crash at drawInRect:rect, I've the solution but don't know how?
The app works fine with the iphone 开发者_开发问答simulator but when we run it in the actual iphone device it crashes at the following line:
[ucdView.image drawInRect:rect];
I've searched and found the solution but I don't know how to solve as the time is very short when we have to present it on this Friday. Look at the following solution: Must drawInRect: for a separate context be executed on the main thread?
The part where this crash happen is in Sculpture.m inside viewDidLoad()
- (void)viewDidLoad{
[super viewDidLoad];
CLController = [[CoreLocationController alloc] init];
CLController.delegate = self;
[CLController.locMgr startUpdatingLocation];
currentLoc = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"redPin.png"]];
UIImage *ucdImage = [UIImage imageNamed:@"ucd.png"];
self.ucdView = [[UIImageView alloc] initWithImage:ucdImage];//creating a view for UCD image
ucdView.userInteractionEnabled = YES;
[self loadingFile];
UIScrollView *myScrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
[myScrollView setMinimumZoomScale:0.35];
[myScrollView setMaximumZoomScale:2.0];
myScrollView.clipsToBounds = YES;
myScrollView.bounces = YES;
myScrollView.contentOffset = CGPointMake(1400, 700);
[myScrollView setContentSize:CGSizeMake(ucdImage.size.width, ucdImage.size.height)];
[myScrollView setDelegate:self];
[myScrollView addSubview:ucdView];//adding ucd view to scroll view
[self.view addSubview:myScrollView]; // adding scrollview to self.view main view
[myScrollView release];
//Drawing The Line
UIGraphicsBeginImageContext(ucdView.frame.size);
CGRect rect = CGRectMake(0, 0, ucdView.frame.size.width, ucdView.frame.size.height);
[ucdView.image drawInRect:rect];
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(context, 3.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGFloat dashArray[] = {2,0,2,2};
CGContextSetLineDash(context, 3, dashArray, 5);
CGContextMoveToPoint(context,[self longt_to_x:[[path_array objectAtIndex:0] doubleValue]],[self lat_to_y:[[path_array objectAtIndex:1] doubleValue]]);
int path_length = [path_array count];
for(int i = 2; i<path_length; i = i+2){
CGContextAddLineToPoint(context,[self longt_to_x:[[path_array objectAtIndex:i] doubleValue]],[self lat_to_y:[[path_array objectAtIndex:i+1] doubleValue]]);
}
CGContextStrokePath(context);
ucdView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
Thanks a million in advance...
You didn't say where exactly the crash was, but you have already created one image context with UIGraphicsBeginImageContext
, and then you create another one with CGBitmapContextCreate
. My guess is that the later one is the problem (getting the arguments right can be tricky) and isn't what you want anyway. So change it to:
// Get the current drawing context which is the image context right now
CGContextRef context = UIGraphicsGetCurrentContext();
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