iOS Unit Testing with Animations - ios

Why does the following unit test pass using Xcode 5.0 and XCTesting? I mean, I understand the bottom line: 1 == 0 is not evaluated. But why is it not evaluated? How can I make this perform so that it would fail?
- (void)testAnimationResult
{
[UIView animateWithDuration:1.5 animations:^{
// Some animation
} completion:^(BOOL finished) {
XCTAssertTrue(1 == 0, #"Error: 1 does not equal 0, of course!");
}];
}

This will, technically, work. But of course the test will sit and run for 2 seconds. If you have a few thousand tests, this can add up.
More effective is to stub out the UIView static method in a category so that it takes effect immediately. Then include that file in your test target (but not your app target) so that the category is compiled into your tests only. We use:
#import "UIView+Spec.h"
#implementation UIView (Spec)
#pragma mark - Animation
+ (void)animateWithDuration:(NSTimeInterval)duration animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion {
if (animations) {
animations();
}
if (completion) {
completion(YES);
}
}
#end
The above simply executes the animation block immediately, and the completion block immediately if it's provided as well.

Better approach (right now) is to use expectation.
func testAnimationResult() {
let exp = expectation(description: "Wait for animation")
UIView.animate(withDuration: 0.5, animations: {
// Some animation
}) { finished in
XCTAssertTrue(1 == 0)
exp.fulfill()
}
waitForExpectations(timeout: 1.0, handler: nil)
}

#dasblinkenlight was on the right track; this is what I did to make it work correctly:
- (void)testAnimationResult
{
[UIView animateWithDuration:1.5 animations:^{
// Some animation
} completion:^(BOOL finished) {
XCTAssertTrue(1 == 0, #"Error: 1 does not equal 0, of course!");
}];
[[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:2.0]];
}

The goal here is to convert an asynchronous operation into a synchronous operation. The most general way to do this is with a semaphore.
- (void)testAnimationResult {
// Create a semaphore object
dispatch_semaphore_t sem = dispatch_semaphore_create(0);
[UIView animateWithDuration:1.5 animations:^{
// Some animation
} completion:^(BOOL finished) {
// Signal the operation is complete
dispatch_semaphore_signal(sem);
}];
// Wait for the operation to complete, but not forever
double delayInSeconds = 5.0; // How long until it's too long?
dispatch_time_t timeout = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
long timeoutResult = dispatch_semaphore_wait(sem, timeout);
// Perform any tests (these could also go in the completion block,
// but it's usually clearer to put them here.
XCTAssertTrue(timeoutResult == 0, #"Semaphore timed out without completing.");
XCTAssertTrue(1 == 0, #"Error: 1 does not equal 0, of course!");
}
If you want to see some examples of this in action, look at RNCryptorTests.

Related

Why are completion handlers of [UIView animate] called in a wrong order?

In my project there's a ViewController which contains a few subviews(e.g. buttons).
It shows/hides those buttons, always with animation.
It has an interface like this:
#interface MyViewController: UIViewController
- (void)setMyButtonsVisible:(BOOL)visible;
#end
And an implementation looks like this:
- (void)setMyButtonsVisible:(BOOL)visible
{
if( visible )
{
// "show"
_btn1.hidden = NO;
_btn2.hidden = NO;
[UIView animateWithDuration:0.2 animations:^{
_btn1.alpha = 1.0;
_btn2.alpha = 1.0;
}];
}
else
{
// "hide"
[UIView animateWithDuration:0.2 animations:^{
_btn1.alpha = 0.0;
_btn2.alpha = 0.0;
} completion:^(BOOL finished) {
_btn1.hidden = YES;
_btn2.hidden = YES;
}];
}
}
When [_myVC setMyButtonsVisible:NO] is called, and then after some time ( > 0.2s) [_myVC setMyButtonsVisible:YES] is called, everything is OK.
However, it setMyButtonsVisible:YES is called immediately after ( < 0.2s) setMyButtonsVisible:NO, the animations overlap and setMyButtonsVisible:NO callback is called the last.
I've tried to change "hide" duration to 0.1, it doesn't help - after "hide(0.1)"+"show(0.2)" calls, "hide" callback is called after the "show" callback and my buttons are not visible.
I've added a quick-fix by caching the visible param and checking in "hide" completion handler if the state should be !visible.
My questions are:
Why the first animation completion handler is called the last if animations overlap?
What are better approahes to discard a previous "overlapping" animation?
Check the finished flag on completion:
if (finished) {
_btn1.hidden = YES;
_btn2.hidden = YES;
}

Pausing an animation in iOS (objective C)

I am having some trouble handling animations in some objective C code.
First, here is the relevant code:
BOOL pauseFlag; // Instance variable.
CGFloat animationDuration,pauseDuration; // Instance variables.
......
pauseFlag = NO;
animationDuration = 1.0;
pauseDuration = 1.0;
- (void)animationFunction
{
[UIView animateWithDuration:animationDuration
delay:pauseFlag?pauseDuration:0
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
......
}
completion:^(BOOL finished){
......
pauseFlag = Some_New_Value;
[self animationFunction];
}];
}
Then here is the problem:
The delay supposed to take place when pauseFlag is YES is not happening.
Of course, before writing this post I have tried various solutions which came up to my mind, like changing the options, and I also checked that when entering animationFunction pauseFlag had the value YES. But in all cases the delay was ignored.
What did I do wrong? I need to insert a pause in my animation and thought this was the simplest way to do it.
Anyone has an idea?
Just for information, beside this issue. This animation code is working fine.
Try to animate your view with UIViewPropertyAnimator:
UIViewPropertyAnimator* animator = [UIViewPropertyAnimator runningPropertyAnimatorWithDuration:animationDuration
delay:pauseFlag?pauseDuration:0
options:UIViewAnimationOptionBeginFromCurrentState
animations:^{
......
}
completion:^(UIViewAnimatingPosition finalPosition) {
......
pauseFlag = Some_New_Value;
[self animationFunction];
}];
If you want to pause the animation call pauseAnimation:
[animator pauseAnimation];
To resume it call startAnimation:
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[animator startAnimation];
});
All code in this post was tested in Xcode 10.2.1.

iOS show recursive loading animation until completion of initialisation code block, then show the last animation

I want to show loading animation while I am doing some initialisation. So I want to spin my (UIImageView*)_LogoImage until my initialisation will be completed. Then, after initialisation will be finished, I want to scale my _LogoImage. So, all this things begins from viewDidAppear, where I am calling beginLoading: method.
-(void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
[self beginLoading];
}
Here, I am starting my spin animation. Assume, I am doing some initialisation in the next two code lines, I changed them to make a thread sleep to make a similar behaviour of my initialisation code. Then I am calling stopSpin: method to make the next half circle and to do my last scaling animation.
-(void)beginLoading{
[self startSpin];
[self sleepAction:3.0f];
[self sleepAction:1.0f];
[self stopSpin];
}
-(void)sleepAction:(float)sleepTime{
NSLog(#"SleepTime:[%f]",sleepTime);
[NSThread sleepForTimeInterval:sleepTime];
}
Here's my spinning code, which I am calling recursively until my BOOL refreshAnimating is Equal to YES. if not - running the last scaling animation
-(void)startSpin{
[UIView animateWithDuration:0.4
delay:0
options:UIViewAnimationOptionCurveLinear
animations:^{
_LogoImage.transform = CGAffineTransformMakeRotation(M_PI);
}
completion:^(BOOL finished){
[UIView animateWithDuration:0.4
delay:0
options:UIViewAnimationOptionCurveLinear
animations:^{
_LogoImage.transform = CGAffineTransformMakeRotation(0);
}
completion:^(BOOL finished){
if (refreshAnimating) {
[self startSpin];
}else{
[self refreshFinished];
}
}];
}];
}
-(void)stopSpin{
refreshAnimating = NO;
}
-(void)refreshFinished{
[UIView animateWithDuration:0.4 animations:^{
[_LogoImage setTransform:CGAffineTransformMakeScale(2, 2)];
}];
}
The problem is that my animation is not running, until the last initialisation code line completes. And after completion - I can see only the last animation. I was trying to put some code performing in the background and main thread, but I didn't run the way I want.
The rotation animation should start when the view appears, and continue until my initialisation code complete - then I want to see my last scale animation, which will indicate that my initialisation is completed.
Please, help.
All animations run on main thread and if you use sleep, it blocks your animations(main thread). Instead you can use a library like: MBProgressHUD please feel free to ask further questions.
Edit
-(void)startSpin{
_LogoImage.transform = CGAffineTransformMakeRotation(M_PI);
[UIView animateWithDuration:0.4
delay:0
options:UIViewAnimationOptionCurveLinear
animations:^{
_LogoImage.transform =CGAffineTransformMakeRotation(0);
}
completion:nil];
}
Can you try this. I think that is what are trying to do.
As #Ersin Sezgin said, all animations run on main thread.
So now, I am doing initialisation in background with completion block handler, which is forcing stopSpin: after initialisation completes.
Here's some code block. For better readability there's typedef of block.
typedef void(^OperationSuccessCompletionHandler)(BOOL success);
in .m file
-(void)sleepAction:(OperationSuccessCompletionHandler)success{
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
// We are doing initialisation here
BOOL isOperationSuccess = YES // Assume initialisation was successful
success(isOperationSuccess);
});
}
So now we can do this in another way
-(void)beginLoading{
[self startSpin];
[self sleepAction:^(BOOL success){
[self sleepAction:^(BOOL success){
[self stopSpin];
}];
}];
}

Animation freezes when processing JSON

I have a custom animation wich i am calling with this method:
- (void)spinWithOptions:(UIViewAnimationOptions)options directionForward:(BOOL)directionForward {
[UIView animateWithDuration:0.3
delay:0.0
options:options
animations:^{
CATransform3D transform;
if (!directionForward) {
transform = CATransform3DIdentity;
} else {
transform = CATransform3DIdentity;
transform.m34 = -1.0 / 500.0;
transform = CATransform3DRotate(transform, M_PI - 0.0001f /*full rotation*/, 0, 1, 0.0f);
}
self.logoImageView.layer.transform = transform;
} completion:^(BOOL finished) {
if (!_animating && options != UIViewAnimationOptionCurveEaseOut) {
[self spinWithOptions:UIViewAnimationOptionCurveEaseOut directionForward:NO];
} else if (options == UIViewAnimationOptionCurveLinear) {
[self spinWithOptions:UIViewAnimationOptionCurveLinear directionForward:!directionForward];
} else {
// animation finished
}
}];
}
but I have a problem, when the animation runs and I do some processing from a server with AFNetworking and CoreData the animation freezes, i think the main thread is blocked but I also have a MBProgresHUD and that doesn't freeze. Any idea how i can make this animation not freeze?
you do the animation and all the networking on the same thread. only one thing can run on one thread at a time though so your loading blocks the animation.
you need to offload tasks so the thread can run just one thing. ANY ui modification needs to happen on the main thread, so we offload the networking.
- startMyLongMethod {
[self startAnimation]; //your spin thingy
//get a background thread from GCD and do the work there
dispatch_async(dispatch_get_global_queue(0,0), ^{
//do longRunning op (afnetwork and json parsing!)
id result = [self doWork];
//go back to the main thread and stop the animation
dispatch_async(dispatch_get_main_queue(), ^{
[self updateUI:result];
[self stopAnimation];//your spin thingy
});
});
}
note: example code and written inline! The approach should be clear now though

How to wait until code is done. iOS

I can call some selector by this code
[self performSelector:<#(SEL)#> onThread:<#(NSThread *)#> withObject:<#(id)#> waitUntilDone:<#(BOOL)#>]
and the Thread will wait until this selector is working (if I set waitUntilDone:YES). My question is - Can i wait until some code is done?
for example. I have some subview, which loads with animation. Animation duration is 2 sec. And if i make some actions on background view, while animating, i have an error. I'd like to wait until animation is over. And I can't to make a selector, and use
[self performSelector:<#(SEL)#> onThread:<#(NSThread *)#> withObject:<#(id)#> waitUntilDone:<#(BOOL)#>]
Any suggestions? )
You can try this way
-(void)waitUntilDone:(void(^)(void))waitBlock {
//use your statement or call method here
if(waitBlock){
waitBlock();
}
}
And you need to use it as
[self.tableView waitUntilDone:^{
//call the required method here
}];
UIView animation gives this to you in the form of the block style animation
[UIView animateWithDuration:0.25f
animations:^{
// animations
} completion:^(BOOL finished) {
// run code when the animation is finished
}];
Wait until animation gets finished & then do rest of the things :
For eg:
[UIView animateWithDuration:duration
animations:^
{
//DO ANIMATION ADJUSTMENTS HERE
}
completion:^(BOOL finished)
{
//ANIMATION DID FINISH -- DO YOUR STUFF
}];

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