Use UIProgressView for image editing - iphone

In my app I apply filters for the image. I want to add UIProgressView as it takes about couple of seconds to complete the editing. How to add a UIProgressView for such method and also update how many percent it is completed? I have gone through many examples for UIProgressView but they are for Http request and loading network data. How to implement that for custom method ?

I guess you need to use Operation Queue for this.
[NSThread detachNewThreadSelector:#selector(showProgressView:) toTarget:self withObject:nil];
This has worked for me I hope it works for you too.. Have a happy Coding.!!

If you have control over how much of the editing is completed, like any delegate events you can update the progress just like network calls or others. Even if you don't have such events, you might be having some inner methods, which can give you a delta of the total progress happened.
Then you can have a method which takes in this delta, add it to existing progress.
- (void)updateProgress:(CGFloat)delta
{
[self.progressView setProgress:self.progressView.progress+delta];
self.progressLabel.text = [NSString stringWithFormat:#"Completed : %.0f",self.progressView.progress*100];
}

It's difficult to answer this without knowing what data you have available to you, but essentially, you need to have a method that gets called at a consistent periodic time interval until the image filter gets applied. A trick for doing this would be if you could come up with a time estimate for a filter and then just use an NSTimer to fire a method until that time is complete. Although if you could figure out an exact time for it to filter, that would obviously be preferable.
From there you need to set the progress of the progress view to that time over the amount of time total like so...
self.progressView.progress = (float) progress
Keep in mind though that the progress view is a percent, so you will need to store two values to compare (divide over each other) 1) the total amount of time 2) the total amount of time passed. You can just do this though by setting up a float progress in your user #interface.

Related

NSImageView update delayed when set from an NSTimer

I'm working on a project in Swift that requires strict control of image display and removal timings in certain sections. I'm finding that when I set the image property of an NSImageView from inside a block that's fired by a Timer, the actual display of the image on the screen is delayed by up to a second after the assignment is complete. (This is measured by eyeballing it and using a stopwatch to gauge the time between when an NSLog line is written and when the image actually appears on-screen.)
Triggering image display with a click appears to happen instantaneously, whether it's done by setting the image property of an existing NSImageView, or constructing one on the spot and adding it as a subview.
I have attempted to reduce the behavior down to a fairly simple test case, which, after basic setup of the view (loading the images into variables and laying out several target image locations, which are NSImageViews stored to the targets array), sets a Timer, with an index into the targets array stored in its userInfo property, to trigger the following method:
#objc func testATimer(fromTimer: Timer) {
if let targetLocation = fromTimer.userInfo as? Int {
NSLog("Placing target \(targetLocation)")
targets[targetLocation].image = targetImage
OperationQueue.main.addOperation {
let nextLocation = targetLocation + 1
if (nextLocation < self.targets.count) {
NSLog("Setting timer for target \(nextLocation)")
let _ = Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(ViewController.testATimer(fromTimer:)), userInfo: nextLocation, repeats: false)
}
}
}
}
The amount of time observed between the appearance of the log entry "Placing target x" and that of the image that is set to be displayed in the very next line seems to average between 0.3 and 0.6 seconds. This is far beyond the delay that this project can tolerate, as the image will only be on screen for a total of 1 second at a time.
My best guess as to why this is happening is that it is something to do with Timers running on a separate thread from the main display thread; however, I do not have enough experience with multi-threaded programming to know exactly how to mitigate that.
Any assistance would be most appreciated, and if I've left out information that would make answering easier (or possible) I'm more than happy to give it.
Well, after poking at it with some helpful people on in #macdev on irc.freenode.net, I found that the source of the problem was the program scaling the image down on the fly every time it set it to the NSImageView. Reducing the size of the image ahead of time solved the problem. (As did setting the image once, then hiding and showing the NSImageView instead.)

UIAutomation timeouts usage

Guys help me to understand the timeouts usage. The documentation gives quite a couple of words about them:
popTimeout- Retrieves the previous timeout value from a stack, restores it as the current timeout value, and returns it.
pushTimeout - Stores the current timeout value on a stack and sets a new timeout value.
They also provide some code:
target = UIATarget.localTarget();
target.pushTimeout(2);
// attempt element access
target.popTimeout();
But I don't exactly understand how and when to use them. Can anybode give an example?
During automation testing, some elements might not become visible right away. so instruments uses a timeout (default 5 seconds) to wait for requested elements. They call this the grace period.
Sometimes the default grace period might not be what you need, so you can change the timeout to a shorter or longer value.
Using the pushTimeout and popTimeout makes sure that the previous grace period is restored after calling popTimeout, without the need to remember the previous grace period.
For example: in one of my tests, I don't want to wait for a popover to become active, but I just want to know if there is a popover active, and dismiss it if there is:
target.pushTimeout(0.0);
if ( target.isDeviceiPad() && ! isNull( popOver= app.mainWindow().popover() ) )
{
UIALogger.logDebug(" dismiss popup by tapping somewhere");
popOver.dismiss();
target.delay(0.2);
}
target.popTimeout();
BTW, the isNull() is a custom function I made, but you probably understand what is going on.

NSMutableArray Difficulty

If you wanna see the code Im having problem with, here is the link:
Code
My question is connected with my past question.
I'm really having problem with my NSMutableArray, I'm currently using iCarousel for my slotMachine object(slot1 and slot2). My app works this way:
From PhotoViewController I made a view that has thumbnail images, then assign its frame with button. So if 1 image was pressed, it will save that integer via NSUserDefaults.
Then I will retrieve it in my carouselViewController
Im thinking of adjusting the array but I can't.
I also have tried my question here:
Comparing with NSMutableArray
If only I can do it the same as Array 2 it would be much easy, but still not working.
(ADDITIONAL INFO:)
I have done it this way, have a Viewcontroller that contains the UIImageView with a button in it, so when the user taps it, my CustomPicker pops up. My CustomPicker contains the image on what the user have picked on the camera roll. So each button has a specific value sent to my iCarouselView using NSUserDefaults. carousel1 for First slot and carousel2 for Second slot.
Here is what I wanna do: I want to forcefully make it stop to the index the user picks. (Which Im doing in my carouselDidEndScrollingAnimtaion)
In my carouselDidEndScrollingAnimation method i tested all of my condition(individually) it works perfectly in terms of comparing.
Then when I combine the conditions, the first Two comparison or STOP is RIGHT, but the next two are always wrong. Or sometimes Got mixed up.
I need to scroll the two specific indexes/integer which was User Picked( I already done that) was able to scroll 2 pairs of them but then the next two were always wrong because I think there indexes were adjusting.
PICTURES:
Image Below is my PhotoViewController which contained the Comparing Stage SETTING of my game.UIImageVIew with UIButton.Image that will be put in the number according to it will be Forcefully and should be forcefully shown.
When my iCarousel start then it stops for example in the image below(Which is not the same as the above):
Will be forcefully scroll to the inputted image in the PhotoViewController
Into:
Summary:
Its like this. I have a settingsView from there, I will import my images(Multiple) for Slot1 & Slot2.
Then in another View the PhotoViewController that is where the image above is shown. THe first column corresponds to 1st slot followed by the 2nd slot. if a view is pressed (for example No. 1 of Slot 1 it will load a thumbnail of images loading the images picked from Picker for the Slot 1.
You will have to do it 4 times(pair) ----> The displayed here I get their indexes via NSUserDefaults via button.tag then send to iCarouselView.
Then when you are done (pressed Done button) it will go to iCarouselView then, as shown above thats the view of it.
When pressed it will spin for couple of seconds, then when finished but not stop at the user picked in the PhotoView it will forcefully scroll to that index.
QUESTION:
Is there a way to make my array or my iCarousel.view not adjust their indexes when Im deleting. To still retain my indexes the right way. Or are there other solution like adjusting my array, the same as adjusting my PhotoViewController picked indexes too. Because I think that when my array retain their indexes even deleting I would be able to solve this problem. But still can't.
Hope you understand my question.
Is there a way to make my array or my iCarousel.view not adjust their indexes when Im deleting. To still retain my indexes the right way. Or are there other solution like adjusting my array, the same as adjusting my PhotoViewController picked indexes too. Because I think that when my array retain their indexes even deleting I would be able to solve this problem. But still can't.
The only way you have to modify the way iCarousel manages its indexes is by modifying the code. Indeed, if you look at the removeViewAtIndex method in iCarousel.m, you will see that indexes are managed through an NSDictionary, and at the moment of deleting, the dictionary is rearranged (items are reordered). You could take that method:
- (void)removeViewAtIndex:(NSInteger)index
{
NSMutableDictionary *newItemViews = [NSMutableDictionary dictionaryWithCapacity:[itemViews count] - 1];
for (NSNumber *number in [self indexesForVisibleItems])
{
NSInteger i = [number integerValue];
if (i < index)
{
[newItemViews setObject:[itemViews objectForKey:number] forKey:number];
}
else if (i > index)
{
[newItemViews setObject:[itemViews objectForKey:number] forKey:[NSNumber numberWithInteger:i - 1]];
}
}
self.itemViews = newItemViews;
}
You could apply the same logic to your array, so that the carousel and your array keep in sync. Of course, if you store the indexes somewhere (slot1/slot2/slot2/slot4?), you should also update their values after removing an element.
On the other hand, I think that what you are asking here is how to do something that you believe would solve the problem you have, but you are not really explaining what the problem is. Indeed, if I understand you correctly, what you do is:
spinning the carousel;
when the carousel stops, if it is not by chance on the desired item, you "force" it to scroll to that item.
There is no reason why this should not work after deleting some elements (unless iCarousel has some bugs, then the solution would be catching the bug). The only part is knowing which index is the one you would like to move to.
As a suggestion, I would start off by simplifying your delegate carouselDidEndScrollingAnimation method. Indeed, your carouselDidEndScrollingAnimation has a parameter called carousel, well, I think this is the only carousel you should ever be referring to in that method. If you don't see it, this is the reasoning: each of your carousel will stop scrolling and the carouselDidEndScrollingAnimation will be called; so that method will be called twice. Each time that method is executed you will modify the state of both carousel1 and carousel2 (by calling scrollToItemAtIndex); therefore, on each carousel you will call scrollToItemAtIndex twice.
This does no sound very correct to me. So you should find a way to scroll only carousel1 when carouselDidEndScrollingAnimation is called for carousel1 and to scroll only carousel2 when carouselDidEndScrollingAnimation is called for carousel2.
More generally, another point I would like to raise is that the idea of:
letting a carousel stop;
scrolling it again so that it reaches the desired position;
does not seem the best implementation possible since the user would see the carousel stopping and then starting over again.
The way I would approach this is by modifying directly iCarousel implementation so that it supports this specific behavior you need.
Concretely, give a look at the step method in iCarousel.m. This is called at each frame to produce the carousel animation. Now, in this method there is decelerating branch:
else if (decelerating)
{
CGFloat time = fminf(scrollDuration, currentTime - startTime);
CGFloat acceleration = -startVelocity/scrollDuration;
CGFloat distance = startVelocity * time + 0.5f * acceleration * powf(time, 2.0f);
scrollOffset = startOffset + distance;
[self didScroll];
if (time == (CGFloat)scrollDuration)
{
decelerating = NO;
if ([delegate respondsToSelector:#selector(carouselDidEndDecelerating:)])
{
[delegate carouselDidEndDecelerating:self];
}
if (scrollToItemBoundary || (scrollOffset - [self clampedOffset:scrollOffset]) != 0.0f)
{
if (fabsf(scrollOffset/itemWidth - self.currentItemIndex) < 0.01f)
{
//call scroll to trigger events for legacy support reasons
//even though technically we don't need to scroll at all
[self scrollToItemAtIndex:self.currentItemIndex duration:0.01];
}
else
{
[self scrollToItemAtIndex:self.currentItemIndex animated:YES];
}
}
else
{
CGFloat difference = (CGFloat)self.currentItemIndex - scrollOffset/itemWidth;
if (difference > 0.5)
{
difference = difference - 1.0f;
}
else if (difference < -0.5)
{
difference = 1.0 + difference;
}
toggleTime = currentTime - MAX_TOGGLE_DURATION * fabsf(difference);
toggle = fmaxf(-1.0f, fminf(1.0f, -difference));
}
}
}
and you see that when the carousel stops decelerating, it is scrolled again. This is exactly the same as you are doing, so you might find a way to modify this code and have the carousel scrolls exactly to the index you need. In this way you would get a far smoother spinning of the carousel.
Hope this helps and apologies for the lengthy reply.
Its a little difficult to know what the issue is here. Are you using a single NSMutableArray for the images and using the NSUserDefaults value to get the object at the index in the array?
Im not 100% sure on what is happening. What does the user do(and in what view) and what is triggered after that(which view is presented).
Are you trying to stop the "spinning" images on the image that is the same as the one picked from the previous view?
According to your images above, the images are off by a single index. Is this the case every time? Maybe there is an issue with your fetching from the array.
If you give me some more info I can help.
I looked through the code you pasted again and I think this might be your issue
if (twoSlot1 > [(UIImageView*)[self.carousel2 currentItemView] tag]){
[self.carousel1 scrollToItemAtIndex:(-twoSlot1)-2 duration: 3.5f];
} else {
[self.carousel1 scrollToItemAtIndex:-twoSlot1 duration: 3.5f];
}
On all other code blocks like that you have this where you call each carousel. In the above code you call carousel 1 twice.
if (slot2 > [(UIImageView*)[self.carousel1 currentItemView] tag]){
[self.carousel1 scrollToItemAtIndex:(-slot2)-2 duration: 3.0f];
} else {
[self.carousel1 scrollToItemAtIndex:-slot2 duration: 3.0f];
}
if (twoSlot2 > [(UIImageView*)[self.carousel2 currentItemView] tag]){
[self.carousel2 scrollToItemAtIndex:(-twoSlot2)-2 duration: 3.5f];
} else {
[self.carousel2 scrollToItemAtIndex:-twoSlot2 duration: 3.5f];
}
You call self.carousel1 when you should be calling number 2.
Is this correct?
Referring to your question. You want an array that does not change its members' indexes when a member is deleted from the array.
I guess you could use an NSMutableDictionary. It is an associative array so to say, where the indexes are of your choice and they remain unchanged when you delete a member from in between.
You may still use 0..n as your Index. You can still use some methods that you are familiar with from NSArray, such as count. You can use an enumerator to go through all members of the dictionary. On the other hand you can still use your for-loops as you are used to use them with arrays. Just be prepared that a) objectForKey:i may return nil if the key/index does not exist (e.g. was deleted) and that count retuns the number of the objects but not the highest index+1 as it does with arrays.
Not sure if I understand completely, but when one of the elements in your mutable array is deleted, rather than just deleting it, maybe insert it with another "dummy" place holder object? That way your indexes won't change at all when a delete occurs
I'm having a hard time understanding your overall problem, but from what I can gather the crux of your question is this:
Is there a way to make my array or my iCarousel.view not adjust their indexes when Im deleting.
I don't know whether it will solve your bigger issue, but using an NSMutableDictionary to simulate an array should allow you to do this. You can simply use the indices as the keys to the dictionary, and then when you remove the item associated with an index, no other indices will be adjusted as a result. For example:
NSMutableDictionary *arrayDict = [[NSMutableDictionary alloc] init];
[arrayDict setValue:foo forKey:[NSNumber numberWithInt:[arrayDict count]]];
[arrayDict setValue:bar forKey:[NSNumber numberWithInt:[arrayDict count]]];
[arrayDict setValue:fooBar forKey:[NSNumber numberWithInt:[arrayDict count]]];
And then you can access the object an at index with [arrayDict objectForKey:[NSNumber numberWithInt:index]].
Note that using an NSNumber for the key parameter of setValue:forKey: will generate a warning, but you can safely ignore this (or use the string representation if it bothers you).

When are a methods GUI operations actually carried out?

I am working on a web-services data processing app and I am trying to make the app run as quickly as possible. When a certain 3 finger pan gesture is performed, I call a method that sends updated information off to the server to get a new batch of images to update the existing ones with.
So lets say there are 15 images in an array, I filter through them with a 2 finger gesture, and then if I want to change something about them, I can do the 3 finger gesture, and I get that same set back, just tweaked a bit (contrast/brightness, etc.).
Is what I want though is to be able to update the imageView that is displaying the images after the first image has been retrieved, so as to give the user a feel for what the rest in the series are going to look like. But no matter what I try, and no matter how many different threads I try and implement, I can't get the imageView to update before the entire download is complete. Once the batch download is done (which is handled on a separate thread) the imageView updates with the new images and everything is great.
The first step in the process is this:
if(UIGestureRecognizerStateEnded == [recognize state]){
[self preDownload:windowCounter Level:levelCounter ForPane:tagNumber];// Where this method is what gets the first image, and tries to set it to the imageView
[self downloadAllImagesWithWL:windowCounter Level:levelCounter ForPane:tagNumber]; //And this method goes and gets all the rest of the images
}
This is my preDownload method:
-(void)preDownload:(int)window Level:(int)level ForPane:(int) pane{
int guidIndex = [[globalGuids objectAtIndex:pane] intValue];
UIImage *img = [DATA_CONNECTION getImageWithSeriesGUID:[guids objectAtIndex:guidIndex] ImageID:counter Window:window Level:level];
if(pane==0){
NSLog(#"0");
[imageView3 setImage:img];
}else if(pane==1){
NSLog(#"1");
[imageView31 setImage:img];
}else if(pane==2){
NSLog(#"2");
[imageView32 setImage:img];
}else if(pane==3){
NSLog(#"3");
[imageView33 setImage:img];
}
}
So by separating this out into two different methods (there are no threads being implemented at this point, these methods are being called before all that) I was thinking that after the preDownload method completed, that the imageView would update, and then control would continue on down into the downloadAllImagesWithWL method, but that doesn't appear to be the case.
Am I missing something simple here? What can I do to update my GUI elements before that second method is through running?
You are right. However the viewn won't refresh until your code reaches runloop. You can do 2 things:
Make your downloadAllImagesWithWL method async, so it will return after you called it, your main thread reaches runloop, gui updates, and the download method will tell your logic through a callback when its done.
OR
A simplier hackier (and bad) solution would be to run runloop for some time before you call your download method. Something like this: [[NSRunloop currentRunLoop] runUnitlDate: [Date dateWithTimeIntervalSinceNow: 0.1]]; It will run runloop for 0.1 second.
When the image is set, the image view will mark itself as needing display. The actual display won't occur until the beginning of the next run loop. In OS X, you can use -display to draw the view immediately, but I don't think Apple created a public method to do this on iOS. However, if the next method simply creates the background thread, then it will return quickly and the display update will probably occur before the thread finishes.

IPhone: different system timers?

I have been using mach_absolute_time() for all my timing functions so far. calculating how long between frames etc.
I now want to get the exact time touch input events happen using event.timestamp in the touch callbacks.
the problem is these two seem to use completely different timers. sure, you can get them both in seconds, but their origins are different and seemingly random...
is there any way to sync the two different timers?
or is there anyway to get access to the same timer that the touch input uses to generate that timestamp property? otherwise its next to useless.
Had some trouble with this myself. There isn't a lot of good documentation, so I went with experimentation. Here's what I was able to determine:
mach_absolute_time depends on the processor of the device. It returns ticks since the device was last rebooted (otherwise known as uptime). In order to get it in a human readable form, you have to modify it by the result from mach_timebase_info (a ratio), which will return billionth of seconds (or nanoseconds). To make this more usable I use a function like the one below:
#include <mach/mach_time.h>
int getUptimeInMilliseconds()
{
static const int64_t kOneMillion = 1000 * 1000;
static mach_timebase_info_data_t s_timebase_info;
if (s_timebase_info.denom == 0) {
(void) mach_timebase_info(&s_timebase_info);
}
// mach_absolute_time() returns billionth of seconds,
// so divide by one million to get milliseconds
return (int)((mach_absolute_time() * s_timebase_info.numer) / (kOneMillion * s_timebase_info.denom));
}
Get the initial difference between two i.e
what is returned by mach_absolute_time() initally when your application starts and also get the event.timestamp initially at the same time...
store the difference... it would remain same through out the time your application runs.. so you can use this time difference to convert one to another...
How about CFAbsoluteTimeGetCurrent?