = NO;
 	}
 
+	// for debugging only to check when and how the polyline annotation view is updated
+	/*
+	CALayer *infoLayer = [self layer];
+	[infoLayer setBorderWidth:2];
+	[infoLayer setBorderColor:[[UIColor greenColor] CGColor]];
+	*/
 	return self;
 }
 
 -(void) drawRect:(CGRect)rect {
-
+	
 	NVPolylineAnnotation* annotation = (NVPolylineAnnotation*)_polylineView.annotation;
-	if (annotation.points && annotation.points.count > 0)
-	{
+	if (!self.hidden && annotation.points && annotation.points.count > 0) {
 		CGContextRef context = UIGraphicsGetCurrentContext(); 
 
 		CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
@@ -55,16 +62,92 @@ -(void) drawRect:(CGRect)rect {
 			CLLocation* location = [annotation.points objectAtIndex:i];
 			CGPoint point = [_mapView convertCoordinate:location.coordinate toPointToView:self];
 
-			if (i == 0)
-				CGContextMoveToPoint(context, point.x, point.y);
-			else
-				CGContextAddLineToPoint(context, point.x, point.y);
-		}
-
+			BOOL contains = CGRectContainsPoint(rect, point);
+			if (contains) {
+				CGPoint prevPoint = CGPointZero;
+				@try {
+					CLLocation *prevLocation = [annotation.points objectAtIndex:(i - 1)];
+					prevPoint = [_mapView convertCoordinate:prevLocation.coordinate 
+											  toPointToView:self];					
+					if (!CGRectContainsPoint(rect, prevPoint)) { // outside
+						CGContextMoveToPoint(context, prevPoint.x, prevPoint.y);
+					}
+				}
+				@catch(NSException *ex) { 
+					prevPoint = CGPointZero;
+				}
+
+				if (!CGPointEqualToPoint(prevPoint, CGPointZero)) { // prevPoint outside
+					CGContextAddLineToPoint(context, point.x, point.y);
+				}
+				else { // prevPoint inside
+					CGContextMoveToPoint(context, point.x, point.y);
+				}
+
+				CGPoint nextPoint = CGPointZero;
+				@try {
+					CLLocation *nextLocation = [annotation.points objectAtIndex:(i + 1)];
+					nextPoint = [_mapView convertCoordinate:nextLocation.coordinate 
+											  toPointToView:self];					
+					if (!CGRectContainsPoint(rect, nextPoint)) { // outside
+						CGContextAddLineToPoint(context, nextPoint.x, nextPoint.y);
+					}
+					else {
+						nextPoint = CGPointZero;
+					}
+				}
+				@catch(NSException *ex) { 
+					nextPoint = CGPointZero;
+				}
+			}
+			else {
+				// if current point is outside the drawing rect, check if the line drawn
+				// between current point and next point intersects with the drawing rect				
+				CGPoint nextPoint = CGPointZero;
+				@try {
+					CLLocation *nextLocation = [annotation.points objectAtIndex:(i + 1)];
+					nextPoint = [_mapView convertCoordinate:nextLocation.coordinate 
+											  toPointToView:self];					
+					if (!CGRectContainsPoint(rect, nextPoint)) { // outside, check intersection
+						CGMutablePathRef myPath = CGPathCreateMutable();
+						CGPathMoveToPoint(myPath, NULL, point.x, point.y );
+						CGPathAddLineToPoint(myPath, NULL, nextPoint.x, nextPoint.y);
+						CGPathCloseSubpath(myPath);
+
+						CGRect lineRect = CGPathGetBoundingBox(myPath);
+
+						if (CGRectIntersectsRect(rect, lineRect)) {
+							CGContextMoveToPoint(context, point.x, point.y);
+							CGContextAddLineToPoint(context, nextPoint.x, nextPoint.y);
+						}
+						CGPathRelease(myPath);
+					}
+				}
+				@catch(NSException *ex) { 
+					nextPoint = CGPointZero;
+				}				
+			}
+		}		
 		CGContextStrokePath(context);
 	}
 }
 
+- (BOOL) lineIntersectsRect:(CGRect)rect from:(CGPoint)a to:(CGPoint)b {
+	float lineSlope = (b.y - a.y) / (b.x - a.x);
+	float yIntercept = a.y - lineSlope * a.x;
+	float leftY = lineSlope * CGRectGetMinX(rect) + yIntercept;
+	float rightY = lineSlope * CGRectGetMaxX(rect) + yIntercept;
+
+	if (leftY >= CGRectGetMinY(rect) && leftY <= CGRectGetMaxY(rect)) {
+		return YES;
+	}
+	if (rightY >= CGRectGetMinY(rect) && rightY <= CGRectGetMaxY(rect)) {
+		return YES;
+	}
+	return NO;
+}
+
+
 -(void) dealloc {
 	[super dealloc];
 	[_mapView release];
@@ -86,7 +169,7 @@ - (id)initWithAnnotation:(NVPolylineAnnotation *)annotation
 		self.backgroundColor = [UIColor clearColor];
 		self.clipsToBounds = NO;
 		self.frame = CGRectMake(0.0, 0.0, _mapView.frame.size.width, _mapView.frame.size.height);
-
+		
 		_internalView = [[[NVPolylineInternalAnnotationView alloc] initWithPolylineView:self mapView:_mapView] autorelease];
 		[self addSubview:_internalView];
     }
@@ -96,31 +179,23 @@ - (id)initWithAnnotation:(NVPolylineAnnotation *)annotation
 -(void) regionChanged {
 	// move the internal route view. 
 
-	NVPolylineAnnotation* annotation = (NVPolylineAnnotation*)self.annotation;
-	CGPoint minpt, maxpt;
-	for (int i = 0; i < annotation.points.count; i++)
-	{
-		CLLocation* location = [annotation.points objectAtIndex:i];
-		CGPoint point = [_mapView convertCoordinate:location.coordinate toPointToView:_mapView];	
-		if (point.x < minpt.x || i == 0)
-			minpt.x = point.x;
-		if (point.y < minpt.y || i == 0)
-			minpt.y = point.y;
-		if (point.x > maxpt.x || i == 0)
-			maxpt.x = point.x;
-		if (point.y > maxpt.y || i == 0)
-			maxpt.y = point.y;
+	/* In iOS version 4.0 and above we need to calculate the new frame. Before iOS 4 setting
+	 the view's frame to the mapview's frame was sufficient*/
+	NSString *reqSysVer = @"4.0";
+	NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
+	if ([currSysVer compare:reqSysVer options:NSNumericSearch] != NSOrderedAscending) {
+		CGPoint origin = CGPointMake(0, 0);
+		origin = [_mapView convertPoint:origin toView:self];	
+		_internalView.frame = CGRectMake(origin.x, origin.y, _mapView.frame.size.width, _mapView.frame.size.height);
+	}
+	else { // iOS < 4.0
+		_internalView.frame = _mapView.frame;
 	}
 
-	CGFloat w = maxpt.x - minpt.x + (2*POLYLINE_WIDTH);
-	CGFloat h = maxpt.y - minpt.y + (2*POLYLINE_WIDTH);
-
-	_internalView.frame = CGRectMake(minpt.x - POLYLINE_WIDTH, minpt.y - POLYLINE_WIDTH, 
-									 w, h);
 	[_internalView setNeedsDisplay];
 }
 
-- (CGPoint) centerOffset {
+- (CGPoint) centerOffset {	
 	// HACK: use the method to get the centerOffset (called by the main mapview)
 	// to reposition our annotation subview in response to zoom and motion 
 	// events

README

@@ -3,6 +3,11 @@ MKMapView that continues to display correctly even as a user pinches and zooms
 the map. It incorporates and expands upon ideas from Craig Spitzkoff and
 Nicolas Neubauer.
 
+This solution is focused on iPhone OS versions pro to 4.x
+Note: In iPhone OS 4.0 the MKPolyline has been added.
+
+However, if you want to create an application, which should run on iOS versions prior to 4.x and make use of a polyline, you should use this project's polyline implementation.
+
 For more information, see:
 
 http://navarra.ca/?p=786
@@ -11,3 +16,9 @@ For information on the inspiration behind this original work, see:
 
 http://spitzkoff.com/craig/?p=65
 http://pixelfehler.nicolas-neubauer.de/2009/09/04/mapkit-google-maps-iphone-and-drawing-routes-or-polylines/
+
+The original example from http://github.com/wlach contained some bugs, which did not seem to get fixed. Bugs fixed:
+- Polyline View overlaps other Annotation Views (http://github.com/wlach/nvpolyline/issues#issue/2)
+- App crashes when zoomed in (http://github.com/wlach/nvpolyline/issues#issue/1)
+
+

nvpolyline.xcodeproj/project.pbxproj

@@ -16,6 +16,7 @@
 		1D60589B0D05DD56006BFB54 /* main.m in Sources */ = {isa = PBXBuildFile; fileRef = 29B97316FDCFA39411CA2CEA /* main.m */; };
 		1D60589F0D05DD5A006BFB54 /* Foundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1D30AB110D05D00D00671497 /* Foundation.framework */; };
 		1DF5F4E00D08C38300B7A737 /* UIKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1DF5F4DF0D08C38300B7A737 /* UIKit.framework */; };
+		1FF5265011FEC1540018A36F /* QuartzCore.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1FF5264F11FEC1540018A36F /* QuartzCore.framework */; };
 		288765FD0DF74451002DB57D /* CoreGraphics.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 288765FC0DF74451002DB57D /* CoreGraphics.framework */; };
 		28AD733F0D9D9553002E5188 /* MainWindow.xib in Resources */ = {isa = PBXBuildFile; fileRef = 28AD733E0D9D9553002E5188 /* MainWindow.xib */; };
 /* End PBXBuildFile section */
@@ -34,6 +35,7 @@
 		1D3623250D0F684500981E51 /* nvpolylineAppDelegate.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = nvpolylineAppDelegate.m; sourceTree = "<group>"; };
 		1D6058910D05DD3D006BFB54 /* nvpolyline.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = nvpolyline.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		1DF5F4DF0D08C38300B7A737 /* UIKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = UIKit.framework; path = System/Library/Frameworks/UIKit.framework; sourceTree = SDKROOT; };
+		1FF5264F11FEC1540018A36F /* QuartzCore.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = QuartzCore.framework; path = iphoneos3.1.3/System/Library/Frameworks/QuartzCore.framework; sourceTree = "<group>"; };
 		288765FC0DF74451002DB57D /* CoreGraphics.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreGraphics.framework; path = System/Library/Frameworks/CoreGraphics.framework; sourceTree = SDKROOT; };
 		28AD733E0D9D9553002E5188 /* MainWindow.xib */ = {isa = PBXFileReference; lastKnownFileType = file.xib; path = MainWindow.xib; sourceTree = "<group>"; };
 		29B97316FDCFA39411CA2CEA /* main.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = main.m; sourceTree = "<group>"; };
@@ -51,6 +53,7 @@
 				288765FD0DF74451002DB57D /* CoreGraphics.framework in Frameworks */,
 				069D56261162FB1B009B3FF2 /* MapKit.framework in Frameworks */,
 				069D57F81164E2A3009B3FF2 /* CoreLocation.framework in Frameworks */,
+				1FF5265011FEC1540018A36F /* QuartzCore.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -113,6 +116,7 @@
 		29B97323FDCFA39411CA2CEA /* Frameworks */ = {
 			isa = PBXGroup;
 			children = (
+				1FF5264F11FEC1540018A36F /* QuartzCore.framework */,
 				1DF5F4DF0D08C38300B7A737 /* UIKit.framework */,
 				1D30AB110D05D00D00671497 /* Foundation.framework */,
 				288765FC0DF74451002DB57D /* CoreGraphics.framework */,
@@ -190,13 +194,16 @@
 			isa = XCBuildConfiguration;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
+				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "Don't Code Sign";
 				COPY_PHASE_STRIP = NO;
 				GCC_DYNAMIC_NO_PIC = NO;
 				GCC_OPTIMIZATION_LEVEL = 0;
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
 				GCC_PREFIX_HEADER = nvpolyline_Prefix.pch;
 				INFOPLIST_FILE = "nvpolyline-Info.plist";
 				PRODUCT_NAME = nvpolyline;
+				"PROVISIONING_PROFILE[sdk=iphoneos*]" = "";
+				SDKROOT = iphoneos4.0;
 			};
 			name = Debug;
 		};