IPhone App Build Successful But nothing shows - iphone

Very new to Iphone development here, I have a project which is successfully building (which is a first for me :) It loads the simulator but it just closes as soon as it loads, how can I debug this? It appears the Interface Builder xib files are not loading, I've added a xib thats from a hello world project, (they have different project names) Is this an issue?
Any advice would help,
Thanks!

You probably have an error in the Debugger Console. If it has to do with the XIB, it could be that you simply got the name wrong.
Another simple mistake is trying to use Outlets before viewDidLoad is called (for instance, in init).
In either case -- the message in the console will help.

Related

XPC connection interrupted in Xcode 7 for iOS 9

I recently updated to Xcode 7 and upgraded my iPhone to iOS 9. I have developed and released an iOS app that had worked perfectly fine on the latest version of iOS 8 and Xcode 6.
Upon trying to go through the process of updated the app for iOS 9 support, I am getting the most ridiculously strange error that has left me baffled.
I have done all the syntax corrections automatically through Xcode, and now my app builds properly. It even runs fine at first.
I have a button that segues to a view controller with a WebView. This view controller loads a link that will display either an image, website, or video from youtube. The content is loaded perfectly fine as always. However, the program will crash and reboot the simulator (and my iPhone) and send me to the lock screen when I click the Back button (I am on a navigation stack).
In Xcode, I get the following messages:
XPC Connection Interrupted.
Terminating since there is no system app.
I have Flurry analytics integrated in my app by the way, not sure if thats an issue.
How can I fix this issue? My searches for XPC connections do not seem to return problems similar to mine. I do not even have a clue what an XPC connection is, so why is this in my app anyway?
EDIT: I have found a workaround for the issue. I cannot really say it is a fix.
The crashing was occurring during the use of the method self.navigationController?.popViewControllerAnimated, when set to true. I happened to set this to false, and the crashing stops (now the transition looks awful).
I do not know why this works, and just adds to my confusion.
The problem lied in the storyboard for me as well. I created a new project and laid out the views and everything seemed to be working fine. I found these couple lines in the storyboard source (right click on storyboard and select view as -> source code) which weren't common between the working version and the broken version:
<keyCommands>
<keyCommand/>
</keyCommands>
I have no idea what those lines are supposed to do, or how they crept into my storyboard file, but they were what was crashing the app so hard that the phone had to restart. I removed those lines from my main project and everything worked again.
This error can be caused by executing a loop repeatedly. In my case it was a 'for' loop in which I reset the counting variable. As soon as I added an NSLog in the loop it was obvious.
I just faced the same problem. I don't know if that will help you, but I also think it's coming from the Storyboard:
In my case, the problem is coming from a UITextView. Whenever I try to change the default text inside it, I have this error. If I let the default text or leave it empty, the app works fine. Making an IBOutlet and changing the text programmatically works as well.
I tried with other UI elements, but only the UITextView seems to have this issue.
I have struggled with exact same error. Through a process of elimination I established that it had nothing to do with the any class but had to do with the storyboard. Luckily I keep regular backup copies and I tried to compare storyboards to establish what I had done - but could find nothing obvious.
The backup copy worked fine and I was able to copy my controller classes (from the faulty copy with the changes) into the backup copy and they worked fine.
I think there is a bug possibly in storyboards.
I have same error message when I place a subview in -layoutSubviews method:
-(void)layoutSubviews
{
[super layoutSubviews];
[self populateByImageViews];
}
It causes infinite cycle of layout process and crashes app. Don't place subviews in this place!
Deleting UITextView from the one of the view in Storybord removes the error in my case.
In valueChanged: method of a UIControl, I had the same problem
so I made the code inside valueChanged: to run in main thread and it solved the problem.
#IBAction func valueChanged(sender: AnyObject) {
dispatch_async(dispatch_get_main_queue(), {
//code
}
}
For me was some missing constraints with a UISearchBar, but the error was only in the simulator.
I only add some constraints and works better
For me it was xcode live issues caused by IB_DESIGNABLE
If you have any IB_DESIGNABLE in source files, the system's live tracker will check for issues in StoryBoard too. It may leads to unnecessary building.
To disable it-
Open Storyboard file. Editor -> Automatically Refresh Views (Uncheck)
If you needs to Disable Live issue tracking
XCode -> Preferences -> General -> Issues -> Uncheck Live Issues
Reference
My issue probably originated with some storyboard issue, but I cleaned the project, restarted Xcode AND restarted the simulator app and that fixed it.
When using QLPreviewController, I am confronted with this problem. Error messages as follows,
XPC connection interrupted
_BSMachError: (os/kern) invalid capability (20)
_BSMachError: (os/kern) invalid name (15)
Since XPC means OS X interprocess communication, so I think this can solve the problem, especial when updating the UI
dispatch_async(dispatch_get_main_queue(), ^{
// do what you want to do.
});
For Swift 4+, user
DispatchQueue.main.async {
//Your Code
}

Resetting iPhone Application

I have an application that is currently named "xxxx". The app runs and works perfectly without any problems. However, I have reached a stumbling point. When I try to load the application onto my iPhone, the pictures on my picker view seemed to have disappeared for some strange reason. I've done multiple hours of debugging and everything checks out normal. I then decided I wanted to change the product name from "xxxx" to "xxxx Redo". As soon as I did that, the application loaded perfectly normal (with the pictures in the Picker View as it should be).
In conclusion, it comes to find out that there is no actual bug in the programming aspect of it. However, my question comes up as to why does it not load the correct way with the original product name but then loads the right way when the product name is changed?
The second part of my question is if anyone knows of a way to fix the original application so that way it displays correctly again with the original name?
I have tried the following:
Cleaning the app
Trashing the .app file and rebuilding
Deleting the app on the iPhone and rebuilding.
These things sometimes just happen, you can try the following extra steps:
clean build folder in XCode (press alt while clicking Product menu)
reboot the phone (poweroff/poweron)
I have seen cases where it made a difference.

Xcode 4.2 is missing a .xib file?

So I'm pretty new to programming, so I downloaded Xcode 4.2 and got to work. I watched many online tutorials and the main problem I was having was that all the tutorials were for Xcode 4 and not 4.2, meaning when you chose empty application setting, it was missing the .xib file. So I found a tutorial on how to create a .xib file. I got through it all except for one step, and that was to drag the from the window outlet of the xAppdelegate to the window. I've tried this over and over, but it doesn't work.
Here is the tutorial if anyone needs to see it http://www.trappers.tk/site/2011/06/16/mainwindow-xib/
Please someone help me!
You need to hold Ctrl while dragging, else it will not work.
Guide.
As you Control-drag from an object to your source code, Interface Builder indicates where a new binding is valid. After you’ve made the connection, Xcode displays a dialog you use to configure the binding. You can use the dialog to configure all aspects of the binding.
Interface Builder uses the Xcode index to determine which key paths are valid, and can also discover what controller it should connect through—you can therefore connect from a user interface element such as a table column to a property in a model class header.
Check out the video here.
You should choose a SingleViewBased Application instead of Empty Application then study all files that how they connect with each other. You can choose Master Application also. They will help you.
see this Hello world Tutorial click me.
And Youtube is the best way to learning for beginners. Search tutorial video because action teach more than the text.

Deleted UILabel in Interface Builder still shows up

I am having a bug that has got me stumped. I created a label a short while ago that was just a placeholder to be replaced in the future. Finally, I get to replacing it with a button, so I delete the UILabel and put a UIButton in its place (keep in mind this is all in Interface Builder). When I run the program in the simulator, the new button isn't there and instead there is the old label which has been deleted. I have searched my whole program and I have no reference to this label, it is completely out of my program, yet it still appears in IB and my new button does not. I have tried Cleaning the program and quitting Xcode several times to no avail. If anybody knows of or has faced a similar problem I would love to hear your solution.
Thanks,
Kyle
It seems in your case NIBs are cached in Simulator, delete your app from inside Simulator and rebuild/reinstall then it shall be fine.
With xcode 3 I would have guessed that you did not save the xib file within Interface Buidler.
Still in xcode 4 I sometimes get the impression that not all changes come to effect for whatever reason. As if one or two source files do not get compiled at all.
Then I close xcode, save everything and start over again.

App crashes when trying to use UITableView

When launching my tab-based app, it crash when I'm trying to navigate to a tab with a UITableView in it, probably due to Interface Builder wrong connection I've made.
I have absolutely no idea why... I'm getting crazy over here!
I've simplified my code so now it contains 2 tabs; when trying to navigate to the non-active tab, the app crashes with no further explanation.
I've posted the simplified source here: source download.
Any help will b appreciated.
Load the name of the UIViewController in tab. VideosGalleryViewController was not mentioned in the class. Check the screen shot attached.