#define SCREEN_WIDTH ([UIScreen mainScreen].nativeBounds.size.width / [UIScreen mainScreen].nativeScale)
#define SCREEN_HEIGHT ([UIScreen mainScreen].nativeBounds.size.height / [UIScreen mainScreen].nativeScale)
#define SMALLWIDTH self.firstSmallPreView.frame.size.width //self.firstSmallPreView为响应拖动手势的控件
#define SMALLHEIGHT self.firstSmallPreView.frame.size.height
#define animateDuration 0.3 //位置改变动画时间
//给拖动控件添加手势
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(changeLocation:)];
[self.firstSmallPreView addGestureRecognizer:pan];
[self.view addSubview:self.firstSmallPreView];
第一种：任意拖动控件靠边停留实现：
- (void)changeLocation:(UIPanGestureRecognizer *)pan{
self.firstSmallPreView = pan.view;
CGPoint panPoint = [pan locationInView:[[UIApplication sharedApplication] keyWindow]];
if(pan.state == UIGestureRecognizerStateBegan)
{
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(changeStatus) object:nil];
}
if(pan.state == UIGestureRecognizerStateChanged)
{
self.firstSmallPreView.center = CGPointMake(panPoint.x, panPoint.y);
}
else if(pan.state == UIGestureRecognizerStateEnded)
{
if(panPoint.x <= SCREEN_WIDTH/2)
{
if(panPoint.y <= 40 + SMALLHEIGHT/2 && panPoint.x >= 20 + SMALLWIDTH/2)
{
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(panPoint.x, SMALLHEIGHT/2);
}];
}
else if(panPoint.y >= SCREEN_HEIGHT - SMALLHEIGHT/2 - 40 && panPoint.x >= 20 + SMALLWIDTH/2)
{
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(panPoint.x, SCREEN_HEIGHT - SMALLHEIGHT/2);
}];
}
else if (panPoint.x < SMALLWIDTH/2+20 && panPoint.y > SCREEN_HEIGHT-SMALLHEIGHT/2)
{
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(SMALLWIDTH/2, SCREEN_HEIGHT-SMALLHEIGHT/2);
}];
}
else
{
CGFloat pointy = panPoint.y < SMALLHEIGHT/2 ? SMALLHEIGHT/2 :panPoint.y;
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(SMALLWIDTH/2, pointy);
}];
}
}
else if(panPoint.x > SCREEN_WIDTH/2)
{
if(panPoint.y <= 40 + SMALLHEIGHT/2 && panPoint.x < SCREEN_WIDTH - SMALLWIDTH/2-20 )
{
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(panPoint.x, SMALLHEIGHT/2);
}];
}
else if(panPoint.y >= SCREEN_HEIGHT - 40 - SMALLHEIGHT/2 && panPoint.x < SCREEN_WIDTH - SMALLWIDTH/2 - 20)
{
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(panPoint.x, SCREEN_HEIGHT - SMALLHEIGHT/2);
}];
}
else if (panPoint.x > SCREEN_WIDTH- SMALLWIDTH/2-20 && panPoint.y < SMALLHEIGHT/2)
{
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(SCREEN_WIDTH - SMALLWIDTH/2, SMALLHEIGHT/2);
}];
}
else
{
CGFloat pointy = panPoint.y > SCREEN_HEIGHT - SMALLHEIGHT/2 ? SCREEN_HEIGHT- SMALLHEIGHT/2 :panPoint.y;
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(SCREEN_WIDTH - SMALLWIDTH/2, pointy);
}];
}
}
}
}
- (void)changeStatus
{
[UIView animateWithDuration:0.5 animations:^{
CGFloat x = self.firstSmallPreView.center.x < 20 + SMALLWIDTH/2 ? 0 : self.firstSmallPreView.center.x > SCREEN_WIDTH - 20 - SMALLWIDTH/2 ? SCREEN_WIDTH : self.firstSmallPreView.center.x;
CGFloat y = self.firstSmallPreView.center.y < 40 + SMALLHEIGHT/2 ? 0 : self.firstSmallPreView.center.y > SCREEN_HEIGHT - 40 - SMALLHEIGHT/2 ? SCREEN_HEIGHT : self.firstSmallPreView.center.y;
//禁止停留在4个角
if((x == 0 && y ==0) || (x == SCREEN_WIDTH && y == 0) || (x == 0 && y == SCREEN_HEIGHT) || (x == SCREEN_WIDTH && y == SCREEN_HEIGHT)){
y = self.firstSmallPreView.center.y;
}
self.firstSmallPreView.center = CGPointMake(x, y);
}];
}
第二种：任意拖动，任意停留
- (void)changeLocation:(UIPanGestureRecognizer *)pan{
self.firstSmallPreView = pan.view;
CGPoint panPoint = [pan locationInView:[[UIApplication sharedApplication] keyWindow]];
if(pan.state == UIGestureRecognizerStateBegan)
{
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(changeStatus) object:nil];
}
if(pan.state == UIGestureRecognizerStateChanged)
{
self.firstSmallPreView.center = CGPointMake(panPoint.x, panPoint.y);
}
else if(pan.state == UIGestureRecognizerStateEnded)
{
CGFloat pointy = panPoint.y;
CGFloat pointx = panPoint.x;
BOOL needChangeLocation = NO;
if (panPoint.y > SCREEN_HEIGHT - SMALLHEIGHT /2) {
pointy = SCREEN_HEIGHT - SMALLHEIGHT /2;
needChangeLocation = YES;
}
if (panPoint.y < SMALLHEIGHT/2) {
pointy = SMALLHEIGHT/2;
needChangeLocation = YES;
}
if (panPoint.x > SCREEN_WIDTH - SMALLWIDTH/2) {
pointx = SCREEN_WIDTH - SMALLWIDTH/2;
needChangeLocation = YES;
}
if (panPoint.x < SMALLWIDTH/2) {
pointx = SMALLWIDTH/2;
needChangeLocation = YES;
}
if (needChangeLocation) {
[UIView animateWithDuration:animateDuration animations:^{
self.firstSmallPreView.center = CGPointMake(pointx, pointy);
}];
}
}
}
