iOS手写签名

前段时间有个朋友让帮忙写一个手写签名的功能,自己利用业余时间做了一下也算复习了下基础知识,现在整理出来写到上;
关于手写签名,我先是找了下别人的博客,有一个写的就很好,我把地址贴出来,大家可以参考一下
IOS:手写签名的实现实现了手势绘制字体,添加文字水印,图片剪切、图片压缩
主要是我的需求比较简单,看着人家写的这么详细 不忍心抄写,所以决定自己写,先上效果图:
iOS手写签名
文章图片
手写签名效果图.gif 我的思路是,在控制器中添加一个自定义的签名的View:signatureView,再设置一个重签的按钮用来清除重写,一个确认的按钮,将签名保存下来;

iOS手写签名
文章图片
签名页面.png
页面比较简单,为了少写一些成员变量,我把布局也写在了ViewDidLoad中
1、页面布局的代码如下:
1.1 页面布局

self.view.backgroundColor = [UIColor grayColor]; self.signatureView = [[signatureView alloc]initWithFrame:CGRectMake(10, 70, self.view.width - 20, (self.view.width - 20)*0.4)]; self.signatureView.backgroundColor = [UIColor whiteColor]; self.signatureView.color = [UIColor blackColor]; self.signatureView.lineWidth = 2; [self.view addSubview:self.signatureView]; UIButton *reSignBtn = [UIButton buttonWithType:UIButtonTypeCustom]; [reSignBtn setTitle:@"重签" forState:UIControlStateNormal]; [reSignBtn setTitleColor:[UIColor redColor] forState:UIControlStateNormal]; [reSignBtn setFrame:CGRectMake(20, CGRectGetMaxY(self.signatureView.frame)+10, (self.view.width - 20*3)*0.5, 40)]; reSignBtn.layer.cornerRadius = 5.0; reSignBtn.clipsToBounds = YES; reSignBtn.layer.borderWidth = 1.0; reSignBtn.titleLabel.font = [UIFont systemFontOfSize:17]; [reSignBtn addTarget:self action:@selector(clear:) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:reSignBtn]; UIButton *confirmBtn = [UIButton buttonWithType:UIButtonTypeCustom]; [confirmBtn setTitle:@"确认" forState:UIControlStateNormal]; [confirmBtn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal]; confirmBtn.titleLabel.font = [UIFont systemFontOfSize:17.0]; confirmBtn.backgroundColor = [UIColor greenColor]; confirmBtn.frame = CGRectMake(CGRectGetMaxX(reSignBtn.frame)+20, reSignBtn.y, reSignBtn.width, reSignBtn.height); confirmBtn.layer.cornerRadius = 5.0; confirmBtn.clipsToBounds = YES; [confirmBtn addTarget:self action:@selector(confirmBtnClick:) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:confirmBtn];

1.2 两个按钮的方法:
// 清除按钮方法 -(void)clear:(UIButton *)btn{[self.signatureView clearScreen]; } // 确定按钮方法 -(void)confirmBtnClick:(UIButton *)btn { NSLog(@"确定保存"); // 开启位图上下文 UIGraphicsBeginImageContextWithOptions(_signatureView.bounds.size, NO, 0); // 获取当前位图上下文 CGContextRef ctx = UIGraphicsGetCurrentContext(); // 截屏内容到上下文 [_signatureView.layer renderInContext:ctx]; // 获取图片 UIImage *img = UIGraphicsGetImageFromCurrentImageContext(); // 关闭上下文 UIGraphicsEndImageContext(); // 这里拿到签名后的图片,可以保存到相册 // 保存到手机相册 UIImageWriteToSavedPhotosAlbum(img, self, @selector(image:didFinishSavingWithError:contextInfo:), nil); // 我这里是通过block传值给上一个页面 if (self.signBlock) { self.signBlock(img); } [self.navigationController popViewControllerAnimated:YES]; }

如果保存到相册,回调方法:
// 保存相册成功之后的回调方法 - (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo { if (error) { NSLog(@"保存成功"); // [MBProgressHUD showError:@"保存失败"]; }else{ // 保存成功 NSLog(@"保存失败"); //[MBProgressHUD showSuccess:@"保存成功"]; } }```###2. signatureView 首先重写initWithFrame: 设置默认的lineWidth 和color,我们把lineWidth和color设置成属性,暴露到.h头文件中,方便控制器中修改;

-(instancetype)initWithFrame:(CGRect)frame {
if (self = [super initWithFrame:frame]){
_lineWidth = 1;
_color = [UIColor blackColor];
}
return self;
}
我们在touchesBegan: 和touchesMoved: 中创建和绘制UIBezierPath 路径

  • (CGPoint)pointWithTouches:(NSSet *)touches
    {
    // 获取touch对象
    UITouch *touch = [touches anyObject];
    // 获取当前触摸点
    return [touch locationInView:self];
    }
    -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    CGPoint curP = [self pointWithTouches:touches];
    // 创建路径
    DrawPath *path = [DrawPath pathWitchColor:_color lineWidth:_lineWidth];
    [path moveToPoint:curP];
    _path = path;
    [self.paths addObject:path];
    }
    -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
    CGPoint curP = [self pointWithTouches:touches];
    [_path addLineToPoint:curP];
    [self setNeedsDisplay];
}
上面的DrawPath 是继承自UIBezierPath 的子类,为了给UIBezierPath拓展color属性

  • (instancetype)pathWitchColor:(UIColor *)color lineWidth:(CGFloat)lineWidth
    {
    DrawPath *path = [[self alloc] init];
    path.color = color;
    path.lineWidth = lineWidth;
    return path;
    }
绘制完成后调用 [self setNeedsDisplay] 系统会调用 drawRect:方法完成绘制

-(void)drawRect:(CGRect)rect{
if (self.paths.count == 0) {
return;
}
for (DrawPath *path in self.paths) {
[path.color set];
[path stroke];
}
}
另外的清屏操作和懒加载代码如下:

// 清屏
  • (void)clearScreen
    {
    // 清空所有的路径
    [self.paths removeAllObjects];
    [self setNeedsDisplay];
    }
    // 懒加载
    -(NSMutableArray *)paths{
    if (!_path) {
    _paths = [NSMutableArray array];
    }
    return _paths;
【iOS手写签名】}
如此我们就用绘图的方法 简单实现了手写签名功能;

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