Photo gallery functionality - objective-c

Question

I need to simulate the photo gallery effects.
I have uiimageview, I need to zoom in and out, scale and - if I double tapped (or shook the iPad - I want the image to return to its actual size.
I tried a lot, but all the available examples are buggy and not complete; I don't want to use uiwebview.
Any suggestion, please?
here's the code
in view did load
:
holderView = [[UIView alloc] initWithFrame:CGRectMake(0,0,self.view.bounds.size.width,self.view.bounds.size.height)];
imageview = [[UIImageView alloc] initWithFrame:[holderView frame]];
[imageview setImage:myimage];
imageview.contentMode = UIViewContentModeScaleAspectFit;
//holderView.contentMode = UIViewContentModeScaleAspectFit ;
[holderView addSubview:imageview];
UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(scale:)];
[pinchRecognizer setDelegate:self];
[holderView addGestureRecognizer:pinchRecognizer];
UIRotationGestureRecognizer *rotationRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:#selector(rotate:)];
[rotationRecognizer setDelegate:self];
[holderView addGestureRecognizer:rotationRecognizer];
UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(move:)];
[panRecognizer setMinimumNumberOfTouches:1];
[panRecognizer setMaximumNumberOfTouches:1];
[panRecognizer setDelegate:self];
[holderView addGestureRecognizer:panRecognizer];
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapped:)];
[tapRecognizer setNumberOfTapsRequired:1];
[tapRecognizer setDelegate:self];
[holderView addGestureRecognizer:tapRecognizer];
and the following is the code I use for the functions
-(void)scale:(id)sender {
[self.view bringSubviewToFront:[(UIPinchGestureRecognizer*)sender view]];
if(zooming)
{
if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
lastScale = 1.0;
return;
}
CGFloat scale = 1.0 - (lastScale - [(UIPinchGestureRecognizer*)sender scale]);
CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);
[[(UIPinchGestureRecognizer*)sender view] setTransform:newTransform];
lastScale = [(UIPinchGestureRecognizer*)sender scale];
OldTransform = newTransform;
OldCenter = [(UIPinchGestureRecognizer*)sender view].center;
Does_Panned = YES ;
Does_transformed = YES ;
}
else {
}
}
-(void)rotate:(id)sender {
if(zooming)
{
[self.view bringSubviewToFront:[(UIRotationGestureRecognizer*)sender view]];
if([(UIRotationGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
lastRotation = 0.0;
return;
}
CGFloat rotation = 0.0 - (lastRotation - [(UIRotationGestureRecognizer*)sender rotation]);
CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform;
CGAffineTransform newTransform = CGAffineTransformRotate(currentTransform,rotation);
[[(UIRotationGestureRecognizer*)sender view] setTransform:newTransform];
lastRotation = [(UIRotationGestureRecognizer*)sender rotation];
OldTransform = newTransform ;
OldCenter = [(UIPinchGestureRecognizer*)sender view].center;
Does_Panned = YES ;
Does_transformed = YES ;
}
}
-(void)move:(id)sender {
if(zooming)
{
[[[(UITapGestureRecognizer*)sender view] layer] removeAllAnimations];
[self.view bringSubviewToFront:[(UIPanGestureRecognizer*)sender view]];
CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view];
if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {
firstX = [[sender view] center].x;
firstY = [[sender view] center].y;
}
translatedPoint = CGPointMake(firstX+translatedPoint.x, firstY+translatedPoint.y);
[[sender view] setCenter:translatedPoint];
OldCenter = translatedPoint ;
Does_Panned = YES ;
Does_transformed = NO ;
if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
CGFloat finalX = translatedPoint.x + (.35*[(UIPanGestureRecognizer*)sender velocityInView:self.view].x);
CGFloat finalY = translatedPoint.y + (.35*[(UIPanGestureRecognizer*)sender velocityInView:self.view].y);
if(UIDeviceOrientationIsPortrait([[UIDevice currentDevice] orientation])) {
if(finalX < 0) {
finalX = 0;
}
else if(finalX > 768) {
finalX = 768;
}
if(finalY < 0) {
finalY = 0;
}
else if(finalY > 1024) {
finalY = 1024;
}
}
else {
if(finalX < 0) {
finalX = 0;
}
else if(finalX > 1024) {
finalX = 768;
}
if(finalY < 0) {
finalY = 0;
}
else if(finalY > 768) {
finalY = 1024;
}
}
[UIView beginAnimations:nil context:NULL];
//[UIView setAnimationDelay: 1.0];
[UIView setAnimationDuration:.20];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
//[[sender view] setCenter:CGPointMake(finalX, finalY)];
[UIView commitAnimations];
}
}
else{
if([(UIPanGestureRecognizer*)sender maximumNumberOfTouches] == 1)
{
UIPanGestureRecognizer* recognize = (UIPanGestureRecognizer*)sender;
//change the current window width and level
if([recognize state] == UIGestureRecognizerStateBegan) {
Bigen =[recognize translationInView:recognize.view ];// [[sender view] center];
BeginX = Bigen.x;
BeginY = Bigen.y;
}
else if(
( [recognize state] == UIGestureRecognizerStateChanged )||
(recognize.state == UIGestureRecognizerStateEnded) )
{
CGPoint translation = [recognize translationInView:recognize.view ];
End = translation ;
EndX = End.x ;
EndY = End.y ;
double offsetw=0;
double offsetl=0;
if(EndX>BeginX)
{
offsetw=50*(EndX-BeginX);
}
else if(EndX<BeginX)
{
offsetw=50*(EndX-BeginX);
}
else
{
offsetw=0;
}
if(EndY>BeginY)
{
offsetl=50*(EndY-BeginY);
}
else if(EndY<BeginY)
{
offsetl=50*(EndY-BeginY);
}
else
{
offsetl=0;
}
ChangeWW_Wl(offsetw, offsetl);
[self AddImage];
}
//if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
/* CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view];
EndX = translatedPoint.x;
EndY = translatedPoint.y;*/
//}
}
}
}
(void)tapped:(id)sender {
if(zooming)
{
[[[(UITapGestureRecognizer*)sender view] layer] removeAllAnimations];
}
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
return ![gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]];
}
how to update it to reset the image to its original size at shaking or double tap
how to over come the improper zooming (zoom with large factor at the first time )

Answer 1

You should watch the "Designing Apps with Scroll Views" video from WWDC2010, it tells you how to do this exact thing.