我有以下代码：
private Point initialpoint;
private void ManipulationStarted(object sender, ManipulationStartedRoutedEventArgs e)
{
initialpoint = e.Position;
}
private void ManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e)
{
Point currentpoint = e.Position;
if (currentpoint.X - initialpoint.X >= 100)
{
System.Diagnostics.Debug.WriteLine("Swipe Right");
e.Complete();
}
}
我可以很容易地处理 1 个手指滑动手势，但我也想处理 2、3、4 个手指滑动手势。谁能告诉我该怎么做？
根据this MSDN Forum Posting，您将需要使用指针通知。包含工作示例代码的文档位于MSDN 库中
从最后一个链接：
指针对象表示来自输入设备（例如鼠标、笔/触笔、单指或多指）的单个唯一输入“接触”（PointerPoint）。系统在首次检测到接触时创建一个指针，并在指针离开（离开）检测范围或取消时销毁它。在多个设备或多点触控输入的情况下，每个接触都被视为唯一的指针。
请注意，我没有多点触控 Windows 8 设备来测试此代码。因此，它已经在 Simuator 中进行了所有限制的测试，并且如上述链接中所述，Windows 8 没有内置手势支持来检测多个手指，您必须使用较低级别的功能。
首先，我在上面的 MSDN 示例代码中添加了两个字典，并为您的 Swipe Threshold 添加了两个变量到类定义中。
Dictionary<uint, Point> startLocation;
Dictionary<uint, bool> pointSwiped;
int swipeThresholdX = 100;
int swipeThresholdY = 100;
然后我在表单的构造函数中初始化字典
startLocation = new Dictionary<uint, Point>((int)SupportedContacts.Contacts);
pointSwiped = new Dictionary<uint, bool>((int)SupportedContacts.Contacts);
然后，原始词典添加到或删除项目的每个地方我都对新词典的
添加：
startLocation[pt.PointerId] = pt.Position;
pointSwiped[pt.PointerId] = false;
删除：
startLocation.Remove(pt.PointerId);
pointSwiped.Remove(pt.PointerId);
然后最后把它们放在PointerMovedEvent中：
private void targetContainer_PointerMoved(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint currentPoint = e.GetCurrentPoint(targetContainer);
if (currentPoint.IsInContact)
{
if (startLocation.ContainsKey(currentPoint.PointerId))
{
Point startPoint = startLocation[currentPoint.PointerId];
if (Math.Abs(currentPoint.Position.X - startPoint.X) > swipeThresholdX) // I only did one Axis for testing
{
pointSwiped[currentPoint.PointerId] = true;
}
}
}
updateInfoPop(e);
}
最终修改的 MSDN 示例：
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
// The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234238
namespace PointerInput
{
/// <summary>
/// An empty page that can be used on its own or navigated to within a Frame.
/// </summary>
public sealed partial class MainPage : Page
{
Windows.Devices.Input.TouchCapabilities SupportedContacts = new Windows.Devices.Input.TouchCapabilities();
uint numActiveContacts;
Dictionary<uint, Windows.UI.Input.PointerPoint> contacts;
Dictionary<uint, Point> startLocation;
Dictionary<uint, bool> pointSwiped;
int swipeThresholdX = 100;
int swipeThresholdY = 100;
public MainPage()
{
this.InitializeComponent();
numActiveContacts = 0;
contacts = new Dictionary<uint, Windows.UI.Input.PointerPoint>((int)SupportedContacts.Contacts);
startLocation = new Dictionary<uint, Point>((int)SupportedContacts.Contacts);
pointSwiped = new Dictionary<uint, bool>((int)SupportedContacts.Contacts);
targetContainer.PointerPressed += new PointerEventHandler(targetContainer_PointerPressed);
targetContainer.PointerEntered += new PointerEventHandler(targetContainer_PointerEntered);
targetContainer.PointerReleased += new PointerEventHandler(targetContainer_PointerReleased);
targetContainer.PointerExited += new PointerEventHandler(targetContainer_PointerExited);
targetContainer.PointerCanceled += new PointerEventHandler(targetContainer_PointerCanceled);
targetContainer.PointerCaptureLost += new PointerEventHandler(targetContainer_PointerCaptureLost);
targetContainer.PointerMoved += new PointerEventHandler(targetContainer_PointerMoved);
}
// PointerPressed and PointerReleased events do not always occur in pairs.
// Your app should listen for and handle any event that might conclude a pointer down action
// (such as PointerExited, PointerCanceled, and PointerCaptureLost).
void targetContainer_PointerPressed(object sender, PointerRoutedEventArgs e)
{
if (Convert.ToBoolean(SupportedContacts.TouchPresent) && (numActiveContacts > SupportedContacts.Contacts))
{
// cannot support more contacts
eventLog.Text += "\nNumber of contacts exceeds the number supported by the device.";
return;
}
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(targetContainer);
// Update event sequence.
eventLog.Text += "\nDown: " + pt.PointerId;
// Change background color of target when pointer contact detected.
targetContainer.Fill = new SolidColorBrush(Windows.UI.Colors.Green);
// Check if pointer already exists (if enter occurred prior to down).
if (contacts.ContainsKey(pt.PointerId))
{
return;
}
contacts[pt.PointerId] = pt;
startLocation[pt.PointerId] = pt.Position;
pointSwiped[pt.PointerId] = false;
++numActiveContacts;
e.Handled = true;
// Display pointer details.
createInfoPop(e);
}
private void targetContainer_PointerEntered(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(targetContainer);
// Update event sequence.
eventLog.Text += "\nOver: " + pt.PointerId;
if (contacts.Count == 0)
{
// Change background color of target when pointer contact detected.
targetContainer.Fill = new SolidColorBrush(Windows.UI.Colors.Blue);
}
// Check if pointer already exists (if enter occurred prior to down).
if (contacts.ContainsKey(pt.PointerId))
{
return;
}
// Push new pointer Id onto expando target pointers array.
contacts[pt.PointerId] = pt;
startLocation[pt.PointerId] = pt.Position;
pointSwiped[pt.PointerId] = false;
++numActiveContacts;
e.Handled = true;
// Display pointer details.
createInfoPop(e);
}
// Fires for for various reasons, including:
// - User interactions
// - Programmatic caputre of another pointer
// - Captured pointer was deliberately released
// PointerCaptureLost can fire instead of PointerReleased.
private void targetContainer_PointerCaptureLost(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(targetContainer);
// Update event sequence.
eventLog.Text += "\nPointer capture lost: " + pt.PointerId;
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
// Update the UI and pointer details.
foreach (TextBlock tb in pointerInfo.Children)
{
if (tb.Name == e.Pointer.PointerId.ToString())
{
pointerInfo.Children.Remove(tb);
}
}
if (contacts.Count == 0)
{
targetContainer.Fill = new SolidColorBrush(Windows.UI.Colors.Black);
}
e.Handled = true;
}
// Fires for for various reasons, including:
// - A touch contact is canceled by a pen coming into range of the surface.
// - The device doesn't report an active contact for more than 100ms.
// - The desktop is locked or the user logged off.
// - The number of simultaneous contacts exceeded the number supported by the device.
private void targetContainer_PointerCanceled(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(targetContainer);
// Update event sequence.
eventLog.Text += "\nPointer canceled: " + pt.PointerId;
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
// Update the UI and pointer details.
foreach (TextBlock tb in pointerInfo.Children)
{
if (tb.Name == e.Pointer.PointerId.ToString())
{
pointerInfo.Children.Remove(tb);
}
}
if (contacts.Count == 0)
{
targetContainer.Fill = new SolidColorBrush(Windows.UI.Colors.Black);
}
e.Handled = true;
}
private void targetContainer_PointerExited(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(targetContainer);
// Update event sequence.
eventLog.Text += "\nPointer exited: " + pt.PointerId;
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
// Update the UI and pointer details.
foreach (TextBlock tb in pointerInfo.Children)
{
if (tb.Name == e.Pointer.PointerId.ToString())
{
pointerInfo.Children.Remove(tb);
}
}
if (contacts.Count == 0)
{
targetContainer.Fill = new SolidColorBrush(Windows.UI.Colors.Gray);
}
e.Handled = true;
}
/// <summary>
/// Invoked when this page is about to be displayed in a Frame.
/// </summary>
/// <param name="e">Event data that describes how this page was reached. The Parameter
/// property is typically used to configure the page.</param>
protected override void OnNavigatedTo(NavigationEventArgs e)
{
}
void targetContainer_PointerReleased(object sender, PointerRoutedEventArgs e)
{
foreach (TextBlock tb in pointerInfo.Children)
{
if (tb.Name == e.Pointer.PointerId.ToString())
{
pointerInfo.Children.Remove(tb);
}
}
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(targetContainer);
// Update event sequence.
eventLog.Text += "\nUp: " + pt.PointerId;
// Change background color of target when pointer contact detected.
targetContainer.Fill = new SolidColorBrush(Windows.UI.Colors.Red);
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if(pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
e.Handled = true;
}
private void targetContainer_PointerMoved(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint currentPoint = e.GetCurrentPoint(targetContainer);
if (currentPoint.IsInContact)
{
if (startLocation.ContainsKey(currentPoint.PointerId))
{
Point startPoint = startLocation[currentPoint.PointerId];
if (Math.Abs(currentPoint.Position.X - startPoint.X) > swipeThresholdX) // I only did one Axis for testing
{
pointSwiped[currentPoint.PointerId] = true;
}
}
}
updateInfoPop(e);
}
int numberOfSwipedFingers()
{
int count = 0;
foreach (var item in pointSwiped)
{
if (item.Value) { count += 1; }
}
return count;
}
void checkSwipe()
{
int fingers = numberOfSwipedFingers();
if (fingers > 1)
{
eventLog.Text += "\nNumber of Swiped fingers = " + fingers;
}
else if (fingers == 1)
{
eventLog.Text += "\nNumber of Swiped fingers = " + fingers;
}
if(fingers > 0)
pointSwiped.Clear();
}
void createInfoPop(PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint currentPoint = e.GetCurrentPoint(targetContainer);
TextBlock pointerDetails = new TextBlock();
pointerDetails.Name = currentPoint.PointerId.ToString();
pointerDetails.Foreground = new SolidColorBrush(Windows.UI.Colors.White);
pointerInfo.Children.Add(pointerDetails);
pointerDetails.Text = queryPointer(e);
}
void updateInfoPop(PointerRoutedEventArgs e)
{
foreach (TextBlock pointerDetails in pointerInfo.Children)
{
if (pointerDetails.Name == e.Pointer.PointerId.ToString())
{
pointerDetails.Text = queryPointer(e);
}
}
}
String queryPointer(PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint currentPoint = e.GetCurrentPoint(targetContainer);
String details = "";
switch (e.Pointer.PointerDeviceType)
{
case Windows.Devices.Input.PointerDeviceType.Mouse:
details += "\nPointer type: mouse";
break;
case Windows.Devices.Input.PointerDeviceType.Pen:
details += "\nPointer type: pen";
if (e.Pointer.IsInContact)
{
details += "\nPressure: " + currentPoint.Properties.Pressure;
details += "\nrotation: " + currentPoint.Properties.Orientation;
details += "\nTilt X: " + currentPoint.Properties.XTilt;
details += "\nTilt Y: " + currentPoint.Properties.YTilt;
details += "\nBarrel button pressed: " + currentPoint.Properties.IsBarrelButtonPressed;
}
break;
case Windows.Devices.Input.PointerDeviceType.Touch:
details += "\nPointer type: touch";
details += "\nrotation: " + currentPoint.Properties.Orientation;
details += "\nTilt X: " + currentPoint.Properties.XTilt;
details += "\nTilt Y: " + currentPoint.Properties.YTilt;
break;
default:
details += "\nPointer type: n/a";
break;
}
GeneralTransform gt = targetContainer.TransformToVisual(page);
Point screenPoint;
screenPoint = gt.TransformPoint(new Point(currentPoint.Position.X, currentPoint.Position.Y));
details += "\nPointer Id: " + currentPoint.PointerId.ToString() +
"\nPointer location (parent): " + currentPoint.Position.X + ", " + currentPoint.Position.Y +
"\nPointer location (screen): " + screenPoint.X + ", " + screenPoint.Y;
return details;
}
}
}
我将 Mark Hall 的答案改编为单独的课程，并处理向上、向下、向左和向右滑动。它仍然存在问题，您可以在不同时间抬起手指并获得多个事件并且可以改进，尽管它可以满足我的需求：
public enum DirectionSwiped
{
None,
Up,
Down,
Left,
Right
}
public class SwipeEventArgs : EventArgs
{
public DirectionSwiped Direction { get; set; }
public int NumberOfTouches { get; set; }
}
public class SwipeGestureDetector
{
public EventHandler<SwipeEventArgs> SwipeDetected;
// How much of the grid needs to be covered by the swipe?
private const double SWIPE_THRESHOLD = 0.5;
// How much drift is allowed in the opposite axis?
private const int ALLOWED_DRIFT = 100;
Windows.Devices.Input.TouchCapabilities SupportedContacts = new Windows.Devices.Input.TouchCapabilities();
uint numActiveContacts;
Dictionary<uint, Windows.UI.Input.PointerPoint> contacts;
Dictionary<uint, Point> startLocation;
Dictionary<uint, DirectionSwiped> pointSwiped;
private Grid mGrid;
public SwipeGestureDetector(Grid grid)
{
mGrid = grid;
numActiveContacts = 0;
contacts = new Dictionary<uint, Windows.UI.Input.PointerPoint>((int)SupportedContacts.Contacts);
startLocation = new Dictionary<uint, Point>((int)SupportedContacts.Contacts);
pointSwiped = new Dictionary<uint, DirectionSwiped>((int)SupportedContacts.Contacts);
grid.PointerPressed += new PointerEventHandler(Grid_PointerPressed);
grid.PointerEntered += new PointerEventHandler(Grid_PointerEntered);
grid.PointerReleased += new PointerEventHandler(Grid_PointerReleased);
grid.PointerExited += new PointerEventHandler(Grid_PointerExited);
grid.PointerCanceled += new PointerEventHandler(Grid_PointerCanceled);
grid.PointerCaptureLost += new PointerEventHandler(Grid_PointerCaptureLost);
grid.PointerMoved += new PointerEventHandler(Grid_PointerMoved);
}
// PointerPressed and PointerReleased events do not always occur in pairs.
// Your app should listen for and handle any event that might conclude a pointer down action
// (such as PointerExited, PointerCanceled, and PointerCaptureLost).
void Grid_PointerPressed(object sender, PointerRoutedEventArgs e)
{
if (Convert.ToBoolean(SupportedContacts.TouchPresent) && (numActiveContacts > SupportedContacts.Contacts))
{
// cannot support more contacts
Debug.WriteLine("\nNumber of contacts exceeds the number supported by the device.");
return;
}
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(mGrid);
// Check if pointer already exists (if enter occurred prior to down).
if (contacts.ContainsKey(pt.PointerId))
{
return;
}
contacts[pt.PointerId] = pt;
startLocation[pt.PointerId] = pt.Position;
pointSwiped[pt.PointerId] = DirectionSwiped.None;
++numActiveContacts;
e.Handled = true;
}
private void Grid_PointerEntered(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(mGrid);
// Check if pointer already exists (if enter occurred prior to down).
if (contacts.ContainsKey(pt.PointerId))
{
return;
}
// Push new pointer Id onto expando target pointers array.
contacts[pt.PointerId] = pt;
startLocation[pt.PointerId] = pt.Position;
pointSwiped[pt.PointerId] = DirectionSwiped.None;
++numActiveContacts;
e.Handled = true;
}
// Fires for for various reasons, including:
// - User interactions
// - Programmatic caputre of another pointer
// - Captured pointer was deliberately released
// PointerCaptureLost can fire instead of PointerReleased.
private void Grid_PointerCaptureLost(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(mGrid);
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
e.Handled = true;
}
// Fires for for various reasons, including:
// - A touch contact is canceled by a pen coming into range of the surface.
// - The device doesn't report an active contact for more than 100ms.
// - The desktop is locked or the user logged off.
// - The number of simultaneous contacts exceeded the number supported by the device.
private void Grid_PointerCanceled(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(mGrid);
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
e.Handled = true;
}
private void Grid_PointerExited(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(mGrid);
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
e.Handled = true;
}
void Grid_PointerReleased(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint pt = e.GetCurrentPoint(mGrid);
if (contacts.ContainsKey(pt.PointerId))
{
checkSwipe();
contacts[pt.PointerId] = null;
contacts.Remove(pt.PointerId);
startLocation.Remove(pt.PointerId);
if (pointSwiped.ContainsKey(pt.PointerId))
pointSwiped.Remove(pt.PointerId);
--numActiveContacts;
}
e.Handled = true;
}
private void Grid_PointerMoved(object sender, PointerRoutedEventArgs e)
{
Windows.UI.Input.PointerPoint currentPoint = e.GetCurrentPoint(mGrid);
if (currentPoint.IsInContact)
{
if (startLocation.ContainsKey(currentPoint.PointerId))
{
Point startPoint = startLocation[currentPoint.PointerId];
// Compare startPoint to current location and determine if that point did a swipe?
double horizontalMovement = currentPoint.Position.X - startPoint.X;
double verticalMovement = currentPoint.Position.Y - startPoint.Y;
double horizontalDistance = Math.Abs(horizontalMovement);
double verticalDistance = Math.Abs(verticalMovement);
double requiredLeftMovement = mGrid.ActualWidth * SWIPE_THRESHOLD * -1;
double requiredRightMovement = mGrid.ActualWidth * SWIPE_THRESHOLD;
double requiredUpMovement = mGrid.ActualHeight * SWIPE_THRESHOLD * -1;
double requiredDownMovement = mGrid.ActualHeight * SWIPE_THRESHOLD;
if (verticalMovement < requiredUpMovement && horizontalDistance < 100)
{
pointSwiped[currentPoint.PointerId] = DirectionSwiped.Up;
}
else if (verticalMovement > requiredDownMovement && horizontalDistance < ALLOWED_DRIFT)
{
pointSwiped[currentPoint.PointerId] = DirectionSwiped.Down;
}
else if (horizontalMovement > requiredRightMovement && verticalDistance < ALLOWED_DRIFT)
{
pointSwiped[currentPoint.PointerId] = DirectionSwiped.Right;
}
else if (horizontalMovement < requiredLeftMovement && verticalDistance < ALLOWED_DRIFT)
{
pointSwiped[currentPoint.PointerId] = DirectionSwiped.Left;
}
}
}
}
void checkSwipe()
{
NotififyListenerIfSwiped(DirectionSwiped.Up);
NotififyListenerIfSwiped(DirectionSwiped.Down);
NotififyListenerIfSwiped(DirectionSwiped.Left);
NotififyListenerIfSwiped(DirectionSwiped.Right);
}
private void NotififyListenerIfSwiped(DirectionSwiped direction)
{
int fingers = numberOfSwipedFingers(direction);
if (fingers >= 1)
{
if (SwipeDetected != null)
{
SwipeDetected(this, new SwipeEventArgs() { Direction = direction, NumberOfTouches = fingers });
}
}
if (fingers > 0)
pointSwiped.Clear();
}
int numberOfSwipedFingers(DirectionSwiped direction)
{
int count = 0;
foreach (var item in pointSwiped)
{
DirectionSwiped swipe = item.Value;
if (swipe == direction)
{
count += 1;
}
}
return count;
}
}
用法
public void Gesture_Detected(Object sender, SwipeEventArgs e)
{
Debug.WriteLine("Number of touches: " + e.NumberOfTouches + " Direction: " + e.Direction);
}
public MainPage()
{
this.InitializeComponent();
SwipeGestureDetector gestureDetector = new SwipeGestureDetector(this.rootGrid);
gestureDetector.SwipeDetected += Gesture_Detected;