效果图

项目结构

常量的定义

//const 定义 只读的变量名，在其他的类中不能声明同样的变量名
CGFloat const btnCount = 9;

// define只是字符的转换
#define kScreenWidth [UIScreen mainScreen].bounds.size.width

UIView的两种init方法

//通过代码创建会调用这个方法
- (instancetype)initWithFrame:(CGRect)frame{
if (self = [super initWithFrame:frame]) {
    [self AddButton];
}
return self;
}

//通过storyboard 或者 xib 文件创建的时候会调用
-(id)initWithCoder:(NSCoder *)aDecoder{
if (self = [super initWithCoder:aDecoder]) {
    [self AddButton];
}
return self;
}

常用插件

在github上查找，然后下载，完成之后运行

KSImageNamed
VVDocumenter-Xcode
ColorSense-for-Xcode-master

触摸方法

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{}

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{}

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{}

-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event{
[self touchesEnded:touches withEvent:event];
}

触摸点的坐标

UITouch *touch = [touches anyObject];
CGPoint point = [touch locationInView:self];

触摸的按钮

- (UIButton *)buttonWithPoint:(CGPoint)point{
for (UIButton *btn in self.subviews) {
    if (CGRectContainsPoint(btn.frame, point)) {
        return btn;
    }
}
return nil;
}

点是否在指定CGRect内

bool CGRectContainsPoint (
    CGRect rect,
    CGPoint point
);

.m 里声明私有属性

//匿名扩展（类目的特例） ：可以声明属性,私有的
@interface JKLockView ()
@property (nonatomic, strong) NSMutableArray *selectedBtns;
@property (nonatomic, assign) CGPoint currentPoint;
@end

数组或字典添加对象需要先判断

if (btn) {
[self.selectedBtns addObject:btn];
}

开始绘图

[self setNeedsDisplay];

绘制贝塞尔曲线

UIBezierPath *path = [UIBezierPath bezierPath];
path.lineWidth = 8;
path.lineJoinStyle = kCGLineJoinRound;
[[UIColor colorWithRed:32/255.0 green:210/255.0 blue:254/255.0 alpha:0.5] set];

//遍历按钮
for (int i = 0; i < self.selectedBtns.count; i++) {
    UIButton *button = self.selectedBtns[i];
    if (i == 0) {

        //设置起点
        [path moveToPoint:button.center];

    }else{//连线

        [path addLineToPoint:button.center];
    }
}

[path addLineToPoint:self.currentPoint];
[path stroke];

数组中每个对象执行某方法

//makeObjectsPerformSelector  
//每个按钮设为没有选中状态
//向数组中的每一个对象发送方法 setSelected:，方法参数为 NO
[self.selectedBtns makeObjectsPerformSelector:@selector(setSelected:) withObject:NO];

IBOutlet 和 delegate连接

@property (nonatomic, assign) IBOutlet id<JKLockViewDelegate> delegate;

UIAlertController

UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"密码正确" message:nil preferredStyle:UIAlertControllerStyleAlert];
[alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDestructive handler:nil]];
[alert addAction:[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil]];
[self presentViewController:alert animated:YES completion:nil];

连接字符串

[path appendFormat:@"%ld",(long)btn.tag];