iOS实现刻度尺，可移动刻度尺，并取得当前对应的刻度值。
本文章，技术意义不大，主要是我想写个文章让特定的人知道我做过iOS开发；
这是以前项目里的代码，直接拿出来！
要做的功能如图：
下面是代码：
KADRuler.h
#import <UIKit/UIKit.h>
@interface KADRuler : UIView
-(instancetype)initWithFrame:(CGRect)frame fromNumber:(NSInteger)fromNum toNumber:(NSInteger)toNum;
///左边或者右边的空白
@property(nonatomic, assign, readonly)CGFloat sideSpace;
///根据刻度值取它的偏移
-(CGFloat)getScaleOffsetByNumber:(NSInteger)number;
///根据偏移取对应的刻度值
-(NSInteger)getNumberByOffset:(CGFloat)offsetX;
@endKADRuler.m
#import "KADRuler.h"
@interface KADRuler()
{
NSInteger startNum, endNum;
CGFloat space, lrSpace;
}
@end
@implementation KADRuler
-(instancetype)init
{
CGRect frame = CGRectMake(0, 0, W_WIDTH, 50);
return [self initWithFrame:frame];
}
-(instancetype)initWithFrame:(CGRect)frame
{
return [self initWithFrame:frame fromNumber:0 toNumber:100];
}
-(instancetype)initWithFrame:(CGRect)frame fromNumber:(NSInteger)fromNum toNumber:(NSInteger)toNum
{
space = 8.0;
lrSpace = space*3;
startNum = fromNum;
endNum = toNum;
if (endNum<startNum) {
startNum = 0;
endNum = 100;
}
if(frame.size.height<=0){ frame.size.height = 50; }
frame.size.width = (endNum-startNum)*space + lrSpace*2;
self = [super initWithFrame:frame];
if (self) {
self.backgroundColor = [UIColor whiteColor];
}
return self;
}
-(CGFloat)sideSpace
{
return lrSpace;
}
-(CGFloat)getScaleOffsetByNumber:(NSInteger)number
{
if (number<startNum) {
return 0;
}
CGFloat x = lrSpace + space*(number-startNum);
return x;
}
-(NSInteger)getNumberByOffset:(CGFloat)offsetX
{
offsetX += 0.05; //增加偏移补偿量，如不增加，则在4/5/5s/6Plus会有边界值显示错误bug
NSInteger num = (offsetX - lrSpace)/space + startNum;
return num;
}
-(void)drawRect:(CGRect)rect
{
CGFloat r,g,b,a;
UIColor *color = [UIColor colorWithRgbToUIColor:@"898989"];
[color getRed:&r green:&g blue:&b alpha:&a];
CGContextRef context = UIGraphicsGetCurrentContext();
// 设置线的粗细
CGContextSetLineWidth(context, 1.0);
CGFloat x = lrSpace, y=0;
//设置字体
UIFont *font = [UIFont systemFontOfSize:13.0];
for (long i=startNum; i<=endNum; i++) {
// 设置线的颜色及透明度
CGContextSetRGBStrokeColor(context, r, g, b, a);
// 开始点
CGContextMoveToPoint(context, x, 0.0);
//结束点
y = i%5==0?25:15;
CGContextAddLineToPoint(context, x, y); //22
//开始一条线
CGContextStrokePath(context);
//
if (i%10==0) {
//设置矩形填充颜色：红色
CGContextSetRGBFillColor (context, 34.0/255.0, 34.0/255.0, 34.0/255.0, 1.0);
//在指定的矩形区域内画文字
NSString *num = [NSString stringWithFormat:@"%ld", i];
CGSize size = [num sizeWithFont:font];
[num drawInRect:CGRectMake(x-size.width/2-0.5, y+3, size.width, size.height) withFont:font];
}
//
x += space;
}
}
@endKADRulerControl.h
#import "KADUIControl.h"
@interface KADRulerControl : KADUIControl
///自定义范围初始化
-(instancetype)initWithFrame:(CGRect)frame fromNumber:(NSInteger)fromNum toNumber:(NSInteger)toNum;
///当前刻度值
@property (nonatomic, assign)NSInteger SelectedScale;
///最小可用刻度
@property(nonatomic, assign)NSInteger minNumber;
///最大可用刻度
@property(nonatomic, assign)NSInteger maxNumber;
@endKADRulerControl.m
#import "KADRulerControl.h"
#import "KADRuler.h"
@interface KADRulerControl()<UIScrollViewDelegate>
{
UIScrollView *_scro;
KADRuler *ruler;
NSInteger selectedNumber;
NSInteger startNum, endNum;
BOOL isBusy;
}
@end
@implementation KADRulerControl
-(instancetype)init
{
CGRect frame = CGRectMake(0, 0, W_WIDTH, 50);
return [self initWithFrame:frame];
}
-(instancetype)initWithFrame:(CGRect)frame
{
return [self initWithFrame:frame fromNumber:0 toNumber:100];
}
-(instancetype)initWithFrame:(CGRect)frame fromNumber:(NSInteger)fromNum toNumber:(NSInteger)toNum
{
if (toNum<fromNum) {
fromNum = 0;
toNum = 100;
}
self = [super initWithFrame:frame];
if (self) {
self.minNumber = fromNum;
self.maxNumber = toNum;
_scro = [[UIScrollView alloc] init];
_scro.frame = self.bounds;
_scro.bounces = NO;
_scro.showsHorizontalScrollIndicator = NO;
_scro.showsVerticalScrollIndicator = NO;
_scro.delegate = self;
_scro.backgroundColor = [UIColor clearColor];
_scro.pagingEnabled = NO;
[self addSubview:_scro];
//
startNum = fromNum-50;
endNum = toNum+50;
ruler = [[KADRuler alloc]initWithFrame:frame fromNumber:startNum toNumber:endNum];
[_scro addSubview:ruler marginLeft:0 marginTop:0];
[_scro setContentSizeWidth:ruler.width];
//
[self addSubview:[self createHLine] marginTop:0];
selectedNumber = (toNum-fromNum)/2;
self.SelectedScale = selectedNumber;
}
return self;
}
-(void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat offsetX = scrollView.contentOffset.x;
selectedNumber = [ruler getNumberByOffset:offsetX + (_scro.width/2.0)];
//限制最小和最大值
if(selectedNumber<self.minNumber){
scrollView.decelerationRate = 0.0;
scrollView.scrollEnabled = NO;
CGFloat x = [ruler getScaleOffsetByNumber:self.minNumber];
x -= (_scro.width/2.0);
CGPoint offset = scrollView.contentOffset;
offset.x = x;
[scrollView setContentOffset:offset animated:NO];
scrollView.scrollEnabled = YES;
scrollView.decelerationRate = UIScrollViewDecelerationRateNormal;
}else if(selectedNumber>self.maxNumber){
scrollView.decelerationRate = 0.0;
scrollView.scrollEnabled = NO;
CGFloat x = [ruler getScaleOffsetByNumber:self.maxNumber];
x -= (_scro.width/2.0);
CGPoint offset = scrollView.contentOffset;
offset.x = x;
//scrollView.contentOffset = offset;//不能马上停止
[scrollView setContentOffset:offset animated:NO];//可马上停止
scrollView.scrollEnabled = YES;
scrollView.decelerationRate = UIScrollViewDecelerationRateNormal;
}
[self ExecActionBlock:self andTag:selectedNumber andData:nil];
}
-(NSInteger)SelectedScale
{
return selectedNumber;
}
-(void)setSelectedScale:(NSInteger)SelectedScale
{
selectedNumber = SelectedScale;
CGFloat offsetX = [ruler getScaleOffsetByNumber:selectedNumber];
offsetX -= (_scro.width/2.0);
[_scro setContentOffsetX:offsetX];
}
-(UIView*)createHLine
{
UIView *v = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 1, 58)];
v.backgroundColor = [UIColor colorWithRgbToUIColor:@"fc2d2d"];
return v;
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
// Drawing code
}
*/
@end
KADBMICalculatorVC.m
//
// KADBMICalculatorVC.m
// KADOnlinePharmacies
//
// Created by envon on 15-4-25.
// Copyright (c) 2015年 360KAD. All rights reserved.
//
#import "KADBMICalculatorVC.h"
#import "KADRulerControl.h"
#import "KADBMIResultVC.h"
#import "KADGuidePageService.h"
@interface KADBMICalculatorVC ()<UIScrollViewDelegate>
{
CGFloat startY;
UIScrollView *_scro;
UILabel *labN2,*labN1;
KADRulerControl *ruler1,*ruler2;
}
@end
@implementation KADBMICalculatorVC
- (void)viewDidLoad {
[super viewDidLoad];
startY = [super getStartY];
self.view.backgroundColor = [UIColor colorWithRgbToUIColor:@"eeeeee"];
KADNavigationBar *navBar = [super setNavigationBarWithTitle:@"BMI计算器" andHasBackButton:YES];
[navBar.contentView addSubview:[self createLine] marginLeft:0 marginBottom:0];
__weak KADBMICalculatorVC *me = self;
CGFloat space = Fit750(20);
//=========== 右上角“更多”选项按钮
UIButton *rightBarBtn = [super createRMenuWithTag:222];
rightBarBtn.backgroundColor = [UIColor clearColor];
[navBar.contentView addSubview:rightBarBtn];
_scro = [[UIScrollView alloc] init];
_scro.frame = CGRectMake(0, startY, W_WIDTH, self.view.height-startY);
_scro.bounces = NO;
_scro.showsHorizontalScrollIndicator = NO;
_scro.showsVerticalScrollIndicator = NO;
_scro.delegate = self;
_scro.backgroundColor = [UIColor clearColor];
[self.view addSubview:_scro];
/**
*
* 身高
*/
/** 默认身高 */
NSInteger defaultHeight = 170;
UIView *v1 = [[UIView alloc]initWithFrame:CGRectMake(0, 0, Fit750(750), Fit750(290))];
v1.backgroundColor = [UIColor whiteColor];
[_scro addSubview:v1 marginLeft:0 marginTop:space];
ruler1 = [[KADRulerControl alloc]initWithFrame:CGRectMake(0, 0, W_WIDTH-2*space, Fit750(180)) fromNumber:30 toNumber:300];
ruler1.layer.borderColor = [UIColor colorWithRgbToUIColor:@"cbcbcb"].CGColor;
ruler1.layer.borderWidth = KAD_ONE_POINT_WIDTH;
ruler1.SelectedScale = defaultHeight;
[ruler1 setActionBlock:^(id handle, NSInteger tag, id data) {
[me setN1:tag];
}];
[v1 addSubview:ruler1 marginLeft:space marginBottom:space];
//
UILabel *lab11 = [UILabel labelWithFrame:CGRectZero text:@"身高" fontSize:14 textRgbColor:@"222222" bgRgbColor:@"clear" align:NSTextAlignmentCenter];
UILabel *lab12 = [UILabel labelWithFrame:CGRectZero text:@"CM" fontSize:14 textRgbColor:@"222222" bgRgbColor:@"clear" align:NSTextAlignmentCenter];
[lab11 autoSizeWithFont]; [lab12 autoSizeWithFont];
[v1 addSubview:lab11 marginLeft:space marginTop:Fit750(44)];
[v1 addSubview:lab12 marginRight:space marginTop:Fit750(44)];
//
labN1 = [UILabel labelWithFrame:CGRectZero text:[NSString stringWithFormat:@"%zd",defaultHeight] fontSize:14 textRgbColor:@"2d8ff3" bgRgbColor:@"clear" align:NSTextAlignmentCenter];
labN1.font = [UIFont boldSystemFontOfSize:16];
[labN1 autoSizeWithFont];
[v1 addSubview:labN1 marginTop:Fit750(40)];
/**
*
* 体重
*/
/** 默认体重 */
NSInteger defaultWeight = 70;
UIView *v2 = [[UIView alloc]initWithFrame:CGRectMake(0, 0, Fit750(750), Fit750(290))];
v2.backgroundColor = [UIColor whiteColor];
[_scro addSubview:v2 atBottomFrame:v1.frame top:space left:0];
ruler2 = [[KADRulerControl alloc]initWithFrame:CGRectMake(0, 0, W_WIDTH-2*space, Fit750(180)) fromNumber:0 toNumber:300];
ruler2.layer.borderColor = [UIColor colorWithRgbToUIColor:@"cbcbcb"].CGColor;
ruler2.layer.borderWidth = KAD_ONE_POINT_WIDTH;
ruler2.SelectedScale = defaultWeight;
[ruler2 setActionBlock:^(id handle, NSInteger tag, id data) {
[me setN2:tag];
}];
[v2 addSubview:ruler2 marginLeft:space marginBottom:space];
//
UILabel *lab21 = [UILabel labelWithFrame:CGRectZero text:@"体重" fontSize:14 textRgbColor:@"222222" bgRgbColor:@"clear" align:NSTextAlignmentCenter];
UILabel *lab22 = [UILabel labelWithFrame:CGRectZero text:@"KG" fontSize:14 textRgbColor:@"222222" bgRgbColor:@"clear" align:NSTextAlignmentCenter];
[lab21 autoSizeWithFont]; [lab22 autoSizeWithFont];
[v2 addSubview:lab21 marginLeft:space marginTop:Fit750(44)];
[v2 addSubview:lab22 marginRight:space marginTop:Fit750(44)];
//
labN2 = [UILabel labelWithFrame:CGRectZero text:[NSString stringWithFormat:@"%zd",defaultWeight] fontSize:14 textRgbColor:@"2d8ff3" bgRgbColor:@"clear" align:NSTextAlignmentCenter];
labN2.font = [UIFont boldSystemFontOfSize:16];
[labN2 autoSizeWithFont];
[v2 addSubview:labN2 marginTop:Fit750(40)];
/**
*
* 计算按钮
*/
UIButton *btnCount = [UIButton buttonWithFrame:CGRectMake(0, 0,Fit750(709) ,Fit750(88)) Title:@"马上计算" titleFont:[UIFont systemFontOfSize:Fit320(15)] titleColor:[UIColor whiteColor] bgColor:[UIColor colorWithRgbToUIColor:@"2d8ff3"] borderWith:0 borderColor:[UIColor clearColor] cornerRadius:4];
[btnCount addTarget:self action:@selector(tapCount) forControlEvents:UIControlEventTouchUpInside];
[_scro addSubview:btnCount atBottomFrame:v2.frame top:space];
/**
*
* 底部提示框
*/
UIView *tips = [[UIView alloc]initWithFrame:CGRectMake(0, 0, Fit750(709), 80)];
tips.backgroundColor = [UIColor colorWithRgbToUIColor:@"fafafa"];
tips.layer.cornerRadius = 3;
[_scro addSubview:tips atBottomFrame:btnCount.frame top:space left:0];
NSString *str = @"<font color='#898989'><b>BMI科普：</b><br>BMI指数（身体质量指数，简称体质指数又称体重指数，英文为Body Mass Index，简称BMI），是用体重公斤数除以身高米数平方得出的数字，是目前国际上常用的衡量人体胖瘦程度以及是否健康的一个标准。备注：BMI计算适用于成人（18岁以上），不包括运动员及孕产妇。</font>";
RTLabel *rtLabel = [[RTLabel alloc] initWithFrame:CGRectMake( 0,0 ,tips.width-space*2, 0)];
// rtLabel.lineSpacing = Fit320(8);
[rtLabel setText:str];
rtLabel.font = [UIFont systemFontOfSize:Fit320(12)];
[rtLabel fitSize];
[tips addSubview:rtLabel marginLeft:space marginTop:space];
[tips setHeight:CGRectGetMaxY(rtLabel.frame) + space];
[_scro setContentSizeHeight:CGRectGetMaxY(tips.frame) + 20];
}
-(void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
//引导页
[KADGuidePageService showInViewController:self];
}
///点击计算按钮
-(void)tapCount
{
NSInteger num1 = ruler1.SelectedScale;//身高
NSInteger num2 = ruler2.SelectedScale;//体重
//=========== 测试用提醒
// [self alertShow:[NSString stringWithFormat:@"身高：%ld, 体重：%ld",num1, num2]];
KADBMIResultVC *bmiResult = [[KADBMIResultVC alloc]init];
bmiResult.num1 = num1;
bmiResult.num2 = num2;
bmiResult.backAnimated = YES;
bmiResult.hidesBottomBarWhenPushed = YES;
[self.navigationController pushViewController:bmiResult animated:YES];
}
-(void)setN1:(NSInteger)number
{
CGPoint p = labN1.center;
labN1.text = [NSString stringWithFormat:@"%ld", (long)number];
[labN1 autoSizeWithFont];
labN1.center = p;
}
-(void)setN2:(NSInteger)number
{
CGPoint p = labN2.center;
labN2.text = [NSString stringWithFormat:@"%ld", (long)number];
[labN2 autoSizeWithFont];
labN2.center = p;
}
-(UIView*)createLine
{
UIView *imgV = [[UIView alloc]initWithFrame:CGRectMake(0, 0, Fit1125(1125), KAD_ONE_POINT_WIDTH)];
imgV.backgroundColor = [UIColor colorWithRgbToUIColor:@"cbcbcb"];
return imgV;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
/*
#pragma mark - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
}
*/
@end-----------------------------------END
