ScreenUnLock 与智能手机上的图案解锁功能一样。通过绘制图形达到解锁或记忆图形的目的。
本人突发奇想，把手机上的图形解锁功能移植到WPF中。也应用到了公司的项目中。
在创建ScreenUnLock之前，先来分析一下图形解锁的实现思路。
1.创建九宫格原点(或更多格子)，每个点定义一个坐标值
2.提供图形解锁相关扩展属性和事件，方便调用者定义。比如：点和线的颜色(Color)，操作模式(Check|Remember)，验证正确的颜色(RightColor), 验证失败的颜色(ErrorColor), 解锁事件 OnCheckedPoint，记忆事件 OnRememberPoint 等;
3.定义MouseMove事件监听画线行为。 画线部分也是本文的核心。在画线过程中。程序需判断，线条从哪个点开始绘制，经过了哪个点(排除已经记录的点)。是否完成了绘制等等。
4.画线完成，根据操作模式处理画线完成行为。并调用相关自定义事件
大致思路如上，下面开始一步一步编写ScreenUnLock吧
创建ScreenUnLock
public partial class ScreenUnlock : UserControl
定义相关属性
1 /// <summary> 2 /// 验证正确的颜色 3 /// </summary> 4 private SolidColorBrush rightColor; 5 6 /// <summary> 7 /// 验证失败的颜色 8 /// </summary> 9 private SolidColorBrush errorColor; 10 11 /// <summary> 12 /// 图案是否在检查中 13 /// </summary> 14 private bool isChecking; 15 16 public static readonly DependencyProperty PointArrayProperty = DependencyProperty.Register("PointArray", typeof(IList<string>), typeof(ScreenUnlock)); 17 /// <summary> 18 /// 记忆的坐标点 19 /// </summary> 20 public IList<string> PointArray 21 { 22 get { return GetValue(PointArrayProperty) as IList<string>; } 23 set { SetValue(PointArrayProperty, value); } 24 } 25 26 /// <summary> 27 /// 当前坐标点集合 28 /// </summary> 29 private IList<string> currentPointArray; 30 31 /// <summary> 32 /// 当前线集合 33 /// </summary> 34 private IList<Line> currentLineList; 35 36 /// <summary> 37 /// 点集合 38 /// </summary> 39 private IList<Ellipse> ellipseList; 40 41 /// <summary> 42 /// 当前正在绘制的线 43 /// </summary> 44 private Line currentLine; 45 46 public static readonly DependencyProperty OperationPorperty = DependencyProperty.Register("Operation", typeof(ScreenUnLockOperationType), typeof(ScreenUnlock), new FrameworkPropertyMetadata(ScreenUnLockOperationType.Remember)); 47 /// <summary> 48 /// 操作类型 49 /// </summary> 50 public ScreenUnLockOperationType Operation 51 { 52 get { return (ScreenUnLockOperationType)GetValue(OperationPorperty); } 53 set { SetValue(OperationPorperty, value); } 54 } 55 56 public static readonly DependencyProperty PointSizeProperty = DependencyProperty.Register("PointSize", typeof(double), typeof(ScreenUnlock), new FrameworkPropertyMetadata(15.0)); 57 /// <summary> 58 /// 坐标点大小 59 /// </summary> 60 public double PointSize 61 { 62 get { return Convert.ToDouble(GetValue(PointSizeProperty)); } 63 set { SetValue(PointSizeProperty, value); } 64 } 65 66 67 public static readonly DependencyProperty ColorProperty = DependencyProperty.Register("Color", typeof(SolidColorBrush), typeof(ScreenUnlock), new FrameworkPropertyMetadata(new SolidColorBrush(Colors.White), new PropertyChangedCallback((s, e) => 68 { 69 (s as ScreenUnlock).Refresh(); 70 }))); 71 72 /// <summary> 73 /// 坐标点及线条颜色 74 /// </summary> 75 public SolidColorBrush Color 76 { 77 get { return GetValue(ColorProperty) as SolidColorBrush; } 78 set { SetValue(ColorProperty, value); } 79 }
/// <summary>
/// 操作类型
/// </summary>
public enum ScreenUnLockOperationType
{
Remember = 0, Check = 1
}
初始化ScreenUnLock
public ScreenUnlock() { InitializeComponent(); this.Loaded += ScreenUnlock_Loaded; this.Unloaded += ScreenUnlock_Unloaded; this.MouseMove += ScreenUnlock_MouseMove; //监听绘制事件 } private void ScreenUnlock_Loaded(object sender, RoutedEventArgs e) { isChecking = false; rightColor = new SolidColorBrush(Colors.Green); errorColor = new SolidColorBrush(Colors.Red); currentPointArray = new List<string>(); currentLineList = new List<Line>(); ellipseList = new List<Ellipse>(); CreatePoint(); } private void ScreenUnlock_Unloaded(object sender, RoutedEventArgs e) { rightColor = null; errorColor = null; if (currentPointArray != null) this.currentPointArray.Clear(); if (currentLineList != null) this.currentLineList.Clear(); if (ellipseList != null) ellipseList.Clear(); this.canvasRoot.Children.Clear(); }
创建点
1 /// <summary> 2 /// 创建点 3 /// </summary> 4 private void CreatePoint() 5 { 6 canvasRoot.Children.Clear(); 7 int row = 3, column = 3; //三行三列，九宫格 8 double oneColumnWidth = (this.ActualWidth == 0 ? this.Width : this.ActualWidth) / 3; //单列的宽度 9 double oneRowHeight = (this.ActualHeight == 0 ? this.Height : this.ActualHeight) / 3; //单列的高度 10 double leftDistance = (oneColumnWidth - PointSize) / 2; //单列左边距 11 double topDistance = (oneRowHeight - PointSize) / 2; //单列上边距 12 for (var i = 0; i < row; i++) 13 { 14 for (var j = 0; j < column; j++) 15 { 16 Ellipse ellipse = new Ellipse() 17 { 18 Width = PointSize, 19 Height = PointSize, 20 Fill = Color, 21 Tag = string.Format("{0}{1}", i, j) 22 }; 23 Canvas.SetLeft(ellipse, j * oneColumnWidth + leftDistance); 24 Canvas.SetTop(ellipse, i * oneRowHeight + topDistance); 25 canvasRoot.Children.Add(ellipse); 26 ellipseList.Add(ellipse); 27 } 28 } 29 }
创建线
1 private Line CreateLine() 2 { 3 Line line = new Line() 4 { 5 Stroke = Color, 6 StrokeThickness = 2 7 }; 8 return line; 9 }
点和线都创建都定义好了，可以开始监听绘制事件了
1 private void ScreenUnlock_MouseMove(object sender, System.Windows.Input.MouseEventArgs e) 2 { 3 if (isChecking) //如果图形正在检查中，不响应后续处理 4 return; 5 if (e.LeftButton == System.Windows.Input.MouseButtonState.Pressed) 6 { 7 var point = e.GetPosition(this); 8 HitTestResult result = VisualTreeHelper.HitTest(this, point); 9 Ellipse ellipse = result.VisualHit as Ellipse; 10 if (ellipse != null) 11 { 12 if (currentLine == null) 13 { 14 //从头开始绘制 15 currentLine = CreateLine(); 16 var ellipseCenterPoint = GetCenterPoint(ellipse); 17 currentLine.X1 = currentLine.X2 = ellipseCenterPoint.X; 18 currentLine.Y1 = currentLine.Y2 = ellipseCenterPoint.Y; 19 20 currentPointArray.Add(ellipse.Tag.ToString()); 21 Console.WriteLine(string.Join(",", currentPointArray)); 22 currentLineList.Add(currentLine); 23 canvasRoot.Children.Add(currentLine); 24 } 25 else 26 { 27 //遇到下一个点，排除已经经过的点 28 if (currentPointArray.Contains(ellipse.Tag.ToString())) 29 return; 30 OnAfterByPoint(ellipse); 31 } 32 } 33 else if (currentLine != null) 34 { 35 //绘制过程中 36 currentLine.X2 = point.X; 37 currentLine.Y2 = point.Y; 38 39 //判断当前Line是否经过点 40 ellipse = IsOnLine(); 41 if (ellipse != null) 42 OnAfterByPoint(ellipse); 43 } 44 } 45 else 46 { 47 if (currentPointArray.Count == 0) 48 return; 49 isChecking = true; 50 if (currentLineList.Count + 1 != currentPointArray.Count) 51 { 52 //最后一条线的终点不在点上 53 //两点一线，点的个数-1等于线的条数 54 currentLineList.Remove(currentLine); //从已记录的线集合中删除最后一条多余的线 55 canvasRoot.Children.Remove(currentLine); //从界面上删除最后一条多余的线 56 currentLine = null; 57 } 58 59 if (Operation == ScreenUnLockOperationType.Check) 60 { 61 Console.WriteLine("playAnimation Check"); 62 var result = CheckPoint(); //执行图形检查
//执行完成动画并触发检查事件 63 PlayAnimation(result, () => 64 { 65 if (OnCheckedPoint != null) 66 { 67 this.Dispatcher.BeginInvoke(OnCheckedPoint, this, new CheckPointArgs() { Result = result }); //触发检查完成事件 68 } 69 }); 70 71 } 72 else if (Operation == ScreenUnLockOperationType.Remember) 73 { 74 Console.WriteLine("playAnimation Remember"); 75 RememberPoint(); //记忆绘制的坐标 76 var args = new RememberPointArgs() { PointArray = this.PointArray };
//执行完成动画并触发记忆事件 77 PlayAnimation(true, () => 78 { 79 if (OnRememberPoint != null) 80 { 81 this.Dispatcher.BeginInvoke(OnRememberPoint, this, args); //触发图形记忆事件 82 } 83 }); 84 } 85 } 86 }
判断线是否经过了附近的某个点
1 /// <summary> 2 /// 两点计算一线的长度 3 /// </summary> 4 /// <param name="pt1"></param> 5 /// <param name="pt2"></param> 6 /// <returns></returns> 7 private double GetLineLength(double x1, double y1, double x2, double y2) 8 { 9 return Math.Sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2)); //根据两点计算线段长度公式 √((x1-x2)²x(y1-y2)²) 10 } 11 12 /// <summary> 13 /// 判断线是否经过了某个点 14 /// </summary> 16 /// <param name="ellipse"></param> 17 /// <returns></returns> 18 private Ellipse IsOnLine() 19 { 20 double lineAB = 0; //当前画线的长度 21 double lineCA = 0; //当前点和A点的距离 22 double lineCB = 0; //当前点和B点的距离 23 double dis = 0; 24 double deciation = 1; //允许的偏差距离 25 lineAB = GetLineLength(currentLine.X1, currentLine.Y1, currentLine.X2, currentLine.Y2); //计算当前画线的长度 26 27 foreach (Ellipse ellipse in ellipseList) 28 { 29 if (currentPointArray.Contains(ellipse.Tag.ToString())) //排除已经经过的点 30 continue; 31 var ellipseCenterPoint = GetCenterPoint(ellipse); //取当前点的中心点 32 lineCA = GetLineLength(currentLine.X1, currentLine.Y1, ellipseCenterPoint.X, ellipseCenterPoint.Y); //计算当前点到线A端的长度 33 lineCB = GetLineLength(currentLine.X2, currentLine.Y2, ellipseCenterPoint.X, ellipseCenterPoint.Y); //计算当前点到线B端的长度 34 dis = Math.Abs(lineAB - (lineCA + lineCB)); //线CA的长度+线CB的长度>当前线AB的长度 说明点不在线上 35 if (dis <= deciation) //因为绘制的点具有一个宽度和高度，所以需设定一个允许的偏差范围，让线靠近点就命中之（吸附效果） 36 { 37 return ellipse; 38 } 39 } 40 return null; 41 }
检查点是否正确，按数组顺序逐个匹配之
1 /// <summary> 2 /// 检查坐标点是否正确 3 /// </summary> 4 /// <returns></returns> 5 private bool CheckPoint() 6 {
//PointArray:正确的坐标值数组
//currentPointArray:当前绘制的坐标值数组 7 if (currentPointArray.Count != PointArray.Count) 8 return false; 9 for (var i = 0; i < currentPointArray.Count; i++) 10 { 11 if (currentPointArray[i] != PointArray[i]) 12 return false; 13 } 14 return true; 15 }
记录经过点，并创建一条新的线
1 /// <summary> 2 /// 记录经过的点 3 /// </summary> 4 /// <param name="ellipse"></param> 5 private void OnAfterByPoint(Ellipse ellipse) 6 { 7 var ellipseCenterPoint = GetCenterPoint(ellipse); 8 currentLine.X2 = ellipseCenterPoint.X; 9 currentLine.Y2 = ellipseCenterPoint.Y; 10 currentLine = CreateLine(); 11 currentLine.X1 = currentLine.X2 = ellipseCenterPoint.X; 12 currentLine.Y1 = currentLine.Y2 = ellipseCenterPoint.Y; 13 currentPointArray.Add(ellipse.Tag.ToString()); 14 Console.WriteLine(string.Join(",", currentPointArray)); 15 currentLineList.Add(currentLine); 16 canvasRoot.Children.Add(currentLine); 17 }
1 /// <summary> 2 /// 获取原点的中心点坐标 3 /// </summary> 4 /// <param name="ellipse"></param> 5 /// <returns></returns> 6 private Point GetCenterPoint(Ellipse ellipse) 7 { 8 Point p = new Point(Canvas.GetLeft(ellipse) + ellipse.Width / 2, Canvas.GetTop(ellipse) + ellipse.Height / 2); 9 return p; 10 } 11
当绘制完成时，执行完成动画并触发响应模式的事件
1 /// <summary> 2 /// 执行动画 3 /// </summary> 4 /// <param name="result"></param> 5 private void PlayAnimation(bool result, Action callback = null) 6 { 7 Task.Factory.StartNew(() => 8 { 9 this.Dispatcher.Invoke((Action)delegate 10 { 11 foreach (Line l in currentLineList) 12 l.Stroke = result ? rightColor : errorColor; 13 foreach (Ellipse e in ellipseList) 14 if (currentPointArray.Contains(e.Tag.ToString())) 15 e.Fill = result ? rightColor : errorColor; 16 }); 17 Thread.Sleep(1500); 18 this.Dispatcher.Invoke((Action)delegate 19 { 20 foreach (Line l in currentLineList) 21 this.canvasRoot.Children.Remove(l); 22 foreach (Ellipse e in ellipseList) 23 e.Fill = Color; 24 }); 25 currentLine = null; 26 this.currentPointArray.Clear(); 27 this.currentLineList.Clear(); 28 isChecking = false; 29 }).ContinueWith(t => 30 { 31 try 32 { 33 if (callback != null) 34 callback(); 35 } 36 catch (Exception ex) 37 { 38 Console.WriteLine(ex.Message); 39 } 40 finally 41 { 42 t.Dispose(); 43 } 44 }); 45 }
图形解锁的调用
1 <local:ScreenUnlock Width="500" Height="500" 2 PointArray="{Binding PointArray, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" 3 Operation="Check"> <!--或Remember--> 4 <i:Interaction.Triggers> 5 <i:EventTrigger EventName="OnCheckedPoint"> 6 <Custom:EventToCommand Command="{Binding OnCheckedPoint}" PassEventArgsToCommand="True"/> 7 </i:EventTrigger> 8 <i:EventTrigger EventName="OnRememberPoint"> 9 <Custom:EventToCommand Command="{Binding OnRememberPoint}" PassEventArgsToCommand="True"/> 10 </i:EventTrigger> 11 </i:Interaction.Triggers> 12 </local:ScreenUnlock>
