我想以编程方式将 UIButton 完全放在贝塞尔路径上，但每次我更改路径坐标时，按钮位置都会完全改变。以下是我的代码。请帮助我将 UIbutton 准确定位在 Bezier 路径上。顺便说一句，我将 Button 放在直线路径上没有任何问题，但是当它出现对角线时，一切都搞砸了
//
// HomeViewController.m
// POCInitial
//
// Created by Hammy Usmani on 25/06/2013.
// Copyright (c) 2013 Hammy Usmani. All rights reserved.
//
#import "HomeViewController.h"
#import "RectangleView.h"
@interface HomeViewController ()
@end
@implementation HomeViewController
@synthesize drawpad;
@synthesize firstPoint, secondPoint, thirdPoint, fourthPoint;
@synthesize path;
@synthesize strokeValue;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
self.strokeValue = 15.0;
[self setPathPoint];
[self setPathForPoints];
[self clickLineOne];
[self clickLineTwo];
[self clickLineThree];
[self clickLineFour];
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma Button Function
-(void)clickLineOne
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self
action:@selector(calculateDistance:)
forControlEvents:UIControlEventTouchDown];
[button setTitle:@"" forState:UIControlStateNormal];
button.frame = CGRectMake([firstPoint.x floatValue], [firstPoint.y floatValue] - 41, [secondPoint.x floatValue] - [firstPoint.x floatValue], self.strokeValue);
button.tag = 1;
[button setBackgroundColor:[UIColor yellowColor]];
[self.view addSubview:button];
}
-(void)clickLineTwo
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self
action:@selector(calculateDistance:)
forControlEvents:UIControlEventTouchDown];
[button setTitle:@"" forState:UIControlStateNormal];
button.frame = CGRectMake([secondPoint.x floatValue], [secondPoint.y floatValue] - 41, self.strokeValue, [thirdPoint.y floatValue] - [secondPoint.y floatValue]);
button.tag = 2;
[button setBackgroundColor:[UIColor yellowColor]];
[self.view addSubview:button];
}
-(void)clickLineThree
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self
action:@selector(calculateDistance:)
forControlEvents:UIControlEventTouchDown];
[button setTitle:@"" forState:UIControlStateNormal];
double aSquare = pow(abs([fourthPoint.y floatValue] - [thirdPoint.y floatValue]), 2.0);
double bSquare = pow(abs([fourthPoint.x floatValue] - [thirdPoint.x floatValue]), 2.0);
double length = sqrt(aSquare + bSquare);
button.tag = 3;
[button setBackgroundColor:[UIColor yellowColor]];
if([thirdPoint.y floatValue] != [fourthPoint.y floatValue])
{
CGFloat angle = [self pointPairToBearingDegrees:thirdPoint secondPoint:fourthPoint];
CGAffineTransform rotationTransform = CGAffineTransformIdentity;
rotationTransform = CGAffineTransformMakeRotation(angle);
button.transform = rotationTransform;
}
button.frame = CGRectMake([thirdPoint.x floatValue], [thirdPoint.y floatValue]-41, -length, self.strokeValue);
[self.view addSubview:button];
}
-(void)clickLineFour
{
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self
action:@selector(calculateDistance:)
forControlEvents:UIControlEventTouchDown];
[button setTitle:@"" forState:UIControlStateNormal];
button.frame = CGRectMake([fourthPoint.x floatValue]-5, [fourthPoint.y floatValue]-82, self.strokeValue, -([fourthPoint.y floatValue] - [firstPoint.y floatValue])+41);
button.tag = 4;
[button setBackgroundColor:[UIColor yellowColor]];
[self.view addSubview:button];
}
-(void)calculateDistance:(id)sender
{
UIButton *button = (UIButton *)sender;
if(button.tag == 1)
{
int distance = abs([secondPoint.x floatValue] - [firstPoint.x floatValue]) +abs([secondPoint.y floatValue] - [firstPoint.y floatValue]);
UILabel *lblDistance = [[UILabel alloc] initWithFrame:CGRectMake(([secondPoint.x floatValue] + [firstPoint.x floatValue])/2, [firstPoint.y floatValue] - 41, [secondPoint.x floatValue] - [firstPoint.x floatValue], self.strokeValue)];
lblDistance.text = [NSString stringWithFormat:@"%d", distance];
lblDistance.backgroundColor = [UIColor clearColor];
lblDistance.textColor = [UIColor whiteColor];
[self.view addSubview:lblDistance];
}
else if(button.tag == 2)
{
int distance = abs([thirdPoint.x floatValue] - [secondPoint.x floatValue]) +abs([thirdPoint.y floatValue] - [secondPoint.y floatValue]);
UILabel *lblDistance = [[UILabel alloc] initWithFrame:CGRectMake([secondPoint.x floatValue]-20, [secondPoint.y floatValue] - 41, self.strokeValue+15, [thirdPoint.y floatValue] - [secondPoint.y floatValue])];
lblDistance.text = [NSString stringWithFormat:@"%d", distance];
lblDistance.backgroundColor = [UIColor clearColor];
lblDistance.textColor = [UIColor whiteColor];
[self.view addSubview:lblDistance];
}
else if(button.tag == 3)
{
double aSquare = pow(abs([fourthPoint.y floatValue] - [thirdPoint.y floatValue]), 2.0);
double bSquare = pow(abs([fourthPoint.x floatValue] - [thirdPoint.x floatValue]), 2.0);
double length = sqrt(aSquare + bSquare);
int distance = abs([fourthPoint.x floatValue] - [thirdPoint.x floatValue]) +abs([fourthPoint.y floatValue] - [thirdPoint.y floatValue]);
UILabel *lblDistance = [[UILabel alloc] initWithFrame:CGRectMake(([thirdPoint.x floatValue] + [fourthPoint.x floatValue])/2, (([thirdPoint.y floatValue] + [fourthPoint.y floatValue])/2)-90, length, self.strokeValue)];
lblDistance.text = [NSString stringWithFormat:@"%d", distance];
lblDistance.backgroundColor = [UIColor clearColor];
lblDistance.textColor = [UIColor whiteColor];
[self.view addSubview:lblDistance];
}
else
{
int distance = abs([firstPoint.x floatValue] - [fourthPoint.x floatValue]) +abs([firstPoint.y floatValue] - [fourthPoint.y floatValue]);
UILabel *lblDistance = [[UILabel alloc] initWithFrame:CGRectMake([fourthPoint.x floatValue]-5, [fourthPoint.y floatValue]-82, self.strokeValue+15, -([fourthPoint.y floatValue] - [firstPoint.y floatValue])+41)];
lblDistance.text = [NSString stringWithFormat:@"%d", distance];
lblDistance.backgroundColor = [UIColor clearColor];
lblDistance.textColor = [UIColor whiteColor];
[self.view addSubview:lblDistance];
}
}
#pragma Coordinates Functions
- (CGFloat) pointPairToBearingDegrees:(PointScreen*)startingPoint secondPoint:(PointScreen*) endingPoint
{
CGPoint originPoint = CGPointMake([endingPoint.x floatValue] - [startingPoint.x floatValue], [endingPoint.y floatValue] - [startingPoint.y floatValue]); // get origin point to origin by subtracting end from start
float bearingRadians = atan2(originPoint.y, originPoint.x); // get bearing in radians
float bearingDegrees = bearingRadians * (180.0 / M_PI); // convert to degrees
bearingDegrees = (bearingDegrees > 0.0 ? bearingDegrees : (360.0 + bearingDegrees)); // correct discontinuity
return bearingDegrees;
}
-(void)setPathPoint
{ firstPoint = [[PointScreen alloc] initWithxCoordinate:50.0 andWithyCoordinate:50.0];
secondPoint = [[PointScreen alloc] initWithxCoordinate:200.0 andWithyCoordinate:50.0];
thirdPoint = [[PointScreen alloc] initWithxCoordinate:200.0 andWithyCoordinate:200.0];
fourthPoint = [[PointScreen alloc] initWithxCoordinate:50.0 andWithyCoordinate:150.0];
}
-(void)setPathForPoints
{
self.path = [[UIBezierPath alloc] init];
[path moveToPoint:CGPointMake([firstPoint.x floatValue], [firstPoint.y floatValue])];
[path addLineToPoint:CGPointMake([secondPoint.x floatValue], [secondPoint.y floatValue])];
[path addLineToPoint:CGPointMake([thirdPoint.x floatValue], [thirdPoint.y floatValue])];
[path addLineToPoint:CGPointMake([fourthPoint.x floatValue], [fourthPoint.y floatValue])];
[path closePath];
UIGraphicsBeginImageContext(self.view.frame.size);
path.lineCapStyle = kCGLineCapRound;
path.lineWidth = 15.0f;
[[UIColor blackColor] setStroke];
[[UIColor redColor] setFill];
[path stroke];
[path fill];
self.drawpad.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
}
@end
提前致谢