Objective-C 手势解锁App

IOS 手势锁屏实现逻辑分析：

    1、通过循环在页面中添加透明背景白色边框的按钮(默认为九个)并设置 tag 值，以便与原始密码核对

    2、扑捉手势，主要用到touchesBegan、touchesMoved 和 touchesEnded

    3、将手势经过的按钮划线链接起来，主要用到  CGContextRef 2D绘画对象

如下代码所示为 IOS 手势锁屏全部 App源码，仅供学习：

ViewController.h

#import <UIKit/UIKit.h>@interface ViewController : UIViewController//图片控件(画板)@property (weak, nonatomic) IBOutlet UIImageView *imgView;//起止点@property (nonatomic,assign) CGPoint lineStartPoint;@property (nonatomic,assign) CGPoint lineEndPoint;//所有按钮和选中的按钮@property (nonatomic,strong) NSMutableArray *buttonArray;@property (nonatomic,strong) NSMutableArray *selectedButtons;@property (nonatomic,assign) BOOL drawFlag;@end

ViewController.m

#import "ViewController.h"@implementation ViewController#pragma mark- Class property@synthesize drawFlag,imgView;@synthesize lineStartPoint,lineEndPoint;@synthesize buttonArray,selectedButtons;#pragma mark-Global variablesNSArray *arrImgs = nil;#pragma mark- Class method/** *  视图加载 */- (void)viewDidLoad {    [super viewDidLoad];    //设置定位    self.imgView.frame = self.view.frame;    //背景图片数组    arrImgs = [NSArray arrayWithObjects:@"bg_01.jpg",@"bg_02.jpg",@"bg_03.jpeg",               @"bg_04.png",@"bg_05.jpg",@"bg_06.jpeg",@"bg_07.jpeg", nil];    //加载按钮    [self loadButtons];    //随机设置背景图片    [self ChangeBgImg];}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}/** *  shouldAutorotate *  是否允许内容跟着屏幕切换而改变 * *  @return Bool */-(BOOL) shouldAutorotate{    return NO;}/** *  加载按钮 */-(void) loadButtons{    float w = 70;    float h = 70;    float x = 15;    float y = 150;    int space = 40;    self.buttonArray = [[NSMutableArray alloc] init];    for (int i = 0; i < 9; i++) {        if ((i % 3 == 0) && i > 0) {            //另起一行            y += h + space;            x = 15;        }        //添加按钮        [self CreateButton:(i+1) x: x y:y h:h w:w];        x += w + space;    }}/** *  touchesBegan 触摸开始事件 * *  @param touches touches description *  @param event   event description */-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    UITouch *touch = [touches anyObject];    if (touch) {        CGPoint touchPoint;        for (UIButton *btn in self.buttonArray) {            touchPoint = [touch locationInView:btn];            if ([btn pointInside:touchPoint withEvent:nil]) {                self.lineStartPoint = btn.center;                self.drawFlag = YES;                if (!self.selectedButtons)                    self.selectedButtons = [NSMutableArray arrayWithCapacity:9];                [self.selectedButtons addObject:btn];            }        }    }}/** *  touchesMoved 一根或者多根手指在屏幕上移动 * *  @param touches touches description *  @param event   event description */-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{    UITouch *touch =[touches anyObject];    if (touch && self.drawFlag) {        self.lineEndPoint = [touch locationInView:imgView];        CGPoint touchPoint;        BOOL btnContained;        for (UIButton *btn in self.buttonArray) {            touchPoint = [touch locationInView:btn];            if ([btn pointInside:touchPoint withEvent:nil]) {                btnContained = NO;                                //如要实现比较复杂手势，可考虑注释如下循环                for (UIButton *selectedBtn in self.selectedButtons) {                    if (btn == selectedBtn) {                        btnContained = YES;                        break;                    }                }                if (!btnContained)                    [self.selectedButtons addObject:btn];            }        }        //划线        UIColor *color = [UIColor whiteColor];        [self drawLineWithColor:color width:8.0f];    }}/** *  touchesEnded 滑动手势结束 * *  @param touches touches description *  @param event   event description */-(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{    self.drawFlag = NO;    self.selectedButtons = nil;    //判断手势密码是否正确,……}/** *  drawLineWithColor  *  自定义划线功能 * *  @param color      颜色 *  @param width      宽度 *  @param startPoint 开始位置 *  @param endPoint   结束位置 * *  @return UIImage */-(void) drawLineWithColor:(UIColor *)color width:(CGFloat)width{    CGPoint btnCenter;    UIImage *image = nil;    UIGraphicsBeginImageContext(self.imgView.frame.size);    //一个不透明类型的Quartz 2D绘画环境,相当于一个画布,你可以在上面任意绘画    CGContextRef context = UIGraphicsGetCurrentContext();    //设置划线宽度和颜色    CGContextSetLineWidth(context, width);    CGContextSetStrokeColorWithColor(context, [color CGColor]);    /**     * CGLineCap     *  kCGLineCapButt   //和第三个一样     *  kCGLineCapRound  //端点是圆的     *  kCGLineCapSquare //正方形     */    //设置线的端点形状    CGContextSetLineCap(context, kCGLineCapRound);    //设置线的起始位置    CGContextMoveToPoint(context, self.lineStartPoint.x, self.lineStartPoint.y);    //将选中的点连接起来    for (UIButton *selectBtn in self.selectedButtons) {        btnCenter = selectBtn.center;        CGContextAddLineToPoint(context, btnCenter.x, btnCenter.y);        CGContextMoveToPoint(context, btnCenter.x, btnCenter.y);    }    //结束位置    CGContextAddLineToPoint(context, self.lineEndPoint.x, self.lineEndPoint.y);    CGContextStrokePath(context);    image = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    //追加到画板    self.imgView.image = image;    image = nil;}/** *  CButton 自定义按钮 * *  @param int   按钮的值 *  @param float x *  @param float y *  @param float width *  @param float height * *  @return void */-(void) CreateButton:(int) v x:(float) x y:(float) y h:(float) h w:(float) w{    //初始化按钮    UIButton *cbtn = [[UIButton alloc] init];    //设置位置和尺寸    cbtn.frame = CGRectMake(x, y, w, h);    //设置按钮信息    cbtn.userInteractionEnabled = NO;    cbtn.tag = v;    //设置字体颜色    [cbtn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];    //设置背景颜色    [cbtn setBackgroundColor:[UIColor clearColor]];    //设置为圆形    cbtn.layer.cornerRadius = 35;    cbtn.layer.borderWidth = 3.5;    cbtn.layer.borderColor = [UIColor whiteColor].CGColor;    cbtn.clipsToBounds = TRUE;//去除边界    //添加到当前视图    [self.view addSubview:cbtn];    //添加到数组    [self.buttonArray addObject:cbtn];    //释放    cbtn = nil;};/** *  ChangeBgImg *  随机设置背景图片 */-(void) ChangeBgImg{    //获取背景图片控件    UIImageView *bgImgV = (UIImageView*)[self.view viewWithTag:11];    if (bgImgV) {        bgImgV.frame = self.view.frame;        //获取随机索引        int rd = 0 + (arc4random() % ([arrImgs count] - 1));        NSString *strImgName = (NSString*)[arrImgs objectAtIndex:rd];        bgImgV.image = [UIImage imageNamed:strImgName];    }}@end

源码下载地址：

http://pan.baidu.com/s/1bnhLWIF

在本项目制作过程中，如下文章给予了相当大的帮助，以示感谢：
http://blog.csdn.net/jasonblog/article/details/8024014

http://blog.csdn.net/jasonblog/article/details/8024674

http://blog.sina.com.cn/s/blog_7a162d000101dag2.html

如下为效果图：