I found this code to change the image when it is clicked.
in .h
#interface MyappViewController : UIViewController
{
NSDictionary *ddata;
UIImageView *firstImage;
}
#property(retain,nonatomic) IBOutlet UIImageView *firstImage;
in .m
- (void)viewDidLoad
{
[super viewDidLoad];
firstImage.userInteractionEnabled = YES;
UIPinchGestureRecognizer *pgr = [[UIPinchGestureRecognizer alloc]
initWithTarget:self action:#selector(clickHandler:)];
pgr.delegate = self;
[firstImage addGestureRecognizer:pgr];
[pgr release];
// [self clickHandler:self];
}
-(void)animationDidStop:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context {
/* destroy the transition view, set the image first */
UIImageView *transitionImageView = (UIImageView *)context;
self.firstImage.image = transitionImageView.image;
[transitionImageView removeFromSuperview];
transitionImageView = nil;
}
- (void)clickHandler:(id)sender {
/* temporary view for the animation */
NSLog(#"Click Handled ");
UIImageView *transitionImageView = [[UIImageView alloc] initWithFrame:self.firstImage.frame];
UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[ddata objectForKey:#"pic"]]]];
transitionImageView.image = image;
transitionImageView.alpha = 0.0f;
[self.view addSubview:transitionImageView];
[UIView beginAnimations:#"UpdateImages" context:transitionImageView];
[UIView setAnimationDuration:2.0f];
transitionImageView.alpha = 1.0f;
[UIView setAnimationDidStopSelector:#selector(animationDidStop:finished:context:)];
[UIView commitAnimations];
}
When I click the image nothing happens, but if I call [self clickHandler:self]; in ViewDidLoad, the image changes. My problem is that the click is not handled when I click the image.
Instead of a UIPinchGestureRecognizer you need to use a UITapGestureRecognizer. Don't forget to set things like the number of taps required and number of fingers either. The docs are very good for gesture recognizers.
Related
For a exercise I created a project to experiment with the accelerometer functions of the iPhone. Right now when I run the app on my device it begins with a blank screen, shake the phone and a image is displayed.
I have to force close the app to clear the image. I was hoping someone could provide a solution that would make the image reset so I could repeat the process as many times as I wanted. (shake phone, display image, clear image) I'm thinking it needs a timer or something, not sure. Here is the source code. Thanks for taking the time to read and help.
// ViewController.m
// AccelTest
//
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)viewDidUnload
{
[super viewDidUnload];
}
-(void)viewWillAppear:(BOOL)animated{
[self startAccel];
[self view];
}
-(void)viewWillDisappear:(BOOL)animated{
[self stopAccel];
[self view];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return NO;
}
-(void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration{
double const kThreshold = 2.0;
// double const kThreshold = 2.0;
if ( fabsf(acceleration.x) > kThreshold
|| fabsf(acceleration.y) > kThreshold
|| fabsf(acceleration.z) > kThreshold){
[self.view addSubview:[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"Icon.png"]]];
}
}
-(void)startAccel{
UIAccelerometer * accel = [UIAccelerometer sharedAccelerometer];
accel.delegate = self;
accel.updateInterval = .25;
}
-(void)stopAccel{
UIAccelerometer * accel = [UIAccelerometer sharedAccelerometer];
accel.delegate = nil;
}
#end
Here is how I would do it (without ARC) to tap the image to make it disappear.
Remove your line:
[self.view addSubview:[[UIImageView alloc]initWithImage:[UIImage imageNamed:#"Icon.png"]]];
And add these lines instead:
UIImageView *myImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"Icon.png"]];
myImageView.userInteractionEnabled = YES;
UITapGestureRecognizer *tapgr = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(rm:)];
[myImageView addGestureRecognizer:tapgr];
[tapgr release]; tapgr = nil;
[self.view addSubview:myImageView];
[myImageView release]; myImageView = nil;
Then add a method to the View Controller to remove the UIImageView when it is tapped.
-(void)rm:(UITapGestureRecognizer *)tapgr {
[tapgr.view removeFromSuperview];
}
When that Image is tapped once, the rm: method will be called which will remove the Image from self.view
Store a pointer to that image view somewhere and remove it from it's superview when you want to. Either with a timer, or user action, or something like that.
I have implemented UITapGestureRecognizer on UIImageView, It is working on first tap. On First Tap, I am hiding that image and starting animation. Once the animations are completed, i am showing the image again. But After setting setHidden:FALSE, I am not getting the Tap event of that UIImageView.
Following is the code I am using :
- (void)viewDidLoad{
[super viewDidLoad];
defaultDogView= [[UIImageView alloc] initWithFrame:CGRectMake(3, 270, 110, 210)];
[defaultDogView setImage:[UIImage imageNamed:#"dog1.png"]];
defaultDogView.userInteractionEnabled = YES;
[self addGestureRecognizersToPiece:defaultDogView];
[self.view addSubview:defaultDogView];
}
- (void)addGestureRecognizersToPiece:(UIImageView *)piece
{
NSLog(#"in Gesture");
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(singleTapPiece:)];
[tapGesture setDelegate:self];
[piece addGestureRecognizer:tapGesture];
[tapGesture release];
UILongPressGestureRecognizer *longPressGesture = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(longPressPiece:)];
[piece addGestureRecognizer:longPressGesture];
[longPressGesture release];
NSLog(#"%#", [piece gestureRecognizers]);
}
- (void)singleTapPiece:(UITapGestureRecognizer *)gestureRecognizer
{
NSLog(#"Image Tapped");
/** Hide the default Image and start the animation ***/
[defaultDogView setHidden:TRUE];
/***Animating the Dog***/
[dogArray addObject:[SpriteHelpers setupAnimatedDog:self.view numFrames:69 withFilePrefix:#"dog" withDuration:(12) ofType:#"png" withValue:0]];
dogView = [dogArray objectAtIndex:0];
//[self addGestureRecognizersToPiece:dogView];
[self performSelector:#selector(callBubbleUpdater) withObject:nil afterDelay:5.5];
}
-(void)showDogFrame{
NSLog(#"%#",[defaultDogView gestureRecognizers]);
[defaultDogView setHidden:FALSE];
defaultDogView.userInteractionEnabled = YES;
}
When view is hidden or its alpha component is zero that view won't receive any UIGestureRecognizers.
I can suggest to use next approach if you need to hide some view (let's name it touchableView) but want it to respond to gestures:
Create backgroundView with the same frame as touchableView:
UIView *backgroundView = [[UIView alloc] initWithFrame:touchableView.frame];
Set background color of backgroundView to clearColor:
backgroundView.backgroundColor = [UIColor clearColor];
Reset position of touchableView:
CGRect frame = touchableView.frame;
frame.origin.x = 0;
frame.origin.y = 0;
Disable user interaction of touchableView:
touchableView.userInteractionEnabled = NO;
Add touchableView as subview to backgroundView:
[backgroundView addSubview:touchableView];
Add appropriate gesture recognizers to backgroundView.
Add backgroundView to view that you want.
Now you can hide touchableView but you will still receive gesture recognizers.
I don't test this but I think it should work.
sure
when UIImageView is hidden. it does not receive any touch events
set alpha zero for uiimageview
Hi I am trying to splash screen with the help of timer. but it can't. IS any suggestion regarding this code.........
SplashViewController.h:-
#import <UIKit/UIKit.h>
#import "MainMenu.h"
#interface SplashViewController : UIViewController {
UIImage *imgSplash;
NSTimer *timer;
MainMenu *objMainMenuView;
}
#property (nonatomic,retain) NSTimer *timer;
#property (nonatomic,retain) UIImage *imgSplash;
#property (nonatomic,retain) MainMenu *objMainMenuView;
#end
SplashViewController.m:-
#import "SplashViewController.h"
#implementation SplashViewController
#synthesize timer,imgSplash,objMainMenuView;
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
[super viewDidLoad];
timer = [[NSTimer alloc] init];
UIImageView *splashImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,320,460)];
imgSplash = [[UIImage alloc] init];
imgSplash = [UIImage imageNamed:#"chicocredit_splash.png"];
[splashImageView setImage:imgSplash];
[self.view addSubview:splashImageView];
timer = [NSTimer timerWithTimeInterval:2.0 target:self.timer selector:#selector(fadeScreen) userInfo:nil repeats:NO];
if([timer isValid]==1)
{
[timer fire];
//self.view.alpha = 0.0;
objMainMenuView = [[MainMenu alloc] initWithNibName:#"MainMenu" bundle:nil];
[self.navigationController pushViewController:objMainMenuView animated:YES];
}
}
-(void) onTimer{
NSLog(#"LOAD");
}
- (void)fadeScreen
{
[UIImageView beginAnimations:nil context:nil];
[UIImageView setAnimationDuration:2.0];
[UIImageView setAnimationDelegate:self];
[UIImageView commitAnimations];
//[UIView setAnimationDidStopSelector:#selector(finishedFading)];
//self.view.alpha = 0.0;
//[UIView commitAnimations];
}
/*
- (void) finishedFading
{
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:5.0];
//self.view.alpha = 1.0;
//viewController.view.alpha = 1.0;
//self.objMainMenuView.view.alpha = 1.0;
[UIView commitAnimations];
//[splashImageView removeFromSuperview];
}*/
- (void)dealloc {
[super dealloc];
}
#end
Use this It may be solution for that.
- (void)viewDidLoad {
timer = [[NSTimer alloc] init];
CGRect myImageRect = CGRectMake(0.0f, 0.0f, 320.0f, 460.0f);
splashImageView = [[UIImageView alloc] initWithFrame:myImageRect];
[splashImageView setImage:[UIImage imageNamed:#"image3.jpg"]];
splashImageView.opaque = YES;
[self.view addSubview:splashImageView];
[splashImageView release];
[self performSelector:#selector(doTHis) withObject:nil afterDelay:2.0];
[super viewDidLoad];
}
-(void)doTHis{
objMainMenuView = [[MainMenu alloc] initWithNibName:#"MainMenu" bundle:nil];
[self.navigationController pushViewController:objMainMenuView animated:YES];
}
Good Luck
Looks like your MianMenu is getting pushed before you can see the fade effect. Its because you are firing the timer and pushing the Main Menu immediately.
// Schedule the timer here.
[NSTimer timerWithTimeInterval:2.0f target:self selector:#selector(timerFireMethod:) userInfo:nil repeats:NO];
// Timer fire method.
-(void) timerFireMethod:(NSTimer *) theTimer {
[UIView beginAnimations:nil context: nil];
[UIView setAnimationDuration:2.0f];
[UIView setAnimationDelegate:self];
[UIView setAnimationDidStopSelector: #selector(animationDidStop: finished: context:)];
// Put animation code.
[UIView commitAnimations];
}
// Called when animation finishes.
-(void) animationDidStop:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context {
// Called when animation finishes.
// Push the Main menu here.
}
Keep break point in the timer fire method. It should get called after 2 seconds as specified.
Then keep break point in the animationDidStopSelector method. It will get called after your fade animation of 2 seconds.
Your code is leaked:
1:
timer = [[NSTimer alloc] init]; //Leak here, remove this line
.
.
.
timer = [NSTimer timerWithTimeInterval:2.0 target:self.timer selector:#selector(fadeScreen) userInfo:nil repeats:NO];
2:
imgSplash = [[UIImage alloc] init];//Leak here, remove this line
imgSplash = [UIImage imageNamed:#"chicocredit_splash.png"];
3:
UIImageView *splashImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,320,460)];
...
[splashImageView setImage:imgSplash]; //Leak here, should release splashImageView
Why not, do everything else after timer expired and fading is done.
- (void) finishedFading
{
objMainMenuView = [[MainMenu alloc] initWithNibName:#"MainMenu" bundle:nil];
[self.navigationController pushViewController:objMainMenuView animated:YES];
}
short cut: use another viewController with imageView present it modally and dismiss with animation dissolve.
You should present view in viewWillAppear.Start timer on viewLoad of second viewController.When timer fires dismiss it.
I have a scrollView where I add some UIButtons and UIActivityIndicators in the main thread.
Then I perform a [NSThread detachSelectorInBackground:#selector(getImages) toTarget:self withObject:nil];
getImages downloads some images and add them into UIImageViews and then adds the UIImageViews to the scrollView, but they wont show up until the method getImages is done.
Is there any way to get the scrollView to redraw or refresh or something like that?
AND
If I scroll the scrollView (with my fingers..) during the getImages method, the UIImageViews that has been added shows up.
- (void) getImages {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
int x=5;
int y=0;
NSData *imgData;
UIImage *img;
UIImageView *imgView;
for (NSDictionary *tmp in thumbs) {
imgData = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:[Functions urlForFile:[tmp objectForKey:#"img"]]]];
if ([imgData length] > 0) {
img = [[UIImage alloc] initWithData:imgData];
imgView = [[UIImageView alloc] initWithFrame:CGRectMake(x, y + (133-img.size.height)/2, 100, img.size.height)];
imgView.image = img;
[imgView setAlpha:0.0];
[[self.scrollView viewWithTag:1500000*[[tmp objectForKey:#"id"] intValue]] setAlpha:1.0];
[self.scrollView addSubview:imgView];
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:2.0];
[[self.scrollView viewWithTag:1500000*[[tmp objectForKey:#"id"] intValue]] setAlpha:0.0];
[imgView setAlpha:1.0];
[UIView commitAnimations];
[[self.scrollView viewWithTag:1500000*[[tmp objectForKey:#"id"] intValue]] removeFromSuperview];
[imgView release];
[img release];
[imgData release];
x+=105;
if (x > 300) {
x=5;
y+=138;
}
}
}
[pool release];
[appDelegate.loadingView setHidden:YES];
}
changing the UI in background is not thread-safe! Downloading in background but not displaying. To show an image one by one you can try to run it with performSelectorOnMainThread:#selector() withObject:nil waitUntilDone:YES
for example with self.scrollView addSubview:.
But again, UI should always use MainThread (e.g. animations)
I just want in my application a ticker,
i have no idea to implement ticker please tell me.
Thanks
Everything you need to do this is in the SDK, no need to customize at all. I haven't checked this, but you can try the following:
#import <UIKit/UIKit.h>
#interface TickerScrollView : UIScrollView {
UILabel *textLabel;
}
- (void)displayText:(NSString *)string;
- (void)clearTicker;
#property (nonatomic, retain, readwrite) UILabel *textLabel;
#end
////
#import "TickerScrollView.h"
#interface TickerScrollView()
- (void)initialiseTextLabel;
- (void)clearTicker;
- (void)beginAnimation;
#end
#implementation TickerScrollView
- (id)initWithFrame:(CGRect)frame {
if ((self = [super initWithFrame:frame])) {
// Initialization code
[self setFrame: frame];
[self setBounces: NO];
[self setUserInteractionEnabled:NO];
[self setShowsVerticalScrollIndicator:NO];
[self setShowsHorizontalScrollIndicator:NO];
[self initialiseTextLabel];
}
return self;
}
- (void)initialiseTextLabel {
textLabel = [[[UILabel alloc] initWithFrame:self.bounds] autorelease];
[textLabel setTextAlignment:UITextAlignmentLeft];
[textLabel setNumberOfLines:1];
[textLabel sizeToFit];
[self addSubview:textLabel];
[self sendSubviewToBack:textLabel];
[self setScrollEnabled:YES];
}
- (void)displayText:(NSString *)string {
[self clearTicker];
[textLabel setText:string];
[textLabel sizeToFit];
[self setContentSize:textLabel.frame.size];
[self beginAnimation];
}
- (void)clearTicker {
[textLabel setText:#""];
[textLabel sizeToFit];
CGPoint origin = CGPointMake(0, 0);
[self setContentOffset:origin];
}
- (void)beginAnimation {
CGFloat text_width = textLabel.frame.size.width;
CGFloat display_width = self.frame.size.width;
if ( text_width > display_width ) {
CGPoint origin = CGPointMake(0, 0);
[self setContentOffset:origin];
CGPoint terminal_origin = CGPointMake(textLabel.frame.size.width - self.frame.size.width, textLabel.frame.origin.y);
float duration = (text_width - display_width)/50;
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationCurve:UIViewAnimationCurveLinear];
[UIView setAnimationDelay:1.0];
[UIView setAnimationDuration:duration];
[self setContentOffset:terminal_origin];
[UIView commitAnimations];
}
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
// Drawing code
}
*/
- (void)dealloc {
[textLabel release];
[super dealloc];
}
#synthesize textLabel;
#end
Assuming by "Ticker" you mean a horizontally scrolling text:
A ticker is basically just a text string that is moving by having its x coordinate changed continuously. Check this simple tutorial on how to display a label:
http://knol.google.com/k/iphone-sdk-helloworld
Then later you can animate it by using an NSTimer to call a method updating the labels x coordinate continuously.