WPF图形解锁控件ScreenUnLock使用详解
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
///
/// 验证正确的颜色
///
private SolidColorBrush rightColor;
///
/// 验证失败的颜色
///
private SolidColorBrush errorColor;
///
/// 图案是否在检查中
///
private bool isChecking;
public static readonly DependencyProperty PointArrayProperty = DependencyProperty.Register("PointArray", typeof(IList), typeof(ScreenUnlock));
///
/// 记忆的坐标点
///
public IList PointArray
{
get { return GetValue(PointArrayProperty) as IList; }
set { SetValue(PointArrayProperty, value); }
}
///
/// 当前坐标点集合
///
private IList currentPointArray;
///
/// 当前线集合
///
private IList currentLineList;
///
/// 点集合
///
private IList ellipseList;
///
/// 当前正在绘制的线
///
private Line currentLine;
public static readonly DependencyProperty OperationPorperty = DependencyProperty.Register("Operation", typeof(ScreenUnLockOperationType), typeof(ScreenUnlock), new FrameworkPropertyMetadata(ScreenUnLockOperationType.Remember));
///
/// 操作类型
///
public ScreenUnLockOperationType Operation
{
get { return (ScreenUnLockOperationType)GetValue(OperationPorperty); }
set { SetValue(OperationPorperty, value); }
}
public static readonly DependencyProperty PointSizeProperty = DependencyProperty.Register("PointSize", typeof(double), typeof(ScreenUnlock), new FrameworkPropertyMetadata(15.0));
///
/// 坐标点大小
///
public double PointSize
{
get { return Convert.ToDouble(GetValue(PointSizeProperty)); }
set { SetValue(PointSizeProperty, value); }
}
public static readonly DependencyProperty ColorProperty = DependencyProperty.Register("Color", typeof(SolidColorBrush), typeof(ScreenUnlock), new FrameworkPropertyMetadata(new SolidColorBrush(Colors.White), new PropertyChangedCallback((s, e) =>
{
(s as ScreenUnlock).Refresh();
})));
///
/// 坐标点及线条颜色
///
public SolidColorBrush Color
{
get { return GetValue(ColorProperty) as SolidColorBrush; }
set { SetValue(ColorProperty, value); }
}
///
/// 操作类型
///
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();
currentLineList = new List();
ellipseList = new List();
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
///
/// 创建点
///
private void CreatePoint()
{
canvasRoot.Children.Clear();
int row = 3, column = 3; //三行三列，九宫格
double oneColumnWidth = (this.ActualWidth == 0 ? this.Width : this.ActualWidth) / 3; //单列的宽度
double oneRowHeight = (this.ActualHeight == 0 ? this.Height : this.ActualHeight) / 3; //单列的高度
double leftDistance = (oneColumnWidth - PointSize) / 2; //单列左边距
double topDistance = (oneRowHeight - PointSize) / 2; //单列上边距
for (var i = 0; i < row; i++)
{
for (var j = 0; j < column; j++)
{
Ellipse ellipse = new Ellipse()
{
Width = PointSize,
Height = PointSize,
Fill = Color,
Tag = string.Format("{0}{1}", i, j)
};
Canvas.SetLeft(ellipse, j * oneColumnWidth + leftDistance);
Canvas.SetTop(ellipse, i * oneRowHeight + topDistance);
canvasRoot.Children.Add(ellipse);
ellipseList.Add(ellipse);
}
}
}
创建线
private Line CreateLine()
{
Line line = new Line()
{
Stroke = Color,
StrokeThickness = 2
};
return line;
}
点和线都创建都定义好了，可以开始监听绘制事件了
private void ScreenUnlock_MouseMove(object sender, System.Windows.Input.MouseEventArgs e)
{
if (isChecking) //如果图形正在检查中，不响应后续处理
return;
if (e.LeftButton == System.Windows.Input.MouseButtonState.Pressed)
{
var point = e.GetPosition(this);
HitTestResult result = VisualTreeHelper.HitTest(this, point);
Ellipse ellipse = result.VisualHit as Ellipse;
if (ellipse != null)
{
if (currentLine == null)
{
//从头开始绘制
currentLine = CreateLine();
var ellipseCenterPoint = GetCenterPoint(ellipse);
currentLine.X1 = currentLine.X2 = ellipseCenterPoint.X;
currentLine.Y1 = currentLine.Y2 = ellipseCenterPoint.Y;
currentPointArray.Add(ellipse.Tag.ToString());
Console.WriteLine(string.Join(",", currentPointArray));
currentLineList.Add(currentLine);
canvasRoot.Children.Add(currentLine);
}
else
{
//遇到下一个点，排除已经经过的点
if (currentPointArray.Contains(ellipse.Tag.ToString()))
return;
OnAfterByPoint(ellipse);
}
}
else if (currentLine != null)
{
//绘制过程中
currentLine.X2 = point.X;
currentLine.Y2 = point.Y;
//判断当前Line是否经过点
ellipse = IsOnLine();
if (ellipse != null)
OnAfterByPoint(ellipse);
}
}
else
{
if (currentPointArray.Count == 0)
return;
isChecking = true;
if (currentLineList.Count + 1 != currentPointArray.Count)
{
//最后一条线的终点不在点上
//两点一线，点的个数-1等于线的条数
currentLineList.Remove(currentLine); //从已记录的线集合中删除最后一条多余的线
canvasRoot.Children.Remove(currentLine); //从界面上删除最后一条多余的线
currentLine = null;
}
if (Operation == ScreenUnLockOperationType.Check)
{
Console.WriteLine("playAnimation Check");
var result = CheckPoint(); //执行图形检查
//执行完成动画并触发检查事件
PlayAnimation(result, () =>
{
if (OnCheckedPoint != null)
{
this.Dispatcher.BeginInvoke(OnCheckedPoint, this, new CheckPointArgs() { Result = result }); //触发检查完成事件
}
});
}
else if (Operation == ScreenUnLockOperationType.Remember)
{
Console.WriteLine("playAnimation Remember");
RememberPoint(); //记忆绘制的坐标
var args = new RememberPointArgs() { PointArray = this.PointArray };
//执行完成动画并触发记忆事件
PlayAnimation(true, () =>
{
if (OnRememberPoint != null)
{
this.Dispatcher.BeginInvoke(OnRememberPoint, this, args); //触发图形记忆事件
}
});
}
}
}
判断线是否经过了附近的某个点
///
/// 两点计算一线的长度
///
///
///
///
private double GetLineLength(double x1, double y1, double x2, double y2)
{
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)
}
///
/// 判断线是否经过了某个点
///
///
///
private Ellipse IsOnLine()
{
double lineAB = 0; //当前画线的长度
double lineCA = 0; //当前点和A点的距离
double lineCB = 0; //当前点和B点的距离
double dis = 0;
double deciation = 1; //允许的偏差距离
lineAB = GetLineLength(currentLine.X1, currentLine.Y1, currentLine.X2, currentLine.Y2); //计算当前画线的长度
foreach (Ellipse ellipse in ellipseList)
{
if (currentPointArray.Contains(ellipse.Tag.ToString())) //排除已经经过的点
continue;
var ellipseCenterPoint = GetCenterPoint(ellipse); //取当前点的中心点
lineCA = GetLineLength(currentLine.X1, currentLine.Y1, ellipseCenterPoint.X, ellipseCenterPoint.Y); //计算当前点到线A端的长度
lineCB = GetLineLength(currentLine.X2, currentLine.Y2, ellipseCenterPoint.X, ellipseCenterPoint.Y); //计算当前点到线B端的长度
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
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）
{
return ellipse;
}
}
return null;
}
检查点是否正确，按数组顺序逐个匹配之
///
/// 检查坐标点是否正确
///
///
private bool CheckPoint()
{
//PointArray:正确的坐标值数组
//currentPointArray:当前绘制的坐标值数组
if (currentPointArray.Count != PointArray.Count)
return false;
for (var i = 0; i < currentPointArray.Count; i++)
{
if (currentPointArray[i] != PointArray[i])
return false;
}
return true;
}
记录经过点，并创建一条新的线
///
/// 记录经过的点
///
///
private void OnAfterByPoint(Ellipse ellipse)
{
var ellipseCenterPoint = GetCenterPoint(ellipse);
currentLine.X2 = ellipseCenterPoint.X;
currentLine.Y2 = ellipseCenterPoint.Y;
currentLine = CreateLine();
currentLine.X1 = currentLine.X2 = ellipseCenterPoint.X;
currentLine.Y1 = currentLine.Y2 = ellipseCenterPoint.Y;
currentPointArray.Add(ellipse.Tag.ToString());
Console.WriteLine(string.Join(",", currentPointArray));
currentLineList.Add(currentLine);
canvasRoot.Children.Add(currentLine);
}
///
/// 获取原点的中心点坐标
///
///
///
private Point GetCenterPoint(Ellipse ellipse)
{
Point p = new Point(Canvas.GetLeft(ellipse) + ellipse.Width / 2, Canvas.GetTop(ellipse) + ellipse.Height / 2);
return p;
}
当绘制完成时，执行完成动画并触发响应模式的事件
///
/// 执行动画
///
///
private void PlayAnimation(bool result, Action callback = null)
{
Task.Factory.StartNew(() =>
{
this.Dispatcher.Invoke((Action)delegate
{
foreach (Line l in currentLineList)
l.Stroke = result ? rightColor : errorColor;
foreach (Ellipse e in ellipseList)
if (currentPointArray.Contains(e.Tag.ToString()))
e.Fill = result ? rightColor : errorColor;
});
Thread.Sleep(1500);
this.Dispatcher.Invoke((Action)delegate
{
foreach (Line l in currentLineList)
this.canvasRoot.Children.Remove(l);
foreach (Ellipse e in ellipseList)
e.Fill = Color;
});
currentLine = null;
this.currentPointArray.Clear();
this.currentLineList.Clear();
isChecking = false;
}).ContinueWith(t =>
{
try
{
if (callback != null)
callback();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
t.Dispose();
}
});
}
图形解锁的调用
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持中文源码网。