Not updating UIView of subView? - ios

I have already posted " HERe" .
and Here actually What I need to Deserve
If I put this part of code [self loadLocationView] in UIButton and ViewDidLoad method , It works fine here.
but whenever I choose a location from TableVeiw and calling from a configureViewSlider method , It gets called to the method loadLocationView but Not updating UI.
Here I have tried so far.
-(void) configureViewSlider
{
if (_detailItem) {
Location=[_detailItem description];
//[self performSelectorOnMainThread:#selector(btnLocations:) withObject:nil waitUntilDone:false];
//[btnLocations sendActionsForControlEvents:UIControlEventTouchDown];
// [self loadLocationView];
[self performSelectorOnMainThread:#selector(loadLocationView) withObject:nil waitUntilDone:NO];
//[self loadView];
NSLog(#"Location %#", Location);
}
}
-(void) loadLocationView
{
_viewLocBangalore.frame= CGRectMake(10, 10, 303,255);
[self.view addSubview:_viewLocBangalore];
// [self.View bringSubviewToFront:_viewlocBangalore];
//[_viewLocBangalore setNeedsDisplay];
}
What else I have to do to achieve it . I have tried in all possible ways . but No use .
Please do some suggestion at least, I'm ready to approach for any way which is ready deserve my task (i..e.. I have added a UITableVieContrller which has locations , when user touches the Location , the UIView should update ).

Why u called configureViewSlider method then loadlocationview method directly location selection tableview method add this view:
_viewLocBangalore.frame= CGRectMake(10, 10, 303,255);
[self.view addSubview:_viewLocBangalore];

Related

setNeedsDisplay not working after adding subviews

I added about 500 views to my viewController.view.
This action took about 5 seconds on target.
Now I want the screen to refresh after each subview I'm adding, so the user will see them appears one by one on screen.
I tried this in my viewController:
-(void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
for(int i=0; i<500; i++)
{
//...Create aView
[self.view addsubview:aView];
[self.view setNeedsDisplay];
}
}
I run it and nothing happened for 5 seconds then all views appeared at once.
I made sure that [self.view setNeedsDisplay] called from the main thread context.
Any idea how to make those subviews appear one by one?
I found a simple solution. I added a new property to my viewController - 'subviewsCount' witch was initialised to 500. then called the following method from viewDidLoad:
-(void) addSubviewsToMotherView
{
self.subviewsCount -=1;
if (self.subviewsCount >= 0)
{
[UIView animateWithDuration:0.0
delay:0.0
options:UIViewAnimationOptionLayoutSubviews
animations:^{
[self methodToAddSubview];
}
completion:^(BOOL finished){
[self addSubviewsToMotherView];
}
];
}
}

UIAcitivity Indicator with UIAlertView

I am developing an app where the user will get to confirm some action via UIAlertView, if he confirms, I call a method that handles the operation, then I prepare to pop the view I am in to go back to another view after the method has been called.
I want to show UIActivityIndicatorView if the user presses confirm for as long as it takes to execute the method and go to that other view. I used startAnimating and stopAnimating in the proper location, but i never get to see the UI UIActivityIndicatorView shown, not for a sec.
I guess its related to some UI issues due to UIAlertView, not sure if I am correct though. I just need a clue on how to use UIActivityIndicatorView properly for a method execution time.
My code:
- (void)viewDidLoad
{
[super viewDidLoad];
self.activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
self.activityIndicator.alpha = 1.0;
self.activityIndicator.hidesWhenStopped = YES;
self.activityIndicator.center = self.view.center;
[self.view addSubview:self.activityIndicator];
}
-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if(buttonIndex == 1) {
[self.activityIndicator startAnimating];
ContactsTableViewController *contactTableView = [self getContactsTVC];
[contactTableView applyActionOnCells];
// doing some setup before poping off to the root view controller of my nav controller
[self.activityIndicator stopAnimating];
// then go to rootViewController
[self.navigationController popToRootViewControllerAnimated:YES];
}
}
I'm not 100% certain, but try to comment out the stopAnimating call and see if it shows up.
If that helps, applyActionOnCells probably blocks your main thread (where all UI stuff also happens) and the indicator never has a chance to show up before you hide it again.
In that case, try do the applyActionOnCells call in the background:
if(buttonIndex == 1) {
[self.activityIndicator startAnimating];
__block typeof(self) bself = self;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
ContactsTableViewController *contactTableView = [bself getContactsTVC];
[contactTableView applyActionOnCells];
dispatch_async(dispatch_get_main_queue(), ^{
[bself.activityIndicator stopAnimating];
// then go to rootViewController
[bself.navigationController popToRootViewControllerAnimated:YES];
});
});
}
Edit: see also an earlier question.

iOS GUI refresh

I am using setNeedsDisplay on my GUI, but there update is sometimes not done. I am using UIPageControllView, each page has UIScrollView with UIView inside.
I have the following pipeline:
1) application comes from background - called applicationWillEnterForeground
2) start data download from server
2.1) after data download is finished, trigger selector
3) use dispatch_async with dispatch_get_main_queue() to fill labels, images etc. with new data
3.1) call setNeedsDisplay on view (also tried on scroll view and page controller)
Problem is, that step 3.1 is called, but changes apper only from time to time. If I swap pages, the refresh is done and I can see new data (so download works correctly). But without manual page turn, there is no update.
Any help ?
Edit: code from step 3 and 3.1 (removed _needRefresh variables pointed in comments)
-(void)FillData {
dispatch_async(dispatch_get_main_queue(), ^{
NSString *stateID = [DataManager ConvertStateToStringFromID:_activeCity.actual_weather.state];
if ([_activeCity.actual_weather.is_night boolValue] == YES)
{
self.contentBgImage.image = [UIImage imageNamed:[NSString stringWithFormat:#"bg_%#_noc", [_bgs objectForKey:stateID]]];
if (_isNight == NO)
{
_bgTransparencyInited = NO;
}
_isNight = YES;
}
else
{
self.contentBgImage.image = [UIImage imageNamed:[NSString stringWithFormat:#"bg_%#", [_bgs objectForKey:stateID]]];
if (_isNight == YES)
{
_bgTransparencyInited = NO;
}
_isNight = NO;
}
[self.contentBgImage setNeedsDisplay]; //refresh background image
[self CreateBackgroundTransparency]; //create transparent background if colors changed - only from time to time
self.contentView.parentController = self;
[self.contentView FillData]; //Fill UIView with data - set labels texts to new ones
//_needRefresh is set to YES after application comes from background
[self.contentView setNeedsDisplay]; //This do nothing ?
[_grad display]; //refresh gradient
});
}
And here is selector called after data download (in MainViewController)
-(void)FinishDownload:(NSNotification *)notification
{
dispatch_async(dispatch_get_main_queue(), ^{
[_activeViewController FillData]; //call method shown before
//try call some more refresh - also useless
[self.pageControl setNeedsDisplay];
//[self reloadInputViews];
[self.view setNeedsDisplay];
});
}
In AppDelegate I have this for application comes from background:
-(void)applicationWillEnterForeground:(UIApplication *)application
{
MainViewController *main = (MainViewController *)[(SWRevealViewController *)self.window.rootViewController frontViewController];
[main UpdateData];
}
In MainViewController
-(void)UpdateData
{
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(FinishForecastDownload:) name:#"FinishDownload" object:nil]; //create selector
[[DataManager SharedManager] DownloadForecastDataWithAfterSelector:#"FinishDownload"]; //trigger download
}
try this:
[self.view performSelectorOnMainThread:#selector(setNeedsLayout) withObject:nil waitUntilDone:NO];
or check this link:
http://blackpixel.com/blog/2013/11/performselectoronmainthread-vs-dispatch-async.html
setNeedsDisplay triggers drawRect: and is used to "redraw the pixels" of the view , not to configure the view or its subviews.
You could override drawRect: and modify your labels, etc. there but that's not what it is made for and neither setNeedsLayout/layoutSubviews is.
You should create your own updateUI method where you use your fresh data to update the UI and not rely on specialized system calls meant for redrawing pixels (setNeedsDisplay) or adjusting subviews' frames (drawRect:).
You should set all your label.text's, imageView.image's, etc in the updateUI method. Also it is a good idea to try to only set those values through this method and not directly from any method.
None of proposed solutions worked. So at the end, I have simply remove currently showed screen from UIPageControllView and add this screen again. Something like changing the page there and back again programatically.
Its a bit slower, but works fine.

Method called only in viewDidApper but not in viewDidLoad, why?

I created a method that sets the title of a button based on a value.
This method needs to be called when opening the viewController and maybe refreshed when the controller appears again.
So i created the method and I called that method in viewDidLoad and viewDidApper but it seems to be called only when I change page and turn back to the view controller.
Why?
My code is
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
[self controlloRichieste];
......
}
-(void)viewDidAppear:(BOOL)animated{
[self controlloRichieste];
}
-(void)controlloRichieste{
//Numero richieste di contatto
NSString *numeroRichieste = #"1";
if([numeroRichieste isEqual:#"0"]){
[_labelRequestNumber setTitle:#"Nessuna" forState:UIControlStateNormal];
} else {
_labelRequestNumber.titleLabel.text = numeroRichieste;
_labelRequestNumber.tintColor = [UIColor redColor];
}
//Fine Numero richieste di contatto
}
You can also move that code to viewWillAppear so that it gets called each time it appears.
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[self controlloRichieste];
}
I see the problem now, try the other way around
-(void)controlloRichieste{
//Numero richieste di contatto
NSString *numeroRichieste = #"1";
if([numeroRichieste isEqual:#"0"]){
[_labelRequestNumber setTitle:#"Nessuna" forState:UIControlStateNormal];
} else {
_labelRequestNumber.tintColor = [UIColor redColor];
[[_labelRequestNumber titleLabel]setText:numeroRichieste];
}
//Fine Numero richieste di contatto
}
Change set the button color, before you change its titleLabel's text
I created a demo PROJECT for you, hope it's helpful!
When you open view first time the viewDidLoad is called and the viewDidAppeare.
The viewDidAppeare is called every time when the view is opened, when you push or present other view controller and go back to the maine one viewDidAppeare is called.
You should call:
[super viewDidAppear:animated];
The viewDidLoad is called just when the view is loaded and after that when it's deallocated and it needs to be allocated again. So mostly when you push or present other view controller and go back to the maine one viewDidLoad is not called.

self.view setNeedsDisplay and self.view setNeedsLayout are not working

I have a main view controller showing on the screen and a class (delegate) running in the background getting positions. When I get the result I call the delegate method in the view controller to update the label on the screen. I tried several ways but still no update to the screen.
Here is the method:
-(void) updateDisplay
{
NSLog(#"%#",myPosition.currentArea);
_area.text = [NSString stringWithFormat:#"area = %#",myPosition.currentShopArea];
//[self.view performSelectorOnMainThread:#selector(setNeedsDisplay) withObject:nil waitUntilDone:YES];
[self.view setNeedsDisplay];
//[self.view setNeedsLayout];
}
I check the console, it displays the correct area but on the screen still showing null. I tried all three ways (commented out above) but none of those update the screen.
You could try 2 things:
calling updateDisplay on the main thread:
[delegate performSelectorOnMainThread:#selector(updateDisplay) withObject:nil waitUntilDone:YES];
in the end, it is accessing UIKit, so better doing it right;
if that does not help, try with:
[_area setNeedsDisplay];
In this case also, if would be advisable to call the method on the main thread.

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