1、绘制手势锁

• 具体实现代码见 GitHub 源码 QExtension

• QTouchLockView.h

      @interface QTouchLockView : UIView
  
      /// 提示信息框
      @property (nonatomic, strong) UILabel *alertLabel;
  
      /**
       *  创建手势锁视图控件，获取滑动手势结果
       *
       *  @param frame    手势锁视图控件的位置尺寸
       *  @param result   滑动手势结果，YES 成功，NO 失败
       *
       *  @return 手势锁视图控件
       */
      + (instancetype)q_touchLockViewWithFrame:(CGRect)frame
                                    pathResult:(void (^)(BOOL isSucceed, NSString *result))result;
  
      @end

• QTouchLockView.m

      #import "NSString+Hash.h"
  
      @interface QTouchLockView ()
  
      /// 存放选中的按钮
      @property (nonatomic, strong) NSMutableArray *selectedArray;
  
      /// 当前被选中的按钮
      @property (nonatomic, assign) CGPoint currentPoint;
  
      /// 滑动手势结果
      @property (nonatomic, copy) void (^resultBlock)(BOOL, NSString *);
  
      @end
  
      @implementation QTouchLockView
  
      /// 创建手势锁界面，获取滑动结果
      + (instancetype)q_touchLockViewWithFrame:(CGRect)frame
                                    pathResult:(void (^)(BOOL isSucceed, NSString *result))result {
  
          QTouchLockView *touchLockView = [[self alloc] init];
  
          CGRect tmpFrame = frame;
          tmpFrame.size.height = frame.size.width;
  
          touchLockView.frame = tmpFrame;
          touchLockView.resultBlock = result;
  
          return touchLockView;
      }
  
      /// 初始化界面
      - (instancetype)initWithFrame:(CGRect)frame {
  
          if (self = [super initWithFrame:frame]) {
  
              self.backgroundColor = [UIColor whiteColor];
  
              // 添加提示信息框
              self.alertLabel = [[UILabel alloc] init];
              self.alertLabel.textAlignment = NSTextAlignmentCenter;
              self.alertLabel.textColor = [UIColor redColor];
              self.alertLabel.backgroundColor = [UIColor clearColor];
              self.alertLabel.numberOfLines = 1;
              self.alertLabel.adjustsFontSizeToFitWidth = YES;
              [self addSubview:self.alertLabel];
  
              // 添加按钮
              for (int i = 0; i < 9; i++){
  
                  UIButton *btn = [[UIButton alloc] init];
  
                  NSString *bundlePath = [[[NSBundle mainBundle] resourcePath]
                                          stringByAppendingPathComponent:@"QTouchLockView.bundle"];
  
                  UIImage *normalImage = [UIImage imageWithContentsOfFile:
                                          [bundlePath stringByAppendingPathComponent:@"gesture_node_normal"]];
                  UIImage *selectedImage = [UIImage imageWithContentsOfFile:
                                            [bundlePath stringByAppendingPathComponent:@"gesture_node_selected"]];
                  UIImage *highlightedImage = [UIImage imageWithContentsOfFile:
                                               [bundlePath stringByAppendingPathComponent:@"gesture_node_highlighted"]];
  
                  [btn setBackgroundImage:normalImage forState:UIControlStateNormal];
                  [btn setBackgroundImage:selectedImage forState:UIControlStateSelected];
                  [btn setBackgroundImage:highlightedImage forState:UIControlStateHighlighted];
  
                  // 设置 tag 值，设置按钮对应的密码值
                  btn.tag = i + 1;
  
                  // 关闭按钮的交互，响应触摸事件
                  btn.userInteractionEnabled = NO;
  
                  [self addSubview:btn];
              }
          }
          return self;
      }
  
      /// 布局控件
      - (void)layoutSubviews {
          [super layoutSubviews];
  
          // 设置按钮的 frame
          for (int i = 0; i < self.subviews.count - 1; i++) {
  
              // 列数
              NSInteger cols = 3;
  
              // 设置按钮尺寸
              CGFloat W = self.bounds.size.width;
              CGFloat H = self.bounds.size.height;
              CGFloat btnW = W / 5;
              CGFloat btnH = H / 5;
  
              // 计算按钮的 x 坐标值
              NSUInteger col = i % cols;
              CGFloat btnX = col * btnW * 2;
  
              // 计算按钮的 y 坐标值
              NSUInteger row = i / cols;
              CGFloat btnY = row * btnH * 2;
  
              // 设置按钮的 frame
              UIButton *btn = self.subviews[i + 1];
              btn.frame = CGRectMake(btnX, btnY, btnW, btnH);
          }
  
          // 设置提示信息框的 frame
          self.alertLabel.frame = CGRectMake(0, -50, self.bounds.size.width, 30);
      }
  
      /// 触摸开始
      - (void)touchesBegan:(NSSet *)touches withEvent:(nullable UIEvent *)event {
  
          // 获取触摸起始点位置
          CGPoint startPoint = [touches.anyObject locationInView:self];
  
          // 获取其 button
          UIButton *button = nil;
          for (UIButton *btn in self.subviews) {
  
              // 设置触摸按钮的灵敏度
              CGRect frame = btn.frame;
              CGRect tmpFrame = CGRectMake(frame.origin.x + frame.size.width / 4,
                                           frame.origin.y + frame.size.height / 4,
                                           frame.size.width / 2,
                                           frame.size.height / 2);
  
              // 判断某点在不在其 frame 上
              if (CGRectContainsPoint(tmpFrame, startPoint)) {
                  button = btn;
              }
          }
  
          // 选中此 button
          if (button && button.selected == NO) {
              button.selected = YES;
              [self.selectedArray addObject:button];
          }
      }
  
      /// 触摸移动
      - (void)touchesMoved:(NSSet *)touches withEvent:(nullable UIEvent *)event {
  
          // 获取触摸点位置
          CGPoint touchPoint = [touches.anyObject locationInView:self];
  
          // 获取其 button
          UIButton *button = nil;
          for (UIButton *btn in self.subviews) {
  
              // 设置触摸按钮的灵敏度
              CGRect frame = btn.frame;
              CGRect tmpFrame = CGRectMake(frame.origin.x + frame.size.width / 4,
                                           frame.origin.y + frame.size.height / 4,
                                           frame.size.width / 2,
                                           frame.size.height / 2);
  
              // 判断某点在不在其 frame 上
              if (CGRectContainsPoint(tmpFrame, touchPoint)) {
                  button = btn;
              }
          }
  
          // 选中此 button
          if (button && button.selected == NO) {
              button.selected = YES;
              [self.selectedArray addObject:button];
          } else {
              self.currentPoint = touchPoint;
          }
  
          // 刷新视图
          [self setNeedsDisplay];
      }
  
      /// 触摸结束
      - (void)touchesEnded:(NSSet *)touches withEvent:(nullable UIEvent *)event {
  
          if (self.selectedArray.count < 4) {
  
              // 触摸点数过少
              if (self.resultBlock) {
                  self.resultBlock(NO, @"请至少连续连接四个点");
              }
  
              for (UIButton *btn in self.selectedArray) {
  
                  btn.highlighted = YES;
                  btn.selected = NO;
              }
  
              // 延迟
              dispatch_after(dispatch_time(DISPATCH_TIME_NOW,
                                           (int64_t)(0.5 * NSEC_PER_SEC)),
                             dispatch_get_main_queue(), ^{
  
                                 [self clearPath];
                             });
  
          } else {
  
              // 触摸完成
              if (self.resultBlock) {
  
                  // 获取触摸结果
                  NSMutableString *path = [NSMutableString string];
                  for (UIButton *btn in self.selectedArray) {
                      [path appendFormat:@"%ld", btn.tag];
                  }
  
                  // 对滑动获取的密码值进行 MD5 加密
                  NSString *md5Path = [path q_md5String];
  
                  self.resultBlock(YES, md5Path);
              }
  
              [self clearPath];
          }
      }
  
      /// 触摸取消
      - (void)touchesCancelled:(NSSet *)touches withEvent:(nullable UIEvent *)event {
  
          [self touchesEnded:touches withEvent:event];
      }
  
      /// 绘制贝塞尔连接线
      - (void)drawRect:(CGRect)rect {
  
          if (self.selectedArray.count == 0) {
              return;
          }
  
          UIBezierPath *path = [UIBezierPath bezierPath];
          path.lineWidth = 5;
          path.lineJoinStyle = kCGLineCapRound;
          [[UIColor colorWithRed:1 green:0 blue:0 alpha:0.5] set];
  
          for (int i = 0; i < self.selectedArray.count; i++) {
  
              UIButton *btn = self.selectedArray[i];
  
              // 如果是第一个按钮，则将其曲线的起点放在其按钮上，否则则进行连线
              if (i == 0) {
                  [path moveToPoint:btn.center];
              } else {
                  [path addLineToPoint:btn.center];
              }
          }
  
          // 如果不满足上述条件，按钮不存在则连接到临时点
          [path addLineToPoint:self.currentPoint];
          [path stroke];
      }
  
      /// 清除连接线
      - (void)clearPath {
  
          // 取消选中按钮
          for (UIButton *btn in self.selectedArray) {
              btn.highlighted = NO;
              btn.selected = NO;
          }
  
          // 清空选中按钮
          [self.selectedArray removeAllObjects];
  
          // 刷新视图
          [self setNeedsDisplay];
      }
  
      /// 懒加载
      - (NSMutableArray *)selectedArray {
          if (_selectedArray == nil) {
              _selectedArray = [NSMutableArray array];
          }
          return _selectedArray;
      }
  
      @end

• ViewController.m

      // 设置 frame
      CGFloat margin = 50;
      CGFloat width = self.view.bounds.size.width - margin * 2;
      CGRect frame = CGRectMake(margin, 200, width, width);
  
      // 创建手势锁视图界面，获取滑动结果
      QTouchLockView *touchLockView = [QTouchLockView q_touchLockViewWithFrame:frame
                                                                    pathResult:^(BOOL isSucceed, NSString * _Nonnull result) {
  
          // 处理手势触摸结果
          [self dealTouchResult:result isSucceed:isSucceed];
      }];
  
      [self.view addSubview:touchLockView];
  
      - (void)dealTouchResult:(NSString *)result isSucceed:(BOOL)isSucceed {
  
          // 处理手势触摸结果
  
          if (isSucceed) {
  
              // 判读密码是否存在
              NSUserDefaults *df = [NSUserDefaults standardUserDefaults];
  
              if ([df objectForKey:@"touchLock"] == nil) {
  
                  // 设置手势锁
  
                  [self.passWordArrM addObject:result];
  
                  if (self.passWordArrM.count == 1) {
                      self.touchLockView.alertLabel.text = @"请再设置一次";
                  }
  
                  if (self.passWordArrM.count == 2) {
                      if ([self.passWordArrM[0] isEqualToString:self.passWordArrM[1]]) {
  
                          // 存储密码
                          [df setValue:self.passWordArrM[0] forKey:@"touchLock"];
                          [df synchronize];
  
                          self.touchLockView.alertLabel.text = @"手势密码设置成功";
  
                      } else {
  
                          // 两次滑动结果不一致
                          [self.passWordArrM removeAllObjects];
  
                          self.touchLockView.alertLabel.text = @"两次滑动的结果不一致，请重新设置";
                      }
                  }
  
              } else {
  
                  // 解锁
  
                  if ([result isEqualToString:[df objectForKey:@"touchLock"] ]) {
                      self.touchLockView.alertLabel.text = @"解锁成功";
                  } else {
                      self.touchLockView.alertLabel.text = @"密码不正确，请重试";
                  }
              }
  
          } else {
  
              // 滑动点数过少
              self.touchLockView.alertLabel.text = result;
          }
      }

• 效果