在iOS上增加手势锁屏、解锁功能

在一些涉及个人隐私的场景下，尤其是当移动设备包含太多私密信息时，为用户的安全考虑是有必要的。

桌面版的QQ在很多年前就考虑到用户离开电脑后隐私泄露的危险，提供了“离开电脑自动锁定”或者“闲置锁定”等类似功能，具体我也忘了。

而在iPhone版的QQ上，也提供了手势锁的功能。如下图：

我在上一篇博文中简单提到如何根据手指移动画线条，而这里是进一步的版本，仍然只是粗糙原型：

具体的代码实现如下：

[cpp]
//
// ViewController.m
// GestureLock
//
// Created by Jason Lee on 12-9-26.
// Copyright (c) 2012年 Jason Lee. All rights reserved.
//

#import "ViewController.h"

#define LOCK_POINT_TAG      1000

@interface ViewController ()

@property (nonatomic, strong) UIImageView *imageView;

@property (nonatomic, assign) CGPoint lineStartPoint;
@property (nonatomic, assign) CGPoint lineEndPoint;

@property (nonatomic, strong) NSMutableArray *buttonArray;
@property (nonatomic, strong) NSMutableArray *selectedButtons;

@property (nonatomic, assign) BOOL drawFlag;

@property (nonatomic, strong) UIImage *pointImage;
@property (nonatomic, strong) UIImage *selectedImage;

@end

@implementation ViewController

- (void)dealloc
{
    [super dealloc];
    //
    [_imageView release];
    [_buttonArray release];
    [_selectedButtons release];
    [_pointImage release];
    [_selectedImage release];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    _imageView = [[UIImageView alloc] initWithFrame:self.view.bounds];
    [self.view addSubview:self.imageView];
    self.imageView.backgroundColor = [UIColor whiteColor];

    [self createLockPoints];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

#pragma mark - Trace Touch Point

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    if (touch) {
        for (UIButton *btn in self.buttonArray) {
            CGPoint 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];
                [btn setImage:self.selectedImage forState:UIControlStateNormal];
            }
        }
    }
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    if (touch && self.drawFlag) {
        self.lineEndPoint = [touch locationInView:self.imageView];

        for (UIButton *btn in self.buttonArray) {
            CGPoint touchPoint = [touch locationInView:btn];

            if ([btn pointInside:touchPoint withEvent:nil]) {
                BOOL btnContained = NO;

                for (UIButton *selectedBtn in self.selectedButtons) {
                    if (btn == selectedBtn) {
                        btnContained = YES;
                        break;
                    }
                }

                if (!btnContained) {
                    [self.selectedButtons addObject:btn];
                    [btn setImage:self.selectedImage forState:UIControlStateNormal];
                }
            }
        }

        self.imageView.image = [self drawUnlockLine]; <

补充：移动开发 , IOS ,