触屏事件

iphone ipad开发： 关于触屏事件的一些操作

//轻击：

//需要在你的ViewController里重写几个方法：

//开始触摸的方法

- (void)touchesBegan:(NSSet *)touches

           withEvent:(UIEvent *)event

{

messageLabel.text = @”Touches Began”;

[self updateLabelsFromTouches:touches];

}

//触摸取消的方法

- (void)touchesCancelled:(NSSet *)touches

               withEvent:(UIEvent *)event

{

messageLabel.text = @”Touches Cancelled”;

[self updateLabelsFromTouches:touches];

}

//触摸结束的方法

- (void)touchesEnded:(NSSet *)touches

           withEvent:(UIEvent *)event

{

messageLabel.text = @”Touches Stopped.”;

[self updateLabelsFromTouches:touches];

}

//触摸移动的方法

- (void)touchesMoved:(NSSet *)touches

           withEvent:(UIEvent *)event

{

messageLabel.text = @”Drag Detected”;

[self updateLabelsFromTouches:touches];

}

//触摸－清扫：

//开始触摸

- (void)touchesBegan:(NSSet *)touches

           withEvent:(UIEvent *)event

{

UITouch *touch = [touches anyObject];

gestureStartPoint = [touch locationInView:self.view];

}

//kMinimumGestureLength 最小移动长度 kMaximumVariance最大偏移长度

- (void)touchesMoved:(NSSet *)touches

           withEvent:(UIEvent *)event

{

UITouch *touch = [touches anyObject];

CGPoint currentPosition = [touchlocationInView:self.view];

CGFloat deltaX = fabsf(gestureStartPoint.x - currentPosition.x);

CGFloat deltaY = fabsf(gestureStartPoint.y - currentPosition.y);

if(deltaX >= kMinimumGestureLength && deltaY <= kMaximumVariance)

{

label.text = @”Horizontal swipe detected”;

[self performSelector:@selector(eraseText)

 withObject:nilafterDelay:2];

}

else if (deltaY >= kMinimumGestureLength &&

deltaX <= kMaximumVariance)

{

label.text = @”Vertical swipe detected”;

[selfperformSelector:@selector(eraseText)withObject:nilafterDelay:2];

}

}

//多次轻击判断，比如双击，三击等：

//单击动作响应事件

- (void)singleTap

{

singleLabel.text = @”Single Tap Detected”;

[selfperformSelector:@selector(eraseMe:)

          withObject:singleLabel

          afterDelay:1.6f];//1.6秒后执行eraseMe方法

}

//双击

- (void)doubleTap

{

doubleLabel.text = @”Double Tap Detected”;

[selfperformSelector:@selector(eraseMe:)

          withObject:doubleLabel

          afterDelay:1.6f];

}

//三击

- (void)tripleTap

{

tripleLabel.text = @”Triple Tap Detected”;

[selfperformSelector:@selector(eraseMe:)

  withObject:tripleLabel

  afterDelay:1.6f];

}

//四击

- (void)quadrupleTap

{

quadrupleLabel.text = @”Quadruple Tap Detected”;

[selfperformSelector:@selector(eraseMe:)

  withObject:quadrupleLabel

  afterDelay:1.6f];

}

- (void)eraseMe:(UITextField *)textField

{

textField.text = @"";

}

- (void)touchesBegan:(NSSet *)touches

  withEvent:(UIEvent *)event

{

UITouch *touch = [touches anyObject];   //实例一个uitouch

NSUInteger tapCount = [touch tapCount]; //计算touch的tapCount次数

switch (tapCount)

{

case 1:

[selfsingleTap];

break;

case 2:

[selfdoubleTap];

break;

case 3:

[selftripleTap];

break;

case 4:

[selfquadrupleTap];

break;

default:

break;

}

}

//[self performSelector:@selector(eraseMe:)withObject:singleLabel afterDelay:1.6f]中

//performSelector:@selector(eraseMe:)withObject:singleLabel afterDelay:1.6f方法为将来afterDelay1.6秒之后调用eraseMe方法

//同样的[NSObect  cancelPreviousPerformSelector:withObject :afterDelay:];

//方法为取消这些将来的调用

//捏合操作：

- (void)eraseLabel

{ //清空lable

label.text = @"";

}

//开始触碰

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

if([touches count] ==2)

{ //检测是否为两个手指触点

NSArray *twoTouches = [touchesallObjects];

UITouch *first = [twoTouchesobjectAtIndex:0];

UITouch *second = [twoTouchesobjectAtIndex:1];

initialDistance = distanceBetweenPoints(

[first locationInView:self.view], [secondlocationInView:self.view]);

}

}

//移动手指

- (void)touchesMoved:(NSSet *)touches

  withEvent:(UIEvent *)event

{

if ([touches count] == 2)

{

NSArray *twoTouches = [touchesallObjects];

UITouch *first = [twoTouchesobjectAtIndex:0];

UITouch *second = [twoTouchesobjectAtIndex:1];

CGFloat currentDistance =distanceBetweenPoints(

[first locationInView:self.view],[secondlocationInView:self.view]);

if (initialDistance ==0)

{

initialDistance = currentDistance;//根据移动前后的坐标距离差检测是捏合的手势还是打开的手势

}

else if (currentDistance - initialDistance > kMinimumPinchDelta)

{ //检测是否大于最小移动值kMinimumPinchDelta

label.text = @”Outward Pinch”;

[selfperformSelector:@selector(eraseLabel)

 withObject:nil

  afterDelay:1.6f];

}

else if (initialDistance - currentDistance > kMinimumPinchDelta)

{

label.text = @”Inward Pinch”;

[selfperformSelector:@selector(eraseLabel)

 withObject:nil

  afterDelay:1.6f];

}

}

}

//触碰结束

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event

{

initialDistance = 0;

}

//自定义手势“√”：

- (void)eraseLabel

{

label.text = @"";

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

UITouch *touch = [touches anyObject];

CGPoint point = [touch locationInView:self.view];

lastPreviousPoint = point;

lastCurrentPoint = point;

lineLengthSoFar = 0.0f;

}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event

{

UITouch *touch = [touches anyObject];

CGPoint previousPoint = [touchpreviousLocationInView:self.view];

CGPoint currentPoint = [touch locationInView:self.view];

//计算两条线之间的角度

CGFloat angle = angleBetweenLines(lastPreviousPoint,

          lastCurrentPoint,previousPoint,currentPoint);

//检测手势被承认的条件 kMinimumCheckMarkAngle最小角度

//kMaximumCheckMarkAngle最大角度

//kMinimumCheckMarkLength画线最小长度

if (angle >= kMinimumCheckMarkAngle &&

angle <= kMaximumCheckMarkAngle &&

lineLengthSoFar > kMinimumCheckMarkLength)

{

label.text = @”Checkmark”;

[selfperformSelector:@selector(eraseLabel)

 withObject:nil

  afterDelay:1.6];

}

//lineLengthSoFar,lastPreviousPoint,lastCurrentPoint重新赋值

lineLengthSoFar += distanceBetweenPoints(previousPoint, currentPoint);

lastPreviousPoint = previousPoint;

lastCurrentPoint = currentPoint;

}

//这里用到一个判断两条直线的角度的方法

//angleBetweenLines(CGPoint line1Start, CGPoint line1End, CGPoint line2Start, CGPointlin2End);

//给一个几何方法集的接口方法：

//CGPointUtils.h 头文件

#import <CoreGraphics/CoreGraphics.h>

CGFloat distanceBetweenPoints (CGPoint first,CGPoint second);

CGFloat angleBetweenPoints(CGPoint first, CGPoint second);

CGFloat angleBetweenLines(CGPoint line1Start,CGPoint line1End, CGPoint line2Start,CGPoint lin2End);

//.c文件 CGPointUtils.c

#include ”CGPointUtils.h”

#include <math.h>

#define pi 3.14159265358979323846

#define degreesToRadian(x) (pi * x / 180.0)

#define radiansToDegrees(x) (180.0 * x / pi)

CGFloat distanceBetweenPoints (CGPoint first,CGPoint second)

{

CGFloat deltaX = second.x - first.x;

CGFloat deltaY = second.y - first.y;

return sqrt(deltaX*deltaX + deltaY*deltaY );

};

CGFloat angleBetweenPoints(CGPoint first, CGPoint second)

{

CGFloat height = second.y - first.y;

CGFloat width = first.x - second.x;

CGFloat rads = atan(height/width);

returnradiansToDegrees(rads);

//degs = degrees(atan((top – bottom)/(right – left)))

}

CGFloat angleBetweenLines(CGPoint line1Start,CGPoint line1End, CGPoint line2Start,CGPoint line2End)

{

CGFloat a = line1End.x - line1Start.x;

CGFloat b = line1End.y - line1Start.y;

CGFloat c = line2End.x - line2Start.x;

CGFloat d = line2End.y - line2Start.y;

CGFloat rads = acos(((a*c) + (b*d)) / ((sqrt(a*a + b*b)) * (sqrt(c*c + d*d))));

returnradiansToDegrees(rads);

}