I am working on a magazine viewer and I have to use UIWebView for pages because of html5 interactive contents. First I tried uiwebviews in a UIScrollView but scrollview was too slow on sliding pages. So now I am trying to write my own scrollview-like code. I have a MainView.xib, a view controller (Viewer) and extended UIWindow class (TouchCapturingWindow) that I take from here : http://wyldco.com/blog/2010/11/how-to-capture-touches-over-a-uiwebview/
when I try to slide pages fast, there is no problem but when I touch and slowly slide by not pulling my finger, "Viewer" view controller stops receiving touch events and so pages stop moving. I am logging TouchCapturingWindow, it still sending events. I searched many information and tutorials but I couldn't make it work. How can I make it continuously receive touch events?
I uploaded a simple Xcode project that contains only this part of my project. You can download here : http://testdergi.mysys.com/touchEvents.zip When you run project, you should first download pages (180Kb) by tapping "Download Pages" button, then tap the "Open Viewer" button.
You can also look over the code below :
TouchCapturingWindow.h :
@interface TouchCapturingWindow : UIWindow {
NSMutableArray *views;
@private
UIView *touchView;
}
- (void)addViewForTouchPriority:(UIView*)view;
- (void)removeViewForTouchPriority:(UIView*)view;
@end
TouchCapturingWindow.m :
@implementation TouchCapturingWindow
- (void)dealloc {
}
- (void)addViewForTouchPriority:(UIView*)view {
if ( !views ) views = [[NSMutableArray alloc] init];
[views addObject:view];
}
- (void)removeViewForTouchPriority:(UIView*)view {
if ( !views ) return;
[views removeObject:view];
}
- (void)sendEvent:(UIEvent *)event {
//get a touch
UITouch *touch = [[event allTouches] anyObject];
//check which phase the touch is at, and process it
if (touch.phase == UITouchPhaseBegan) {
for ( UIView *view in views ) {
//if ( CGRectContainsPoint([view frame], [touch locationInView:[view superview]]) ) {
NSLog(@"TouchCapturingWindow --> TouchPhaseBegan");
touchView = view;
[touchView touchesBegan:[event allTouches] withEvent:event];
break;
}
}
else if (touch.phase == UITouchPhaseMoved) {
NSLog(@"TouchCapturingWindow --> TouchPhaseMoved");
if ( touchView ) {
[touchView touchesMoved:[event allTouches] withEvent:event];
}
else
{
NSLog(@"touch view is nil");
}
}
else if (touch.phase == UITouchPhaseCancelled) {
NSLog(@"TouchCapturingWindow --> TouchPhaseCancelled");
if ( touchView ) {
[touchView touchesCancelled:[event allTouches] withEvent:event];
touchView = nil;
}
}
else if (touch.phase == UITouchPhaseEnded) {
NSLog(@"TouchCapturingWindow --> TouchPhaseEnded");
if ( touchView ) {
[touchView touchesEnded:[event allTouches] withEvent:event];
touchView = nil;
}
}
//we need to send the message to the super for the
//text overlay to work (holding touch to show copy/paste)
[super sendEvent:event];
}
@end
Viewer.h :
@interface Viewer : UIViewController{
int currentPage;
int totalPages;
IBOutlet UIView *pagesView;
int lastTchX;
int difference;
BOOL hasMoved;
int touchBeganSeritX;
}
- (IBAction)backBtnClicked:(id)sender;
- (void)loadImages;
- (void)animationDidStop;
- (void)loadSinglePage:(int)pageNo;
@property (nonatomic, retain) IBOutlet UIView *pagesView;
@end
Viewer.m :
@interface Viewer ()
@end
@implementation Viewer
@synthesize pagesView;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
}
- (IBAction)backBtnClicked:(id)sender
{
[self.navigationController popViewControllerAnimated:YES];
}
- (void)loadImages
{
for(UIView *subView in pagesView.subviews)
{
[subView removeFromSuperview];
}
currentPage = 1;
totalPages = 12;
for(int count = 1; count <= 12; count++)
{
[self loadSinglePage:count];
}
}
- (void)loadSinglePage:(int)pageNo
{
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory , NSUserDomainMask, YES);
NSString *cachesDir = [paths objectAtIndex:0];
NSString *pagesDir = [NSString stringWithFormat:@"%@/pages", cachesDir];
int pageX = (pageNo - 1) * 768;
UIWebView *aPageWebView = [[UIWebView alloc] init];
[aPageWebView setFrame:CGRectMake(pageX, 0, 768, 1024)];
aPageWebView.backgroundColor = [UIColor clearColor];
aPageWebView.opaque = YES;
[aPageWebView setClearsContextBeforeDrawing:YES];
aPageWebView.clipsToBounds = NO;
[aPageWebView setScalesPageToFit:YES];
NSString *hamData = [NSString stringWithFormat:@"<!DOCTYPE html><html><head><meta charset=\"UTF-8\"><meta name=\"viewport\" content=\"user-scalable=yes, width=1024, height=1365, maximum-scale=1.0\"><style type=\"text/css\">body {margin:0; padding:0;}</style></head><body bgcolor=\"#508CCF\"><div id=\"touchable\" style=\"top:0px; left:0px; width:1024px; height:1365px; background-image:url(%@.jpg)\"></div></body></html>", [[NSNumber numberWithInt:pageNo] stringValue]];
[aPageWebView loadHTMLString:hamData baseURL:[NSURL fileURLWithPath:pagesDir isDirectory:YES]];
aPageWebView.scrollView.bounces = NO;
[aPageWebView.scrollView setMaximumZoomScale:1.3333f];
[aPageWebView.scrollView setMinimumZoomScale:1.0f];
aPageWebView.scrollView.zoomScale = 1.0f;
[aPageWebView setMultipleTouchEnabled:YES];
[pagesView addSubview:aPageWebView];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(@"touchesBegan");
UITouch *myTouch = [[event allTouches] anyObject];
int curTchX = [myTouch locationInView:self.view].x;
lastTchX = curTchX;
hasMoved = NO;
touchBeganSeritX = pagesView.frame.origin.x;
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(@"Viewer : .....moved");
hasMoved = YES;
UITouch *myTouch = [[event allTouches] anyObject];
int curTchX = [myTouch locationInView:self.view].x;
difference = curTchX - lastTchX;
int newX = (pagesView.frame.origin.x + difference);
if(newX <= 0)
{
[pagesView setFrame:CGRectMake((pagesView.frame.origin.x + difference), 0, pagesView.frame.size.width, 1024)];
}
lastTchX = curTchX;
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(@"touchesEnded");
if(hasMoved == YES)
{
hasMoved = NO;
int curSeritX = pagesView.frame.origin.x;
curSeritX = curSeritX / (-1);
int newX = 0;
if(difference < 0) //Sağa geçilecek
{
if((currentPage + 1) <= totalPages)
{
currentPage++;
}
}
else //Sola geçilecek
{
if((currentPage - 1) >= 1)
{
currentPage--;
}
}
newX = (currentPage - 1)*768*(-1);
[UIView animateWithDuration:0.2f
delay:0.0f
options:UIViewAnimationOptionCurveEaseOut
animations:^{
// Do your animations here.
[pagesView setFrame:CGRectMake(newX, 0, pagesView.frame.size.width, pagesView.frame.size.height)];
}
completion:^(BOOL finished){
if (finished) {
// Do your method here after your animation.
}
}];
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(@"touchesCancelled");
}
- (void)viewDidUnload
{
[super viewDidUnload];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return YES;
}
@end
