iOS手势密码的实现方法

#define ScreenHeight [[UIScreen mainScreen] bounds].size.height#define ScreenWidth [[UIScreen mainScreen] bounds].size.width

@property (nonatomic,strong)NSMutableArray *buttonArr;//全部手势按键的数组@property (nonatomic,strong)NSMutableArray *selectorArr;//选中手势按键的数组@property (nonatomic,assign)CGPoint startPoint;//记录开始选中的按键坐标@property (nonatomic,assign)CGPoint endPoint;//记录结束时的手势坐标@property (nonatomic,strong)UIImageView *imageView;//画图所需

-(NSMutableArray *)selectorArr{  if (!_selectorArr) {    _selectorArr = [[NSMutableArray alloc]init];  }  return _selectorArr;}

- (void)viewDidLoad {  [super viewDidLoad];  self.view.backgroundColor = [UIColor whiteColor];    if (!_buttonArr) {    _buttonArr = [[NSMutableArray alloc]initWithCapacity:9];  }    self.imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, ScreenWidth, ScreenHeight)];  [self.view addSubview:self.imageView];  for (int i=0; i<3; i++) {    for (int j=0; j<3; j++) {      UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];      btn.frame = CGRectMake(ScreenWidth/12+ScreenWidth/3*j, ScreenHeight/3+ScreenWidth/3*i, ScreenWidth/6, ScreenWidth/6);      [btn setImage:[UIImage imageNamed:@"pbg"] forState:UIControlStateNormal];      [btn setImage:[UIImage imageNamed:@"pbg01"] forState:UIControlStateHighlighted];      btn.userInteractionEnabled = NO;      [self.buttonArr addObject:btn];      [self.imageView addSubview:btn];    }      }}

-(UIImage *)drawLine{  UIImage *image = nil;    UIColor *col = [UIColor colorWithRed:1 green:0 blue:0 alpha:1];  UIGraphicsBeginImageContext(self.imageView.frame.size);//设置画图的大小为imageview的大小  CGContextRef context = UIGraphicsGetCurrentContext();  CGContextSetLineWidth(context, 5);  CGContextSetStrokeColorWithColor(context, col.CGColor);    CGContextMoveToPoint(context, self.startPoint.x, self.startPoint.y);//设置画线起点  //从起点画线到选中的按键中心，并切换画线的起点  for (UIButton *btn in self.selectorArr) {    CGPoint btnPo = btn.center;    CGContextAddLineToPoint(context, btnPo.x, btnPo.y);    CGContextMoveToPoint(context, btnPo.x, btnPo.y);  }  //画移动中的最后一条线  CGContextAddLineToPoint(context, self.endPoint.x, self.endPoint.y);    CGContextStrokePath(context);    image = UIGraphicsGetImageFromCurrentImageContext();//画图输出  UIGraphicsEndImageContext();//结束画线  return image;}

//开始手势-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{  UITouch *touch = [touches anyObject];//保存所有触摸事件  if (touch) {            for (UIButton *btn in self.buttonArr) {            CGPoint po = [touch locationInView:btn];//记录按键坐标            if ([btn pointInside:po withEvent:nil]) {//判断按键坐标是否在手势开始范围内,是则为选中的开始按键                [self.selectorArr addObject:btn];        btn.highlighted = YES;        self.startPoint = btn.center;//保存起始坐标      }        }      }  }//移动中触发，画线过程中会一直调用画线方法-(void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{  UITouch *touch = [touches anyObject];  if (touch) {        self.endPoint = [touch locationInView:self.imageView];    for (UIButton *btn in self.buttonArr) {      CGPoint po = [touch locationInView:btn];      if ([btn pointInside:po withEvent:nil]) {                BOOL isAdd = YES;//记录是否为重复按键        for (UIButton *seBtn in self.selectorArr) {          if (seBtn == btn) {            isAdd = NO;//已经是选中过的按键，不再重复添加            break;          }        }        if (isAdd) {//未添加的选中按键，添加并修改状态          [self.selectorArr addObject:btn];          btn.highlighted = YES;        }              }    }  }  self.imageView.image = [self drawLine];//每次移动过程中都要调用这个方法，把画出的图输出显示  }//手势结束触发-(void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{  self.imageView.image = nil;  self.selectorArr = nil;  for (UIButton *btn in self.buttonArr) {    btn.highlighted = NO;  }}