抱歉，如果这个问题太模糊，但是我真的不明白发生了什么。
我有一个集成了crashlytics lib的应用程序。而且我有一些奇怪的崩溃。这是日志:
102行是
[path addArcWithCenter:CGPointMake(kLeftHorizontalMargin + xScale*i/2, kVerticalTopMargin + (maxValue - value)*yScale) radius:kPathLineWidth startAngle:0 endAngle:2*M_PI clockwise:YES];
还有一点:
线程:崩溃:com.apple.main-thread
0 libsystem_kernel.dylib 0x3846f1fc __pthread_kill + 8
1 libsystem_pthread.dylib 0x384d6a53 pthread_kill + 58
2 libsystem_c.dylib 0x3842002d abort + 76
3 libsystem_c.dylib 0x383ffc6b __assert_rtn + 182
4 CoreGraphics 0x2dc60563 CGPathAddArc + 186
5 UIKit 0x30589ed7 -[UIBezierPath addArcWithCenter:radius:startAngle:endAngle:clockwise:] + 70
6 Exchange 0x00010d25 -[GraphView drawRect:] (GraphView.m:102)
7 UIKit 0x303cb749 -[UIView(CALayerDelegate) drawLayer:inContext:] + 372
8 QuartzCore 0x30002049 -[CALayer drawInContext:] + 100
9 QuartzCore 0x2ffeb813 CABackingStoreUpdate_ + 1858
10 QuartzCore 0x300c5735 ___ZN2CA5Layer8display_Ev_block_invoke + 52
11 QuartzCore 0x2ffeb0c3 x_blame_allocations + 82
12 QuartzCore 0x2ffead77 CA::Layer::display_() + 1118
13 QuartzCore 0x2ffce969 CA::Layer::display_if_needed(CA::Transaction*) + 208
14 QuartzCore 0x2ffce601 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 24
15 QuartzCore 0x2ffce00d CA::Context::commit_transaction(CA::Transaction*) + 228
16 QuartzCore 0x2ffcde1f CA::Transaction::commit() + 314
17 QuartzCore 0x2ffc7b4d CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) + 56
18 CoreFoundation 0x2db90f71 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 20
19 CoreFoundation 0x2db8e8ff __CFRunLoopDoObservers + 286
20 CoreFoundation 0x2db8ec4b __CFRunLoopRun + 738
21 CoreFoundation 0x2daf9541 CFRunLoopRunSpecific + 524
22 CoreFoundation 0x2daf9323 CFRunLoopRunInMode + 106
23 GraphicsServices 0x328302eb GSEventRunModal + 138
24 UIKit 0x303b01e5 UIApplicationMain + 1136
25 Exchange 0x00022507 main (main.m:16)
这是我的
drawRect::- (void)drawRect:(CGRect)rect
{
[super drawRect:rect];
if (self.datesAndValues.count == 0)
return;
double xScale = (self.frame.size.width - kLeftHorizontalMargin - kRightHorizontalMargin)/((self.datesAndValues.count - 1)/2);
double yScale;
if (maxValue == minValue)
yScale = 1;
else
yScale = (self.frame.size.height - kVerticalTopMargin - kVerticalBottomMargin)/(maxValue - minValue);
[self drawWeekSeparatorsInRect:rect
withXScale:xScale];
UIFont* bigFont = [UIFont fontWithName:@"HelveticaNeue-Light" size:kMinMaxLabelFontSize];
UIFont* smallFont = [UIFont fontWithName:@"HelveticaNeue-Light" size:kLocalMinMaxLabelFontSize];
UIBezierPath* path = [UIBezierPath bezierPath];
for (NSInteger i=0; i<self.datesAndValues.count; i+=2)
{
double value = [self.datesAndValues[i+1] doubleValue];
if (i == 0)
[path moveToPoint:CGPointMake(kLeftHorizontalMargin, kVerticalTopMargin + (maxValue - value)*yScale)];
else
[path addLineToPoint:CGPointMake(kLeftHorizontalMargin + xScale*i/2, kVerticalTopMargin + (maxValue - value)*yScale)];
if (i == self.datesAndValues.count - 2)
[path addArcWithCenter:CGPointMake(kLeftHorizontalMargin + xScale*i/2, kVerticalTopMargin + (maxValue - value)*yScale) radius:kPathLineWidth startAngle:0 endAngle:2*M_PI clockwise:YES];
NSDate* date = self.datesAndValues[i];
if ([self.datesOfMax containsObject:date] &&
value != maxValue)
{
UIColor* textColor = [UIColor greenColor];
NSDictionary* stringAttrs = @{ NSFontAttributeName : smallFont,
NSForegroundColorAttributeName : textColor };
NSString* maxValueString = [NSString stringWithFormat:@"%.2f", value];
NSAttributedString* attrStr = [[NSAttributedString alloc] initWithString:maxValueString
attributes:stringAttrs];
CGFloat x = kLeftHorizontalMargin + xScale*i/2;
CGRect textRect = [maxValueString boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX)
options:NSStringDrawingUsesLineFragmentOrigin
attributes:stringAttrs
context:nil];
if (x + textRect.size.width + kLeftHorizontalMargin > self.frame.size.width)
x = self.frame.size.width - textRect.size.width - kLeftHorizontalMargin;
[attrStr drawAtPoint:CGPointMake(x, (maxValue - value)*yScale)];
}
if (value == maxValue)
{
UIColor* textColor = [UIColor greenColor];
NSDictionary* stringAttrs = @{ NSFontAttributeName : bigFont,
NSForegroundColorAttributeName : textColor };
NSString* maxValueString = [NSString stringWithFormat:@"%.2f", value];
NSAttributedString* attrStr = [[NSAttributedString alloc] initWithString:maxValueString
attributes:stringAttrs];
CGRect textRect = [maxValueString boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX)
options:NSStringDrawingUsesLineFragmentOrigin
attributes:stringAttrs
context:nil];
CGFloat x = kLeftHorizontalMargin + xScale*i/2 - textRect.size.width;
if (x < kLeftHorizontalMargin)
x = kLeftHorizontalMargin;
[attrStr drawAtPoint:CGPointMake(x, kMaxValueVerticalTopMargin + (maxValue - value)*yScale)];
}
if ([self.datesOfMin containsObject:date] &&
value != minValue)
{
UIColor* textColor = [UIColor redColor];
NSDictionary* stringAttrs = @{ NSFontAttributeName : smallFont,
NSForegroundColorAttributeName : textColor };
NSString* minValueString = [NSString stringWithFormat:@"%.2f", value];
NSAttributedString* attrStr = [[NSAttributedString alloc] initWithString:minValueString
attributes:stringAttrs];
CGFloat x = kLeftHorizontalMargin + xScale*i/2;
[attrStr drawAtPoint:CGPointMake(x, kVerticalTopMargin + (maxValue - value)*yScale)];
}
if (value == minValue)
{
UIColor* textColor = [UIColor redColor];
NSDictionary* stringAttrs = @{ NSFontAttributeName : bigFont,
NSForegroundColorAttributeName : textColor };
NSString* minValueString = [NSString stringWithFormat:@"%.2f", value];
NSAttributedString* attrStr = [[NSAttributedString alloc] initWithString:minValueString
attributes:stringAttrs];
CGFloat x = kLeftHorizontalMargin + xScale*i/2;
CGRect textRect = [minValueString boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX)
options:NSStringDrawingUsesLineFragmentOrigin
attributes:stringAttrs
context:nil];
if (x + textRect.size.width + kLeftHorizontalMargin > self.frame.size.width)
x = self.frame.size.width - textRect.size.width - kLeftHorizontalMargin;
[attrStr drawAtPoint:CGPointMake(x, kVerticalTopMargin + (maxValue - value)*yScale)];
}
}
path.lineWidth = kPathLineWidth;
[[UIColor lightGrayColor] setStroke];
[path stroke];
}
最佳答案
如果self.datesAndValues中只有一对日期/值对，则代码会崩溃。
看这行:
double xScale = (self.frame.size.width - kLeftHorizontalMargin - kRightHorizontalMargin)/((self.datesAndValues.count - 1)/2);
如果
self.datesAndValues的计数为2，则xScale的结果值为+Inf，因为((self.datesAndValues.count - 1)/2)将为0。关于ios - drawRect中的SIGABRT，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/24568098/