A dSYM file is a &quot;debug symbols file&quot;. It is generated when the &quot;Strip Debug Symbols&quot; setting is enabled in the build settings of your project.

When this setting is enabled, symbol names of your objects are removed from the resulting compiled binary (one of the many countermeasures to try and prevent would be hackers/crackers from reverse engineering your code, amongst other optimisations for binary size, etc.).

dSYM files will likely change each time your app is compiled (probably every single time due to date stamping), and have nothing to do with the project settings.

They are useful for re-symbolicating your crash reports. With a stripped binary, you won&#39;t be able to read any crash reports without first re-symbolicating them. Without the dSYM the crash report will just show memory addresses of objects and methods. Xcode uses the dSYM to put the symbols back into the crash report and allow you to read it properly.

Ideally, your dSYM file shouldn&#39;t be tracked in your git repo. Like other binaries that change on building, it&#39;s not useful to keep them in source control. However, having that said, it is important that you keep the dSYM files for each distributed build (betas, press releases, app store distributions, etc.) somewhere safe so that you are able to symbolicate any crash reports you might get. Xcode does this automatically for you when you use the Archive option. The created archive contains your app and its dSYM and is stored within Xcode&#39;s derived data directory.

Say that I have a dataframe that looks like:

    Name Group_Id
    AAA  1
    ABC  1
    CCC  2
    XYZ  2
    DEF  3 
    YYH  3

How could I randomly select one (or more) row for each `Group_Id`? Say that I want one random draw per `Group_Id`, I would get:

    Name Group_Id
    AAA  1
    XYZ  2
    DEF  3
 

Python: Random selection per group

Java 8 introduces both [Lambda Expressions][1] and [Type Annotations][2].

With type annotations, it is possible to define Java annotations like the following:

    @Retention(RetentionPolicy.RUNTIME)
    @Target(ElementType.TYPE_USE)
    public @interface MyTypeAnnotation {
    	public String value();
    }

One can then use this annotation on any type reference like e.g.:

    Consumer&lt;String&gt; consumer = new @MyTypeAnnotation(&quot;Hello &quot;) Consumer&lt;String&gt;() {
    	@Override
    	public void accept(String str) {
    		System.out.println(str);
    	}
    };

Here is a complete example, that uses this annotation to print &quot;Hello World&quot;:

    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    import java.lang.reflect.AnnotatedType;
    import java.util.Arrays;
    import java.util.List;
    import java.util.function.Consumer;
    
    public class Java8Example {
    	@Retention(RetentionPolicy.RUNTIME)
    	@Target(ElementType.TYPE_USE)
    	public @interface MyTypeAnnotation {
    		public String value();
    	}
    	
    	public static void main(String[] args) {
    		List&lt;String&gt; list = Arrays.asList(&quot;World!&quot;, &quot;Type Annotations!&quot;);
    		testTypeAnnotation(list, new @MyTypeAnnotation(&quot;Hello &quot;) Consumer&lt;String&gt;() {
    			@Override
    			public void accept(String str) {
    				System.out.println(str);
    			}
    		});
    	}
    	
    	public static void testTypeAnnotation(List&lt;String&gt; list, Consumer&lt;String&gt; consumer){
    		MyTypeAnnotation annotation = null;
    		for (AnnotatedType t : consumer.getClass().getAnnotatedInterfaces()) {
    			annotation = t.getAnnotation(MyTypeAnnotation.class);
    			if (annotation != null) {
    				break;
    			}
    		}
    		for (String str : list) {
    			if (annotation != null) {
    				System.out.print(annotation.value());
    			}
    			consumer.accept(str);
    		}
    	}
    }

The output will be:

    Hello World! 
    Hello Type Annotations!

In Java 8 one can also replace the anonymous class in this example with a lambda expression:

    public static void main(String[] args) {
    	List&lt;String&gt; list = Arrays.asList(&quot;World!&quot;, &quot;Type Annotations!&quot;);
    	testTypeAnnotation(list, p -&gt; System.out.println(p));
    }

But since the compiler infers the Consumer type argument for the lambda expression, one is no longer able to annotate the created Consumer instance:

    testTypeAnnotation(list, @MyTypeAnnotation(&quot;Hello &quot;) (p -&gt; System.out.println(p))); // Illegal!

One could cast the lambda expression into a Consumer and then annotate the type reference of the cast expression:

    testTypeAnnotation(list,(@MyTypeAnnotation(&quot;Hello &quot;) Consumer&lt;String&gt;) (p -&gt; System.out.println(p))); // Legal!

But this will not produce the desired result, because the created Consumer class will not be annotated with the annotation of the cast expression. Output:

    World!
    Type Annotations!

Two questions:

 1. Is there any way to annotate a lambda expression similar to annotating a corresponding anonymous class, so one gets the expected &quot;Hello World&quot; output in the example above?

 2. In the example, where I did cast the lambda expression and annotated the casted type: Is there any way to receive this annotation instance at runtime, or is such an annotation always implicitly restricted to RetentionPolicy.SOURCE?

The examples have been tested with javac and the Eclipse compiler.

**Update**

I tried the suggestion from @assylias, to annotate the parameter instead, which produced an interesting result. Here is the updated test method:

    public static void testTypeAnnotation(List&lt;String&gt; list, Consumer&lt;String&gt; consumer){
    	MyTypeAnnotation annotation = null;
    	for (AnnotatedType t :  consumer.getClass().getAnnotatedInterfaces()) {
    		annotation = t.getAnnotation(MyTypeAnnotation.class);
    		if (annotation != null) {
    			break;
    		}
    	}
    	if (annotation == null) {
                // search for annotated parameter instead
    		loop: for (Method method : consumer.getClass().getMethods()) {
    			for (AnnotatedType t : method.getAnnotatedParameterTypes()) {
    				annotation = t.getAnnotation(MyTypeAnnotation.class);
    				if (annotation != null) {
    					break loop;
    				}
    			}
    		}
    	}
    	for (String str : list) {
    		if (annotation != null) {
    			System.out.print(annotation.value());
    		}
    		consumer.accept(str);
    	}
    }

Now, one can also produce the &quot;Hello World&quot; result, when annotating the parameter of an anonymous class:

    public static void main(String[] args) {
    	List&lt;String&gt; list = Arrays.asList(&quot;World!&quot;, &quot;Type Annotations!&quot;);
    	testTypeAnnotation(list, new Consumer&lt;String&gt;() {
            @Override
            public void accept(@MyTypeAnnotation(&quot;Hello &quot;) String str) {
                System.out.println(str);
            }
        });
    }

But annotating the parameter does *not* work for lambda expressions:

    public static void main(String[] args) {
    	List&lt;String&gt; list = Arrays.asList(&quot;World!&quot;, &quot;Type Annotations!&quot;);
    	testTypeAnnotation(list, (@MyTypeAnnotation(&quot;Hello &quot;) String str) -&gt;  System.out.println(str));
    }

Interestingly, it is also not possible to receive the name of the parameter (when compiling with javac -parameter), when using a lambda expression. I&#39;m not sure though, if this behavior is intended, if parameter annotations of lambdas have not yet been implemented, or if this should be considered a bug of the compiler.


  [1]: http://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html
  [2]: http://docs.oracle.com/javase/tutorial/java/annotations/type_annotations.html

Annotating the functional interface of a Lambda Expression

I&#39;m working on an app with another developer and they just submitted a release to the app store that was built on their computer. In order to make a build on my machine (that belongs to the same git commit), I have to alter the path to one of the libraries we use in my XCode project. Will any changes I make to the XCode project file change the dSYM? If I was able to make a build without modifying the XCode project file, would the dSYM file be the same?

How is a .dSYM file created?

<p>I'm working on an app with another developer and they just submitted a release to the app store that was built on their computer. In order to make a build on my machine (that belongs to the same git commit), I have to alter the path to one of the libraries we use in my XCode project. Will any changes I make to the XCode project file change the dSYM? If I was able to make a build without modifying the XCode project file, would the dSYM file be the same?</p>


XCode supports those 2 values for this Build Setting:

Build Settings &gt; Build Options &gt; Debug Information Format.

Could anybody explain the differences?


What&#39;s the difference between DWARF and DWARF with dSYM file?

I am using a UICollectionView in my project, where there are multiple cells of differing widths on a line. According to:
https://developer.apple.com/library/content/documentation/WindowsViews/Conceptual/CollectionViewPGforIOS/UsingtheFlowLayout/UsingtheFlowLayout.html

it spreads the cells out across the line with equal padding. This happens as expected, except I want to left justify them, and hard code a padding width.

I figure I need to subclass UICollectionViewFlowLayout, however after reading some of the tutorials etc online I just don&#39;t seem to get how this works.


Left Align Cells in UICollectionView

I can&#39;t seem to find anything on this.  Are there any Siri classes or API&#39;s in iOS7 that let you do text to speech?  All I am trying to do is something like the following:

    [siriInstance say:@&quot;This is a test&quot;];

And then have Siri say it from my app.

It seems we should be capable of doing this, no?  Seems like a trivial thing.



iOS Text To Speech Api

What is the content compression resistance and content hugging of a UIView? How do these relate to the intrinsic content size of a view?

What is the content compression resistance and content hugging of a UIView?

I want to customize my `NavigationBar` button and using my own images.

The question is what the size should be?

I found that the button size should be 40*40, so the image should be 80*80 for retina?



iOS navigation bar item image size

I have a list of effects in a table view. I have created a top right bar button which does a push segue to another view controller which helps create a new effect. Now I want to add push segues to the table view cells so that the effects values maybe loaded on the add effects view controller and I can save the edited values.

The question is can I create a push segue programmatically? If not can I pass the effect through a `prepareforsegue`? If I try to use a `prepareforsegue`, I run into a problem where control dragging from the `UITableView` does not let me create a push segue to the add effects view controller.

How to make a push segue when a UITableViewCell is selected

How can I change inactive icon/text color on iOS 7 tab bar? The one in gray color.

![enter image description here][1]


  [1]: http://i.stack.imgur.com/xbKKn.png

How to change inactive icon/text color on tab bar?

I&#39;m integrating **Google Analytics SDK 3.0** in my project. But I am getting **linker errors** when try to build my project.

As mentioned in the [documentation](https://developers.google.com/analytics/devguides/collection/ios/v3/#headers), I have linked following libraries in my project,

+ _libGoogleAnalyticsServices.a_
+ _AdSupport.framework_
+ _CoreData.framework_
+ _SystemConfiguration.framework_
+ _libz.dylib_

Even then, I get following errors on building the project,

    d: warning: directory not found for option &#39;-L&quot;/Users/....NameProject/Libraries/Google Analytics&quot;&#39;
    &quot;_sqlite3_bind_blob&quot;, referenced from:
      -[TAGDataLayerPersistentStoreImpl writeEntriesToDatabase:expireTime:] in libGoogleAnalyticsServices.a(TAGDataLayerPersistentStoreImpl.o)
    &quot;_sqlite3_bind_int&quot;, referenced from:
      -[TAGDataLayerPersistentStoreImpl deleteEntries:] in libGoogleAnalyticsServices.a(TAGDataLayerPersistentStoreImpl.o)
    &quot;_sqlite3_bind_int64&quot;, referenced from:
      -[TAGDataLayerPersistentStoreImpl writeEntriesToDatabase:expireTime:] in libGoogleAnalyticsServices.a(TAGDataLayerPersistentStoreImpl.o)
      -[TAGDataLayerPersistentStoreImpl peekEntryIds:] in libGoogleAnalyticsServices.a(TAGDataLayerPersistentStoreImpl.o)

    ....

What is causing these errors? Am I missing anything? 

Appreciate your help.

----------


**SOLUTION:**

I solved it by linking my project with `libsqlite3.0` library. The Google analytics documentation missed out mentioning to link this library. Hope this helps.



Google Analytics SDK 3.0 _sqlite3 linker errors in iOS

I have `UICollectionView` with horizontal scrolling and there are always 2 cells side-by-side per the entire screen. I need the scrolling to stop at the begining of a cell. With paging enabled, the collection view scrolls the whole page, which is 2 cells at once, and then it stops.

I need to enable scrolling by a single cell, or scrolling by multiple cells with stopping at the edge of the cell.

I tried to subclass `UICollectionViewFlowLayout` and to implement the method `targetContentOffsetForProposedContentOffset`, but so far I was only able to break my collection view and it stopped scrolling. Is there any easier way to achieve this and how, or do I really need to implement all methods of `UICollectionViewFlowLayout ` subclass? Thanks.

Paging UICollectionView by cells, not screen

The executable was signed with invalid entitlements.

**The entitlements specified in your application’s Code Signing Entitlements file do not match those specified in your provisioning profile.(0xE8008016).**

I am getting this error. please help me.

I have create the provisioning profile and change the bundle id. I have enable the keychain sharing from Target-&gt;Capabilities and generate the new .entitlement file. and i have also change the bundle id in that.

![enter image description here][1]

  [1]: http://i.stack.imgur.com/B9cVF.png

Entitlements file do not match those specified in your provisioning profile.(0xE8008016)

I am trying to launch my app on device. It is launching successfully on the simulator.

 - List item
 - I use 7.1 SDK
 - Xcode 5 
 - And the device is a 7.1 iPhone 4S


I have tried:

 - Clean
 - Clean Build Folder
 - Deleting app
 - Disconnecting/Reconnecting device
 - Booting device
 - restarting Xcode

What can I do to make it work?


Could it be something with Code Signing?


Currently i have it set to &#39;Dont Code Sign&#39;


Could not launch process launch failed: timed out waiting for app to launch

I am using the following codes to add two button to self.navigationItem.rightBarButtonItems, and I think in iOS7, the space between two buttons are too wide, is there a way to decrease the space between these two buttons?
    
    UIBarButtonItem *saveStyleButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@&quot;save.png&quot;] style:UIBarButtonItemStyleBordered target:self action:@selector(saveStyle)];
    
    UIBarButtonItem *shareStyleButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:@selector(shareStyle)];
    
    NSArray *arr= [[NSArray alloc] initWithObjects:shareStyleButton,saveStyleButton,nil];
    
    self.navigationItem.rightBarButtonItems=arr;

Appreciate any hint or idea. 

How to adjust space between two UIBarButtonItem in rightBarButtonItems

When an Xcode Service bot attempts to perform a build with `run unit tests` enabled, the build will always fail. When I look at the log file, the same error repeats many times:

    xcsbuildd[1966] &lt;Warning&gt;: [XCSBuildOperation.m:106 7368f310 +2126ms] Preflight connection to /var/XCSControl/com.apple.XCSTestUserPreflightService failed; retrying: No such file or directory

Followed by these error messages a few lines later:

    xcsbuildd[1966] &lt;Error&gt;: [XCSBuildOperation.m:102 7368f310 +2104ms] Timed out trying to connect to CG Session; giving up after 60 seconds
    xcsbuildd[1966] &lt;Error&gt;: [XCSOperation.m:33 7368f310 +0ms] Error Domain=XCSBuildServiceDomain Code=0 &quot;Cancelled integration because headless test environment is required but not available after 60s&quot; UserInfo=0x7fa952571bd0 {NSLocalizedDescription=Cancelled integration because headless test environment is required but not available after 60s}
    xcsbuildd[1966] &lt;Debug&gt;: [XCSOperation.m:28 7368f310 +0ms] Cancelling operation: XCSBuildOperation

I&#39;ve hit a brick wall with this, and can&#39;t find anything on it.

Has anyone had this problem and found a fix?

Xcode Service (Mavericks) errors when run unit tests is enabled

Crashlytics says &quot;We&#39;re missing a dSYM to process crashes&quot; and when I try to download dSYMs from Xcode (7.1), I get &quot;there are no dsyms available for download&quot;

Crashlytics: &quot;We&#39;re missing a dSYM to process crashes&quot;

I want to extract the dSYM file from but when I click on _&quot;Download dSYMs...&quot;_ in the _Organizer_ I get the follow message: &quot;There are no dSYMs available for download.&quot;. 

I&#39;m using Xcode 7.2 with a workspace generated by Cocoapods 0.39. 

How can I get them?

[![enter image description here][1]][1]


  [1]: http://i.stack.imgur.com/bSdOQ.png

Xcode - There are no dSYMs available for download

I need to download the dSYM file so, as I usually do, I went to iTunes connect -&gt; My app -&gt; Activity -&gt; All builds -&gt; latest version. 

&quot;Include symbols&quot; is Yes, but there is no link to download the dSYM file. 

The app was uploaded 3 weeks ago, so also it&#39;s not like it&#39;s processing. Am I missing something stupid? Any idea?

[![enter image description here][1]][1]


  [1]: http://i.stack.imgur.com/FPRf2.png

Content Type	Original Author	Original Content on Stackoverflow
Question	couchy	View Question on Stackoverflow
Solution 1 - Ios	Jasarien	View Answer on Stackoverflow

How is a .dSYM file created?

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Annotating the functional interface of a Lambda Expression

Python: Random selection per group

Attributions