UIView not dragging smoothly by UIpangesture when use autolayout constraint - objective-c

Question

**I want to drag a view up vertically using UIpangesture. As my project includes autolayout, I created 4 layout constraint [top, right, bottom, left] and create an outlet from topspace constraint. When gesture recognize, topspaceConstraint's constant is chnage to change the views orgin Y. The code works but dragging is not smooth. How can I make it smooth **
-(void)gestureAction:(UIPanGestureRecognizer *)gesture
{
CGFloat targetY = 0;
if(gesture.state == UIGestureRecognizerStateBegan)
{
self.panCoord = [gesture locationInView:gesture.view];
}
CGPoint newCoord = [gesture locationInView:gesture.view];
float dY = newCoord.y-self.panCoord.y;
float newOriginY = (gesture.view.frame.origin.y+dY);
dispatch_async(dispatch_get_main_queue(), ^(void){
self.propertyDetailContentViewTopConstraint.constant = newOriginY;
});
if (gesture.state == UIGestureRecognizerStateEnded) {
if (gesture.view.frame.origin.y*0.8 < 100) {
targetY = 0;
}else if (gesture.view.frame.origin.y*0.8 < 250){
targetY = 250;
}else{
targetY = MAIN_SCREEN_HEIGHT;
}
[self setPropertyDetailContentViewTopConstraintTop:targetY];
}
}
-(void)setPropertyDetailContentViewTopConstraintTop:(CGFloat)top
{
[self.view layoutIfNeeded];
self.propertyDetailContentViewTopConstraint.constant = top;
[UIView animateWithDuration:0.5
animations:^{
[self.view layoutIfNeeded];
}];
}

Answer 1

#Rokon please use following code may be its help to you. Please use your view instead of "DrawImageView"
-(void)moveViewWithGestureRecognizer:(UIPanGestureRecognizer *)panGestureRecognizer{
NSUInteger touches = panGestureRecognizer.numberOfTouches;
CGPoint translation = [panGestureRecognizer translationInView:self.view];
self.DrawImageView.center = CGPointMake(self.DrawImageView.center.x + translation.x,
self.DrawImageView.center.y + translation.y);
[panGestureRecognizer setTranslation:CGPointMake(0, 0) inView:self.view];
if (panGestureRecognizer.state == UIGestureRecognizerStateEnded) {
CGPoint velocity = [panGestureRecognizer velocityInView:self.view];
CGFloat magnitude = sqrtf((velocity.x * velocity.x) + (velocity.y * velocity.y));
CGFloat slideMult = magnitude / 200;
// NSLog(#"magnitude: %f, slideMult: %f", magnitude, slideMult);
float slideFactor = 0.1 * slideMult; // Increase for more of a slide
CGPoint finalPoint = CGPointMake(self.DrawImageView.center.x + (velocity.x * slideFactor),
self.DrawImageView.center.y + (velocity.y * slideFactor));
finalPoint.x = MIN(MAX(finalPoint.x, 0), self.view.bounds.size.width);
finalPoint.y = MIN(MAX(finalPoint.y, 0), self.view.bounds.size.height);
[UIView animateWithDuration:slideFactor*2 delay:0 options:UIViewAnimationOptionCurveEaseOut animations:^{
self.DrawImageView.center = finalPoint;
} completion:nil];
// [self.frontImageView setAlpha:1.0];
}
}