I am currently coding an educational game in which I need the background to be continuously moving. I've tried to use blocks (iOS 4), for some reason the result isn't satisfying (even if I specify a linear animation, the image slows down at the end. Any suggestion? Thanks for your help!
soil0 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"soil900.jpg"]];
soil0.frame = CGRectMake(0, 0, [UIScreen mainScreen].applicationFrame.size.width, [UIScreen mainScreen].applicationFrame.size.height);
[UIView animateWithDuration:5.0
delay:0.0
options:UIViewAnimationOptionRepeat | UIViewAnimationCurveLinear
animations:^{
soil0.transform = CGAffineTransformMakeTranslation(0, -450); }
completion:^(BOOL fin) { if (fin)
{
soil0.transform = CGAffineTransformMakeTranslation(0, +450);
}
}];
I think perhaps you are seeing easing. UIViewAnimationCurveLinear is for use with the setAnimationCurve class method. Try using UIViewAnimationOptionCurveLinear instead.
Related
I'm looking for a way to add a multiline UITextView to an UIAlertView. I googled a lot, but I couldn't find a working solution.
I'm using iOS 5.
Or is that only possible with a subclass of UIAlertView?
EDIT: I need a multiple-line input.
Editing UIAlertViews is flagged as bad practice by apple. So its probably best to create your own custom UIViewController which looks like an alert view.
Make it so that instead of your function calling an alert, it loads your new View controller
This is a good example of an animation for your UIViewController to make it act like a typical IOS AlertView
-(void)initialDelayEnded {
self.view.transform = CGAffineTransformScale(CGAffineTransformIdentity, 0.001, 0.001);
self.view.alpha = 1.0;
[UIView animateWithDuration:kTransitionDuration/1.5 animations:^{
self.view.transform = CGAffineTransformScale(CGAffineTransformIdentity, 1.1, 1.1);
}completion:^(BOOL complete){
[UIView animateWithDuration:kTransitionDuration/2 animations:^{
self.view.transform = CGAffineTransformScale(CGAffineTransformIdentity, 0.9, 0.9);
}completion:^(BOOL complete){
[UIView animateWithDuration:kTransitionDuration/2 animations:^{
self.view.transform = CGAffineTransformIdentity;
}];
}];
}];
}
I'm attempting to fade in a UIView that I've created by animating the alpha. I need to fade it in, leave it visible for a few seconds, then fade it out.
The fade out function works fine. The view smoothly disappears. But the fade in just makes the view appear instantly instead of slowly appearing over an interval of 0.5 seconds.
So it seems like the fade in animation isn't working, just instantly setting the alpha to 1.0. I'm kind of at a loss here. Any ideas what I'm doing wrong? Thanks!
-(void)presentPopupPhrase:(NSString *)phrase
inView:(UIView *)view
withDelegate:(id)delegate
andCompletion:(void (^)(BOOL completed))completion {
MessagePopupView *pv = [[[MessagePopupView alloc] initWithFrame:self.frame andText:phrase] autorelease];
pv.alpha = 0.0;
[view addSubview:pv];
[self fadeInMPV:pv
withDuration:self.fadeDuration
andDelay:self.fadeInDelay];
[self fadeOutMPV:pv
withDuration:self.fadeDuration
afterDelay:self.fadeOutDelay
withCompletion:completion
andDelegate:delegate];
}
-(void)fadeInMPV:(MessagePopupView *)mpv
withDuration:(NSTimeInterval)duration
andDelay:(NSTimeInterval)delay
{
[UIView animateWithDuration:duration
delay:delay
options:UIViewAnimationOptionCurveLinear
animations:^{
mpv.alpha = 1.0;
}
completion:nil];
}
-(void)fadeOutMPV:(MessagePopupView *)mpv
withDuration:(NSTimeInterval)duration
afterDelay:(NSTimeInterval)delay
withCompletion:(void (^)(BOOL completed))completion
andDelegate:(id)delegate
{
[UIView animateWithDuration:duration
delay:delay
options:UIViewAnimationOptionCurveLinear
animations:^{
mpv.alpha = 0.0;
}
completion:completion];
}
EDIT:
If it helps, here's the VC code where I'm calling it from:
-(void)viewDidAppear:(BOOL)animated {
CGRect phraseFrame = CGRectMake(20, 341, 280, 65);
PopupPhraseController *phraseController = [[[PopupPhraseController alloc] initWithFrame:phraseFrame] autorelease];
[phraseController presentPopupPhrase:#"Test Phrase" inView:self.view withDelegate:self andCompletion:^(BOOL completed){
if (completed) {
NSLog(#"completed");
} else {
NSLog(#"not completed");
}
NSLog(#"blocked!");
}];
[super viewDidAppear:animated];
}
You can't chain the animations like that as the second animation block essentially causes the first one to be cancelled out.
You have two options for Linking Multiple Animations Together:
Use the completion handler of the first animation
Nest the animations but delay the second one
Looks something like this
[UIView animateWithDuration:self.fadeDuration
delay:self.fadeInDelay
options:UIViewAnimationOptionCurveLinear
animations:^{
pv.alpha = 1.0;
} completion:^(BOOL finished) {
[UIView animateWithDuration:self.fadeDuration
delay:self.fadeOutDelay
options:UIViewAnimationOptionCurveLinear
animations:^{
pv.alpha = 0.0;
} completion:completion];
}];
Looks something like this
[UIView animateWithDuration:self.fadeDuration
delay:self.fadeInDelay
options:UIViewAnimationOptionCurveLinear
animations:^{
pv.alpha = 1.0;
[UIView animateWithDuration:self.fadeDuration
delay:self.fadeOutDelay + self.fadeDuration
options:UIViewAnimationOptionCurveLinear
animations:^{
pv.alpha = 0.0;
} completion:completion];
} completion:nil];
The issue is because of the way you are setting up the animations.
When you set animatable properties on a view the backing model of the view is updated instantly. So when you set the alpha = 1.0 in the first block the backing data model for the view has the alpha as 1.0 and then the actual animation is kicked off on another thread to show the interpolation between the two values.
When you define the second block straight after the first the view essentially says "ok I need to animate from 1.0 (my current value in the model) to 0.0", which is why you don't see what you expected.
Thanks to Paul.s for dropping the hint there. I think this expected behaviour is a little weird, even if it seems logical from a low level perspective.
To expand on Paul's 2 solutions, there is a 3rd solution which is better IMO.
Use GCD to add a delay to the fade out code, like such:
//Make sure this delay exceeds your fade-in time...
double delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
[self fadeOutMPV:pv
withDuration:self.fadeDuration
afterDelay:self.fadeOutDelay
withCompletion:completion
andDelegate:delegate];
});
This solution's better because the executing view controller has complete control on not only when, but what gets to trigger the fade out (for example, a user action).
We are trying to do a dissolve between two almost exact images (almost animation frames) but so far we cannot remove the darkening that happens midway through the dissolve. The client is very firm about not having this darker dissolve, anything thought?
UIImageView *newImageView = [[UIImageView alloc] initWithFrame:imageViewSmileDesign.frame];
newImageView.image = imageViewSmileDesign.image;
[self.view addSubview:newImageView];
imageViewSmileDesign.image = [UIImage imageNamed:[NSString stringWithFormat:#"%#.jpg", result]];
imageViewSmileDesign.alpha = 0;
[UIView animateWithDuration:0.5 animations:^{
imageViewSmileDesign.alpha = 1;
newImageView.alpha = 0;
} completion:^(BOOL finished) {
[newImageView removeFromSuperview];
} ];
Thanks for looking.
You could use the cross-disolve animation that's built into UIView:
+ (void)transitionFromView:(UIView *)fromView toView:(UIView *)toView duration:(NSTimeInterval)duration options:(UIViewAnimationOptions)options completion:(void (^)(BOOL finished))completion
Set options to UIViewAnimationOptionTransitionCrossDissolve.
Just don't change the alpha of 'newImageView' to 0. This will cause the new image to fade on top of the old one, and you don't have this half-way state where they are both semi-transparent revealing the background color.
You will have to bring imageViewSmileDesign to the front with a call to bringSubviewToFront: before the animation.
If both images have the same frame, just remove newImageView.alpha = 0;. That'll do the trick.
You need to delay the START of the newImageView.alpha fade.
In iOS, how can one briefly draw attention to an object on screen? Suppose, create a brief glow or cause a shadow to appear and then disappear?
For the purposes of this question, let's define "object on screen" as an instance of UIImageView.
Also, if possible provide an example of how to draw attention to a button.
Most people list code, but I'm sticking to describing some examples;
I've seen objects briefly grow and shrink back to their normal size to draw attention
Bejeweled (a Popcap game) lets diamonds briefly 'shine' (as if sunlight passed over it) to give you a subtle hint
I've seen certain applications use a hand or a fictive character point to a certain object briefly
And of course, you could always introduce a talking paperclip to tell you what's what.
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.1f];
yourView.transform = CGAffineTransformMakeScale(1.1, 1.1);
[UIView commitAnimations];
Or, of course the same thing with a block animations. And after the attention got away from your view you can use :
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.1f];
yourView.transform = CGAffineTransformIdentity;
[UIView commitAnimations];
Here is a simple hop animation...
- (void)drawAttn
{
float jumpHeight = 20.0;
CGPoint originalPoint = objectForAttn.center;
CGPoint jumpPoint = CGPointMake(objectForAttn.center.x, objectForAttn.center.y - jumpHeight);
[UIView animateWithDuration:0.20 delay:0.0 options:UIViewAnimationOptionAutoreverse animations:^{
[objectForAttn setCenter:jumpPoint];
} completion:^(BOOL finished) {
/* do other stuff after hop */
}];
}
My app QCount (free in the store, tap a "wrong" number 3 times) uses a fade animation as follows:
(note I wrote this when I was REALLY new to iOS, so there is probably a more compact way to write it)
aLabel = // a UILabel I get from somewhere
aColor = aLabel.backgroundColor;
[UIView animateWithDuration:0.2
delay: 0.0
options: UIViewAnimationOptionCurveEaseOut
animations:^{
aLabel.alpha = 0.0;
}
completion:^(BOOL finished){
// Wait .2 seconds and then fade in the view
[UIView animateWithDuration:.2
delay: 0.0
options:UIViewAnimationOptionCurveEaseIn
animations:^{
aLabel.alpha = 1.0;
}
completion:nil];
}];
There are lots of options: hopping, underlining, vibrating, blinking, rotating, scaling, endarkening around, and their combinations.
But IMO, shine effect on "slide to unlock" text is excellent.
You can check it out here:
iPhone "slide to unlock" animation
I wanted to draw attention to a label whose value had changed. This simple animation produces a nice 'I've changed' animation...
//copy the label
UILabel *newPageLabel = [[UILabel alloc] initWithFrame:_countLabel.frame];
[newPageLabel setFrame:CGRectOffset(newPageLabel.frame, 0, 0)];
newPageLabel.text = _countLabel.text;
newPageLabel.textAlignment = _countLabel.textAlignment;
newPageLabel.backgroundColor = _countLabel.backgroundColor;
newPageLabel.textColor = _countLabel.textColor;
newPageLabel.font = _countLabel.font;
//scale and fade out the copied label
[self.navigationController.toolbar addSubview:newPageLabel];
[UIView animateWithDuration:0.5
delay:0.0
options:UIViewAnimationOptionLayoutSubviews
animations:^{
newPageLabel.transform = CGAffineTransformMakeScale(2,2);
newPageLabel.alpha = 0;
}
completion:^(BOOL finished){
[newPageLabel removeFromSuperview];
}
];
I need to show 2 bar graphs in my app, I dont want to use core-plot as is overkill to show just 2 bars with variant height, [UIimageView with box.png]
i have done some tests just using UIView animations, wich seem to be enough to make the bar grow or shrink, [the problem is that the height is dependant on the starting point, so my bar doesnt have a point 0 for Y, wich changes with the height for the bar]
so how could i set a point 0 for my Y axis?, so I just have to think of heigh, and not the starting point as well?
or shall i go with some bar generator framework that is not so over kill as core-plot,,
what is the simplest, lightest weight?
power-plot
ecgraph, Other?
PS. the other point is that i need to have a custom background for the chart, and custom bars thats why im using box.png for the bars]
the code...
viewDidLoad { ***
CGRect chartbackGroundImageRect = CGRectMake(150, 20, 632, 653);
UIImageView *chartbackGroundImage = [[UIImageView alloc] initWithFrame:chartbackGroundImageRect];
[chartbackGroundImage setImage:[UIImage imageNamed:#"chartArtBgnd.png"]];
chartbackGroundImage.opaque = YES; // explicitly opaque for performance
[self.view addSubview:chartbackGroundImage];
[chartbackGroundImage release];
CGRect leftBarImageRect = CGRectMake(550, 550, 81, 40);
leftBarImage = [[UIImageView alloc] initWithFrame:leftBarImageRect];
[leftBarImage setImage:[UIImage imageNamed:#"leftBar.png"]];
leftBarImage.opaque = YES; // explicitly opaque for performance
[self.view addSubview:leftBarImage];
[leftBarImage release];
***}
testBarAnimation {***
// Setup the animation
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:0.2]; //animation for arrow
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
[UIView setAnimationBeginsFromCurrentState:YES];
CGRect newFrame = CGRectMake(550, 300, 81, 290);
leftBarImage.frame = newFrame;
[UIView commitAnimations];
***}
thanks a lot!
Define a utility function:
CGRect modifyRectByHeight(CGRect originalRect, CGFloat newHeight)
{
CGRect result = originalRect;
result.origin.y += height;
result.size.height += height;
return result;
}
Then use as follows:
leftBarImage.frame = modifyRectByHeight( leftBarImage.frame, 150);
I dont know, it's applicable to your project. But I used different approach, as iOS doesn't have good libraries for Chart.
I used UIWebview with HTML5 /CSS based free chart engines available on Web. For me its working fine, Bit slow than native charts would be but enough for my project