这次只上一个demo，一看便知。
#import "XCViewController.h"
@interface XCViewController ()
@property (nonatomic, strong)UISlider * mySlider;
@property (nonatomic, strong)UILabel * myLabel;
@end
@implementation XCViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// 创建一个UISlider
_mySlider = [[UISlider alloc] initWithFrame:CGRectMake(0, 0, 200, 23)];
// 定位UISlider的位置
_mySlider.center = self.view.center;
// 设置UISlider的最小值和最大值
_mySlider.minimumValue = 2;
_mySlider.maximumValue = 50;
// 设置UISlider的初始值
_mySlider.value = 12;
// 为UISlider添加事件方法
[_mySlider addTarget:self action:@selector(sliderValueChanged:) forControlEvents:UIControlEventValueChanged];
// 定义UISlider的样式
_mySlider.minimumTrackTintColor = [UIColor redColor];
_mySlider.maximumTrackTintColor = [UIColor greenColor];
_mySlider.thumbTintColor = [UIColor blueColor];
// 新建一个UILabel对象
_myLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 20, 320, 50)];
// 设置这个UILabel对象的字体为系统字体，大小为当前UISlider的值
_myLabel.font = [UIFont systemFontOfSize:_mySlider.value];
_myLabel.text = @"XCoder Studio";
// 将UISlider添加到一个UIView视图中
[self.view addSubview:_mySlider];
// 将UILabel添加到一个UIView视图中
[self.view addSubview:_myLabel];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)sliderValueChanged:(id)sender {
if([sender isKindOfClass:[UISliderclass]]) {
UISlider * slider = (UISlider *)sender;
_myLabel.font = [UIFont systemFontOfSize:slider.value];
}
}
@end
