Objective c 如果没有UIScrollView,如何在UIImageView中进行放大和缩小?
我正在为iOS 4.2开发一个应用程序,iPhone,在这个应用程序中我下载图像并将它们保存在内部存储器(NSDocuments)中 那么,我在UIImageView中显示第一个图像。用户可以在UIImageView(触摸移动)上拖动手指,当用户这样做时,我加载其他图像。如果用户向下拖动,我将加载一个图像,如果向上拖动,我将加载另一个图像,还将加载左右图像 这一切都完成了。但我想实现缩放。这是我到目前为止的代码: initialDistance-->是第一次触摸时手指之间的距离Objective c 如果没有UIScrollView,如何在UIImageView中进行放大和缩小?,objective-c,uiimageview,ios-4.2,zooming,Objective C,Uiimageview,Ios 4.2,Zooming,我正在为iOS 4.2开发一个应用程序,iPhone,在这个应用程序中我下载图像并将它们保存在内部存储器(NSDocuments)中 那么,我在UIImageView中显示第一个图像。用户可以在UIImageView(触摸移动)上拖动手指,当用户这样做时,我加载其他图像。如果用户向下拖动,我将加载一个图像,如果向上拖动,我将加载另一个图像,还将加载左右图像 这一切都完成了。但我想实现缩放。这是我到目前为止的代码: initialDistance-->是第一次触摸时手指之间的距离 FinalIns
FinalInstance-->是手指每次移动时的距离
x-->为0
y-->为0
// this method calculate the distance between 2 fingers
- (CGFloat)distanceBetweenTwoPoints:(CGPoint)fromPoint toPoint:(CGPoint)toPoint {
float xPoint = toPoint.x - fromPoint.x;
float yPoint = toPoint.y - fromPoint.y;
return sqrt(xPoint * xPoint + yPoint * yPoint);
}
//------------------- Movimientos con los dedos ------------------------------------
#pragma mark -
#pragma mark UIResponder
// First Touch
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSSet *allTouches = [event allTouches];
switch ([allTouches count]) {
case 1: { //Single touch
//Get the first touch.
UITouch *touch1 = [[allTouches allObjects] objectAtIndex:0];
switch ([touch1 tapCount])
{
case 1: //Single Tap.
{
// Guardo la primera localización del dedo cuando pulsa por primera vez
//inicial = [touch1 locationInView:self.view];
} break;
case 2: {//Double tap.
//Track the initial distance between two fingers.
//if ([[allTouches allObjects] count] >= 2) {
// oculto/o no, la barra de arriba cuando se hace un dobleTap
//[self switchToolBar];
} break;
}
} break;
case 2: { //Double Touch
// calculo la distancia inicial que hay entre los dedos cuando empieza a tocar
UITouch *touch1 = [[allTouches allObjects] objectAtIndex:0];
UITouch *touch2 = [[allTouches allObjects] objectAtIndex:1];
initialDistance = [self distanceBetweenTwoPoints:[touch1 locationInView:[self view]]
toPoint:[touch2 locationInView:[self view]]];
}
default:
break;
}
}
// when the finger/s move to
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
NSSet *allTouches = [event allTouches];
switch ([allTouches count])
{
case 1: {
} break;
case 2: {
//The image is being zoomed in or out.
UITouch *touch1 = [[allTouches allObjects] objectAtIndex:0];
UITouch *touch2 = [[allTouches allObjects] objectAtIndex:1];
//Calculate the distance between the two fingers.
CGFloat finalDistance = [self distanceBetweenTwoPoints:[touch1 locationInView:[self view]]
toPoint:[touch2 locationInView:[self view]]];
NSLog(@"Distancia Inicial :: %.f, Ditancia final :: %.f", initialDistance, finalDistance);
float factorX = 20.0;
float factorY = 11.0;
// guardo la posicion de los 2 dedos
//CGPoint dedo1 = [[[touches allObjects] objectAtIndex:0] locationInView:self.view];
//CGPoint dedo2 = [[[touches allObjects] objectAtIndex:1] locationInView:self.view];
// comparo para saber si el usuario esta haciendo zoom in o zoom out
if(initialDistance < finalDistance) {
NSLog(@"Zoom In");
float newWidth = imagen.frame.size.width + (initialDistance - finalDistance + factorX);
float newHeight = imagen.frame.size.height + (initialDistance - finalDistance + factorY);
if (newWidth <= 960 && newHeight <= 640) {
/*
if (dedo1.x >= dedo2.x) {
x = (dedo1.x + finalDistance/2);
y = (dedo1.y + finalDistance/2);
} else {
x = (dedo2.x + finalDistance/2);
y = (dedo2.y + finalDistance/2);
}
*/
//x = (dedo1.x);
//y = (dedo1.y);
imagen.frame = CGRectMake( x, y, newWidth, newHeight);
} else {
imagen.frame = CGRectMake( x, y, 960, 640);
}
}
else {
NSLog(@"Zoom Out");
float newWidth = imagen.frame.size.width - (finalDistance - initialDistance + factorX);
float newHeight = imagen.frame.size.height - (finalDistance - initialDistance + factorY);
if (newWidth >= 480 && newHeight >= 320) {
/*
if (dedo1.x >= dedo2.x) {
x = (dedo1.x + finalDistance/2);
y = (dedo1.y + finalDistance/2);
} else {
x = (dedo2.x + finalDistance/2);
y = (dedo2.y + finalDistance/2);
}
*/
//x -= (finalDistance - initialDistance + factorX);
//y -= (finalDistance - initialDistance + factorX);
//x = (dedo1.x);
//y = (dedo1.y);
imagen.frame = CGRectMake( x, y, newWidth, newHeight);
} else {
imagen.frame = CGRectMake( 0, 0, 480, 320);
}
}
initialDistance = finalDistance;
} break;
}
}
#pragma mark -
//此方法计算两个手指之间的距离
-(CGFloat)两点之间的距离:(CGPoint)fromPoint toPoint:(CGPoint)toPoint{
float xPoint=toPoint.x-fromPoint.x;
float yPoint=toPoint.y—fromPoint.y;
返回sqrt(xPoint*xPoint+yPoint*yPoint);
}
//-------------------康洛斯德多斯酒店------------------------------------
#布拉格标记-
#pragma标记应答器
//第一次接触
-(无效)触摸开始:(NSSet*)触摸事件:(UIEvent*)事件{
NSSet*AllTouchs=[event AllTouchs];
开关([AllTouchs计数]){
案例1:{//单触
//第一次接触。
UITouch*touch1=[[AllTouchs AllObject]对象索引:0];
开关([touch1 tapCount])
{
案例1://单抽头。
{
//在当地,你可以看到一辆豪华轿车
//inical=[touch1 locationInView:self.view];
}中断;
案例2:{//双击。
//跟踪两个手指之间的初始距离。
//如果([[AllTouchs AllObject]计数]>=2){
//眼睛/不,在多布勒塔普附近
//[自动切换工具栏];
}中断;
}
}中断;
案例2:{//Double-Touch
//距离计算是一种特殊的计算方法
UITouch*touch1=[[AllTouchs AllObject]对象索引:0];
UITouch*touch2=[[AllTouchs AllObject]对象索引:1];
initialDistance=[两点之间的自距离:[触摸1位置查看:[自查看]]
toPoint:[touch2 locationInView:[self view]];
}
违约:
打破
}
}
//当手指移动到
-(无效)触摸移动:(NSSet*)触摸事件:(UIEvent*)事件
{
NSSet*AllTouchs=[event AllTouchs];
开关([AllTouchs计数])
{
案例1:{
}中断;
案例2:{
//正在放大或缩小图像。
UITouch*touch1=[[AllTouchs AllObject]对象索引:0];
UITouch*touch2=[[AllTouchs AllObject]对象索引:1];
//计算两个手指之间的距离。
CGFloat finalDistance=[两点之间的自我距离:[触摸1位置查看:[自我查看]]
toPoint:[touch2 locationInView:[self view]];
NSLog(@“初始距离:%.f,最终距离:%.f”,初始距离,最终距离);
浮动系数x=20.0;
浮子工厂=11.0;
//2号德多斯酒店
//CGPoint dedo1=[[[touchs allObjects]objectAtIndex:0]locationInView:self.view];
//CGPoint dedo2=[[touchs allObjects]objectAtIndex:1]locationInView:self.view];
//比较刀的大小,放大或缩小
if(初始距离<最终距离){
NSLog(@“放大”);
float newWidth=imagen.frame.size.width+(初始距离-最终距离+系数x);
float newHeight=imagen.frame.size.height+(初始距离-最终距离+工厂);
如果(newWidth=480&&newHeight>=320){
/*
如果(dedo1.x>=dedo2.x){
x=(dedo1.x+最终立场/2);
y=(dedo1.y+最终立场/2);
}否则{
x=(dedo2.x+finalDistance/2);
y=(dedo2.y+最终立场/2);
}
*/
//x-=(最终距离-初始距离+系数x);
//y-=(最终距离-初始距离+系数x);
//x=(dedo1.x);
//y=(dedo1.y);
imagen.frame=CGRectMake(x,y,newWidth,newHeight);
}否则{
imagen.frame=CGRectMake(0,0480320);
}
}
初始距离=最终距离;
}中断;
}
}
#布拉格标记-
非常感谢
PD:如果有一个UISCLVIEW WHTCH的方法,我可以在不同的图像之间移动,我也会打开看看。
OK。如果只使用它的缩放功能,你可以考虑使用UISCLVIEW。 假设我们有一个
scrollView
和一个imageView
,两者的边界相同。将imageView
添加为scrollView
的子视图
[scrollView addSubview:imageView];
scrollView.contentSize = imageView.frame.size;
要在scrollView
中仅支持缩放而不支持平移,您的viewController
必须采用UIScrollViewDelegate
协议
// Disabling panning/scrolling in the scrollView
scrollView.scrollEnabled = NO;
// For supporting zoom,
scrollView.minimumZoomScale = 0.5;
scrollView.maximumZoomScale = 2.0;
...
// Implement a single scroll view delegate method
- (UIView*)viewForZoomingInScrollView:(UIScrollView *)aScrollView {
return imageView;
}
现在我们已经有了缩放功能。对于滑动,您可以使用适当的配置。创建一个手势来处理每个滑动方向,并将其添加到滚动视图中
UISwipeGestureRecognizer *rightSwipe = [[UISwipeGestureRecognizer alloc] initWithTarget:self selector:@selector(handleRightSwipe:)];
rightSwipe.direction = UISwipeGestureRecognizerDirectionRight;
rightSwipe.numberOfTouchesRequired = 1;
[scrollView addGesture:rightSwipe];
[rightSwipe release];
然后根据手势检索适当的图像,并使用
imageView.image=yourImage;
进行设置。最后,在Deepak的帮助下,我使用UIImageView的transform属性进行缩放
我使用CGAffineTransform矩阵中[0,0]位置的CGFloat来设置限制。我必须在放大时将CGFloat传递给字符串,因为当我将其与0进行比较时,这是alwa
// comparo para saber si el usuario esta haciendo zoom in o zoom out
if(initialDistance < finalDistance) {
NSLog(@"Zoom Out");
CGAffineTransform transformer = CGAffineTransformScale(imagen.transform, 1.05, 1.05);
NSLog(@"transformer :: A: %.f, B: %.f, C: %.f, D: %.f", imagen.transform.a, imagen.transform.b, imagen.transform.c, imagen.transform.d);
if (transformer.a < 5) {
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration: 0.2];
imagen.transform = transformer;
[UIView setAnimationDelegate:self];
[UIView commitAnimations];
}
}
else {
NSLog(@"Zoom In");
CGAffineTransform transformer = CGAffineTransformScale(imagen.transform, 0.95, 0.95);
NSLog(@"transformer :: A: %.f, B: %.f, C: %.f, D: %.f", transformer.a, transformer.b, transformer.c, transformer.d);
NSString *num = [NSString stringWithFormat:@"%.f", transformer.a];
if (![num isEqualToString:@"0"]) {
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration: 0.2];
imagen.transform = transformer;
[UIView setAnimationDelegate:self];
[UIView commitAnimations];
}
}