If you don&#39;t use Core Data, you could do:

    NSPredicate *predicateName = [NSPredicate predicateWithFormat:@&quot;name.length &gt; 0&quot;];

If the string is empty, this will fail (because `0 == 0`).  Similarly, if `name` is `nil`, it will also fail, because `[nil length] == 0`.

I think this should work:

    NSPredicate *predicateName = [NSPredicate predicateWithFormat:@&quot;name!=nil AND name!=&#39;&#39;&quot;]; 



    
     NSPredicate *predicateName = [NSPredicate predicateWithFormat:@&quot;name!=NULL&quot;];

This predicate worked for me:

    [NSPredicate predicateWithFormat:@&quot;(%K== nil) OR %K.length == 0&quot;, @&quot;imageUrl&quot;, @&quot;imageUrl&quot;]

I am using EF CF approach for a website with MySQL.
For some reason EF creates a column in my Post table called &quot;Discriminator&quot; and contains the VARCHAR &quot;Post&quot;.

Why is this column created? Can I do something to avoid it being created? Are there any advantages of having this column?

Entity framework code first creates &quot;discriminator&quot; column

I want to store an image(from url) into a sqlite database.

For that I use: 

    db = new DataBase(getApplicationContext());
    URL url = new URL(&quot;http://sree.cc/wp-content/uploads/schogini_team.png&quot;);
    URLConnection ucon = url.openConnection();
    InputStream is = ucon.getInputStream();
    BufferedInputStream bis = new BufferedInputStream(is,128);
    ByteArrayBuffer barb= new ByteArrayBuffer(128);
    
    int current = 0;
    while ((current = bis.read()) != -1) {
    	barb.append((byte) current);
    }
    
    ContentValues filedata= new ContentValues();
    
    filedata.put(DataBase.IMG_SRC,barb.toByteArray());
    
    db.insert(DataBase.Table_Img, null, filedata);

In the `Insert()`:

    public void insert(String tableImg, Object object,
    		ContentValues dataToInsert) {
    	// TODO Auto-generated method stub
    	String sql = &quot;INSERT INTO &quot;+tableImg+&quot; (&quot;+ID+&quot;,&quot;+IMG_SRC+&quot;) &quot; +
    			&quot;VALUES (&#39;&quot;+1+&quot;&#39;,&#39;&quot;+dataToInsert+&quot;&#39;)&quot;;
    	db.execSQL(sql);
    }


For the retrieval of image:

    Cursor cursor = db.selectDataToShow(DataBase.Table_Img, DataBase.IMG_SRC);
    
    byte[] imageByteArray=cursor.getBlob(cursor.getColumnIndex(DataBase.IMG_SRC));    	
    cursor.close();
    
    ByteArrayInputStream imageStream = new ByteArrayInputStream(imageByteArray);
    Bitmap theImage = BitmapFactory.decodeStream(imageStream);
    
    System.out.println(&quot;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt; &quot;+theImage);

So here I got `null`.

And in my database the value of image stored as: `Image=[B@43e5ac48]`

how to store Image as blob in Sqlite &amp; how to retrieve it?

I have an `NSArray` and need to filter out any strings that are null or rather, have &#39; &#39; (empty string). How do I do that? I have tried doing:

    NSPredicate *predicateName = [NSPredicate predicateWithFormat:@&quot;(name!=nil)&quot;]; 

but that doesn&#39;t seem to work. Or maybe it does but there are different kinds of null...

NSPredicate to test for NULL, and blank strings

I have an <code>NSArray</code> and need to filter out any strings that are null or rather, have ' ' (empty string). How do I do that? I have tried doing:
<pre><code class="hljs language-ini">NSPredicate *predicateName = [NSPredicate predicateWithFormat:@"(name!=nil)"]; 
</code></pre>
but that doesn't seem to work. Or maybe it does but there are different kinds of null...

Hi there I am trying to change the text that is showing in the delete button when a user swipes a uitableviewcell inside my tableview.

I have seen an example in another question thread that says to use this tableview delegate

    - (NSString *)tableView:(UITableView *)tableView titleForDeleteConfirmationButtonForRowAtIndexPath:(NSIndexPath *)indexPath

My question is, how do I use this method.. I am not sure how to use this.

How to change uitableview delete button text

i am trying to get index of an array through **indexOfObject** method as follows but when i try to log the value to test the index i get a garbage value.. for testing purposes i am having an array with values `{57,56,58..}` to get an index of lets say `56`,

    NSNumber *num = [NSNumber numberWithInteger:56];
    NSInteger Aindex = [myArray indexOfObject:num];
    NSLog(@&quot; %d&quot;,Aindex);

the value i get is something like `2323421`. what am i possibly doing wrong??

Getting Index of an Object from NSArray?

I am having problems testing my in-app purchases. I get back valid product identifiers, but upon purchase I receive the dreaded &quot;Cannot connect to iTunes Store&quot;. Interesting thing is that restore purchases seems to work - iTunes login pops up.

I have:
- Checked that my in-app purchases are cleared for sale
- Checked, rechecked my source code to be in sync with Apple&#39;s documentation
- Added appropiate test users
- app id does not contain wildcard
- in-app purchases are linked to the app (app itself is in developer rejected state, purchases are in ready to submit)
- waited
- reinstalled app, cleaned solution, all the voodoo stuff

&quot;Cannot connect to iTunes Store&quot; in-app purchases

I&#39;d like to check the contents of an XML file at a specific point of execution while debugging in Xcode. Is it possible to view the contents of the file, either through the Organizer (I&#39;m debugging using actual hardware devices, not the simulator), or by typing in some sort of command into the output/console?

I am using Xcode 4.

Is it possible to view the contents of files in the iOS Application sandbox while debugging?

I have a few (grouped style) tables in my iphone app (only on part of the screen and added with `Interface Builder` though, not subclassed from `UITableViewController`) that 80% of the time are small and will fit on the screen.  When the table fits on the screen, I&#39;d like to disable scrolling, to make it a bit cleaner.  But if the table goes off the screen (when rows are later added to it), I&#39;d like to enable scrolling again (because otherwise you can&#39;t see that content.)

Is there a way to do this?  I can&#39;t seem to figure it out.  I do know to do: 

    tableView.scrollEnabled = NO;

but I&#39;m not sure where, or if I have to calculate the table object size or something to get this to work. 

&lt;hr /&gt;
**Update**:
Here&#39;s the solution that finally worked for me:

    if (table.contentSize.height &lt; table.frame.size.height) {
	   table.scrollEnabled = NO;
	 }
    else {
	   table.scrollEnabled = YES;
	 }
I run this code after calling `reloadData` on the table, and it calculates the right sizes and appears to work.

`table.frame.size.height` is the actual size of the object (you can see this in `Interface Builder`) displayed on the screen, whereas `table.contentSize.height` is the heights of: the header, the footer, and the height of every cell added together.

How to disable scrolling in UITableView table when the content fits on the screen

In my singleton release method, I have it doing nothing:

    -(void) release {
      //A whole lot of nothing.
    }

But it produces this warning:


**Warning: Conflicting distributed object modifiers on return type in implementation of &#39;release&#39;**

I googled and saw others have the same error, but no explanation of the warning. Anyone know what the warning is about?



Singleton release method produces warning?

I just came across a crash showing a `NSInvalidArgumentException` with this message on an app which wasn&#39;t doing this before.

&gt; Application tried to present modally an active controller
&gt; UITabBarController: 0x83d7f00.

I have a `UITabBarController` which I create in the `AppDelegate` and give it the array of `UIViewControllers`.

One of them I want to present modally when tapped on it. I did that by implementing the delegate method

    - (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController

If that view controller is of the class of the one I want to present modally, I return NO and do

    [tabBarController presentModalViewController:viewController animated:YES];

And now I&#39;m getting that error, which seems to mean that you can&#39;t present modally a view controller that is active somewhere else (in the tabbar...)
I should say I&#39;m on XCode 4.2 Developer Preview 7, so this is iOS 5 (I know about the NDA, but I think I&#39;m not giving any forbidden details). I currently don&#39;t have an XCode installation to test if this crashes compiling against the iOS4 SDK, but I&#39;m almost entirely sure it doesn&#39;t.

I only wanted to ask if anyone has experienced this issue or has any suggestion

&quot;Application tried to present modally an active controller&quot;?

I have a tableview controller that displays a row of cells. Each cell has 3 buttons. I have numbered the tags for each cell to be 1,2,3. The problem is I don&#39;t know how to find on which cell a button is being pressed. I&#39;m currently only getting the sender&#39;s tag when one of the buttons has been pressed. Is there a way to get the cell row number as well when a button is pressed?

Getting row of UITableView cell on button press

I have an application with a view-based `NSTableView` in it.  Inside this table view, I have rows that have cells that have content consisting of a multi-row `NSTextField` with word-wrap enabled.  Depending on the textual content of the `NSTextField`, the size of the rows needed to display the cell will vary. 
 
I know that I can implement the `NSTableViewDelegate` method -`tableView:heightOfRow:` to return the height, but the height will be determined based on the word wrapping used on the `NSTextField`.  The word wrapping of the `NSTextField` is similarly based on how wide the `NSTextField` is… which is determined by the width of the `NSTableView`.

Soooo… I guess my question is… what is a good design pattern for this?  It seems like everything I try winds up being a convoluted mess. Since the TableView requires knowledge of the height of the cells to lay them out... and the `NSTextField` needs knowledge of it&#39;s layout to determine the word wrap… and the cell needs knowledge of the word wrap to determine it&#39;s height… it&#39;s a circular mess… and it&#39;s driving me *insane*.

Suggestions?

If it matters, the end result will also have editable `NSTextFields` that will resize to adjust to the text within them.  I already have this working on the view level, but the tableview does not yet adjust the heights of the cells.  I figure once I get the height issue worked out, I&#39;ll use the -`noteHeightOfRowsWithIndexesChanged` method to inform the table view the height changed… but it&#39;s still then going to ask the delegate for the height… hence, my quandry.

Thanks in advance!


View-based NSTableView with rows that have dynamic heights

I am new to iPhone development and `objective C`.
I have used `NSUserDefaults` to store some values in my app.
But I don&#39;t know that if there is any limit for storing values in `NSUserDefaults`.
Can anyone help me to know that.

Thanks in advance.

Is there any limit in storing values in NSUserDefaults?

Here is my current NSPredicate:

    NSPredicate *predicate = [NSPredicate predicateWithFormat:@&quot;UPC==%@ OR ItemID==%@&quot;, aUPCCode,aUPCCode];

How can I make this case insensitive?  

And I do not want to do any partial matching.  

Example if they enter 123 for aUPCCode I do not want to get 123, 123a, 123b, 123c, ect.  I would only want an exact match.

I thought about doing this but it seems a little ridiculous:

    NSPredicate *predicate = [NSPredicate predicateWithFormat:@&quot;UPC==%@ OR ItemID==%@ OR UPC==%@ OR ItemID==%@ OR UPC==%@ OR ItemID==%@&quot;, aUPCCode,aUPCCode,[ aUPCCode lowercaseString] ,[aUPCCode lowercaseString], [aUPCCode uppercaseString],[aUPCCode uppercaseString]];

case insensitive NSPredicate with single result in CoreData

I have an NSArray that I want to filter out certain objects using an NSPredicate, I was hoping I could use NOT IN since I saw that I can easily do an IN.

So I have my array:

    self.categoriesList

Then I get the values I want to remove:

    NSArray *parentIDs = [self.cateoriesList valueForKeyPath:@&quot;@distinctUnionOfObjects.ParentCategoryID&quot;];

This gives me a list of ParentCategoryID&#39;s for categories I DO NOT want to display, so I figure I can use an NSPredicate to remove them:

    self.cateoriesList = [self.cateoriesList filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@&quot;CategoryID NOT IN %@&quot;,parentIDs]];

This fails:

    reason: &#39;Unable to parse the format string &quot;CategoryID NOT IN %@&quot;&#39;

If I wanted to use just IN that works perfectly of course.
 

NSArray with NSPredicate using NOT IN

Most part of AddressBook framework is deprecated in iOS 9. In the new Contacts Framework [documentation][1] only shows how to fetch records matches a `NSPredicate`, but what if I want _all_ the record?


  [1]: https://developer.apple.com/library/prerelease/ios/documentation/Contacts/Reference/Contacts_Framework/index.html

Content Type	Original Author	Original Content on Stackoverflow
Question	Doz	View Question on Stackoverflow
Solution 1 - Ios	Dave DeLong	View Answer on Stackoverflow
Solution 2 - Ios	José Manuel Sánchez	View Answer on Stackoverflow
Solution 3 - Ios	chroww	View Answer on Stackoverflow
Solution 4 - Ios	Josip B.	View Answer on Stackoverflow

NSPredicate to test for NULL, and blank strings

Ios Problem Overview

Ios Solutions

Solution 1 - Ios

Solution 2 - Ios

Solution 3 - Ios

Solution 4 - Ios

how to store Image as blob in Sqlite & how to retrieve it?

Entity framework code first creates "discriminator" column

Attributions