UIButton : How to create a UIButton Programmatically

Sample Code:

// Set a method for this

-(void) addButtonWithFrame :(CGRect ) btnFrame  andName: (NSString *) titleName

{

UIButton *addButton = [UIButton buttonWithType: UIButtonTypeCustom];

// (Value = 0) means NO Button Style.

/* iOS Library provide more Types of UIButton , like

1. UIButtonTypeRoundedRect (Value = 1), Means a Rounded-Rectangle Style
2. UIButtonTypeDetailDisclosure (Value = 2), Means a Details Disclosure Button
3. UIButtonTypeInfoLight (Value = 3), Means an Information button with light background
4. UIButtonTypeInfoDark (Value = 4), Means an Information Button with dark background
5. UIButtonTypeContactAdd (Value = 5), Means a contact add button.

You can choose any one of them. */

//Set Button Frame

addButton.frame = btnFrame;

//Set Tag

addButton.tag = cnt; //cnt = 0,1,2…..so on.

// Set Title

[addButton setTitle : titleName forState: UIControlSateNormal];

//If you want to user touch and title highlighted, changes the state like :

// [addButton setTitle : titleName forState: UIControlStateHighlighted];

//Set Title Color

[addButton setTitileColor: [UIColor darkGrayColor] forState: UIControlStateNormal];

//Set Font

addButton.titleLabel.font = [UIFont fontWithName: @ “FontName” size:14 ];

or

addButton.titleLabel.font = [UIFont systemFontOfSize:14];

//Set Image

[addButton setImage:[UIImage imageNamed:@ “ImageName_Normal”] forState: UIControlStateNormal];

[addButton setImage:[UIImage imageNamed:@ “ImageName_Highlighted”] forState: UIControlStateHighlighted];

// Set Background Image

[addButton setBackgroundImage:[UIImage imageNamed:@ “ImageNormal.png”] forState: UIControlStateNormal];// highlighted

[addButton setBackgroundImage:[UIImage imageNamed:@ “ImageHighlighted.png”] forState: UIControlStateHighlighted];

// Set your custom Image, means add a ImageView on Button

UIImageView *myImageView = [[UIImageView alloc] initWithFrame: CGRectMake( 0,0, btnFrame.frame.size.width, btnFrame.frame.size.height)];

myImageView.image = [UIImage imageNamed: @ “Image.png”];

[addButton addSubview: myImageView];

[myImageView release];

// Other way to set Image highlighted and normal with Strechable Image

UIImage *normalImage = [UIImage imageNamed:@ “normalImage.png”];

UIImage *strechableNormalImage = [normalImage stretchableImageWithLeftCapWidth: 14 topCapHeight: 0];

[addButton setBackgroundImage: strechableNormalImage forState: UIControlStateNormal];

UIImage *highlightedImage = [UIImage imageNamed:@ “highlightedImage.png”];

UIImage *strechableHighlightedImage = [highlightedImage  stretchableImageWithLeftCapWidth: 14 topCapHeight: 0];

[addButton setBackgroundImage: strechableHighlightedImage forState: UIControlStateHighlighted];

//Set Line Break Mode

addButton.titleLabel.lineBreakMode = UILineBreakModeTrailTruncation;

// Set Border Layer border Width and Color

// First you import and add QuartzCore Framework

addButton.layer.borderWidth = 2.0f;

addButton.layer.borderColor = [UIColor blackColor].cgcolor;

// setRadius Corner

addButton.layer.radiusCorner = 9.0f;

// Set Action on Button

[addButton addTarget: self  action:@selector(clickOnButtons:) forControlEvents: UIControlEventTouchUpInside];

// Add to SubView  

[self.view addSubview: addButton];

}

//Calling Method

[self addButtonWithFrame:CGRectMake(20,20,120,30) andName:@ “Close”];

Or

CGRect rect;

rect = CGRectMake (20,20,120,30);

NSString *btnName = @ “Close”;

[self addButtonWithFrame:rect andName:btnName];

UINavigationBar: How to customize Navigation Bar

By customization we can change look and feel of Navigation Bar. Below is sample code which demonstrates how to customize Navigation Bar.

We can achieve this by using Categories in Objective-C:
Code Sample:

/*********************************************************/

@interface UINavigationBar (CustomNavBarImage)

– (void) setNavBackgroundImage:(UIImage*)bgImage;

– (void) removeNavBackgroundImage ;

@end

/************************************************************/

//.m file (Implementaion file)

#import “UINavigationBar+CustomNavBarImage.h”

@implementation UINavigationBar (CustomNavBarImage)

– (void) setNavBackgroundImage:(UIImage*)bgImage

{

if (bgImage == NULL)

return;

UIImageView *myImageView= [[UIImageView alloc] initWithImage:bgImage];

myImageView.frame = CGRectMake(0,0,320,44);

[self addSubview:myImageView];

[myImageView release];

// If you want to add some buttons and title go through that

//[myImageView release];

UIButton *addButton = [UIButton buttonWithType: UIButtonTypeRoundedRect];//UIButtonTypeCustom

addButton .frame = CGRectMake(10, 0, 100, 44);

[addButton setTitle:@”Add” forState:UIControlStateNormal];

[addButton addTarget:self action:@selector(clickOnAddButton:) forControlEvents:UIControlEventTouchUpInside];

//Font size of title

addButton.titleLabel.font = [UIFont boldSystemFontOfSize:14];

[myImageView addSubview:addButton];

myImageView.userInteractionEnable = YES;

}

– (void) removeNavBackgroundImage

{

NSArray *subviewsArray = [self subviews];

for (int i=0; i<[subviewsArray count]; i++)

{

if ([[subviewsArray objectAtIndex:i]  isMemberOfClass:[UIImageView class]])

{

[[subviewsArray objectAtIndex:i] removeFromSuperview];

}

}

}

@end

// Calling

// Set Navigation Bar Image

[[self.navigationController navigationBar] performSelectorInBackground:@selector(setNavBackgroundImage:) withObject:bgImage];

// Remove Image

[[self.navigationController navigationBar] performSelector:@selector(removeNavBackgroundImage) withObject:nil];

// Second Simple Way : (Without Categories)

// Set  first this : self.NavigationController.navigationBarHidden = YES;

-(void) setCustomNavBar

{

UIImageView *myImage = [[UIImageView alloc] initWithFrame:CGRectMake (0,0,320,44)];

// set your background image name like NavBarImage.png

myImage.image = [UIImage imageNamed:@”yourBGImage”];

myImage.backgroundColor = [UIColor clearColor];

[self.view addSubview: myImage];

UIButton *addButton = [UIButton buttonWithType: UIButtonTypeRoundedRect];//UIButtonTypeCustom

addButton .frame = CGRectMake(10, 0, 100, 44);

[addButton setTitle:@”Add” forState:UIControlStateNormal];

[addButton addTarget:self action:@selector(clickOnAddButton:) forControlEvents:UIControlEventTouchUpInside];

//Font size of title

addButton.titleLabel.font = [UIFont boldSystemFontOfSize:14];

[myImage addSubview:addButton];

myImage.userInteractionEnable = YES;

}

//Called this function on viewdidload or loadView or viewWillAppear (according to your preference).

[self performSelector:@selector(setCustomNavBar)];

Other Methods are :

 

Until iOS 5 came out, we used drawRect override in AppDelegate to customize UINavigationBar.
Now iOS 5 give us some new method for styling (and old doesn’t work).
How to build app that will work on iOS 4 and iOS 5 with stylized UINavigationBar?
You must to do both!
In AppDelegate use this code:

@implementation UINavigationBar (UINavigationBarCategory)
– (void)drawRect:(CGRect)rect {
UIImage *img = [UIImage imageNamed:@”navbar.png”];
[img drawInRect:rect];
}
@end

and in

viewDidLoad method for iOS5 and above (in your view implementation):

if ([self.navigationController.navigationBar respondsToSelector:@selector( setBackgroundImage:forBarMetrics:)]){
[self.navigationController.navigationBar setBackgroundImage:[UIImage  imageNamed:@”navbar.png”] forBarMetrics:UIBarMetricsDefault];
}

If you see, here we are asking if navbar will respondToSelector to avoid crash on iOS4!
If you use this for iOS5:

if([[UINavigationBar appearance] respondsToSelector:@selector( setBackgroundImage:forBarMetrics:)]){
[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@”navbar_bg.png”] forBarMetrics:UIBarMetricsDefault];
}


Your app will not work on iOS4 because can’t found [UINavigationBar appearance].
But, if you want to target only iOS5 this snippet will work for whole app. You can put it just in didFinishLaunchingWithOptions method in AppDelegate:

[[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@”navbar_bg.png”] forBarMetrics:UIBarMetricsDefault];

Set the image using method setBackgroundImage:forBarMetrics. (ios 5 and above)

[[UINavigationBarappearance] setBackgroundImage: portrait

forBarMetrics:UIBarMetricsDefault];

[[UINavigationBarappearance] setBackgroundImage: landscape

forBarMetrics:UIBarMetricsLandscapePhone];

Create resizable images

UIImage *portrait = [[UIImageimageNamed:@”image1″]

resizableImageWithCapInsets:UIEdgeInsetsMake(0, 0, 0, 0)];

UIImage *landscape = [[UIImage imageNamed:@”image2″]

resizableImageWithCapInsets:UIEdgeInsetsMake(0, 0, 0,0)];

Set the attributes of Naviagtion Bar (to set the title font, color, shadow offset)

[[UINavigationBarappearance] setTitleTextAttributes:

[NSDictionarydictionaryWithObjectsAndKeys:

[UIColorcolorWithRed:255.0/255.0green:255.0/255.0blue:255.0/255.0alpha:1.0],

UITextAttributeTextColor,

[UIColorcolorWithRed:0.0green:0.0blue:0.0alpha:0.8],

UITextAttributeTextShadowColor,

[NSValuevalueWithUIOffset:UIOffsetMake(0, -1)],

UITextAttributeTextShadowOffset,

[UIFontfontWithName:@”Arial-Bold”size:0.0],

UITextAttributeFont,

nil]];

Similary, we can set the background image of UISegmentedControl and UITabBar, UIBarButtonItem etc.

UIImageView: Show Images from URL,Resources Folder, and Document Directory

Use the following functions to get Image from Web URL or Main Bundle (Resource Folder) or Document Directory

// From URL

-(UIImage *) getImageFromURL : (NSString *) urlString

{

NSURL *pathURL = [NSURL URLWithString: urlString];

NSData *imageData = [NSData dataWithContentOfURL:pathURL];

UIImage *getImage = [[UIImage alloc]initWithData:imageData];

return getImage;

}

// From Bundle

-(UIImage *) getImageFromResources_FileName: (NSString *)file_Name andFileType: (NSString *) file_Extension

{

NSString *filePath = [[NSBundle mainBundle] pathForResource : file_Name ofType: file_Extension];

UIImage *getImage = [UIImage imageWithContentsOfFile:filePath];

return getImage;

}

// From Document Directory (NSDocumentDirectory)

-(UIImage *) getImageFromDocumentDirectory_ImageName:(NSString *) imageName

{

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docDirectory = [paths objectAtIndex:0];
NSString *destPath = [docDirectory stringByAppendingPathComponent:imageName];//image.png
NSURL *url = [NSURL fileURLWithPath:destPath];
UIImage *getImage= [manager imageWithURL:url];

if (getImage)
{

UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:@”Image” message:@”Found” delegate:nil cancelButtonTitle:@”OK” otherButtonTitles:nil];
[alertView show];

}
else
{

getImage = [UIImage imageNamed:@”defaultImage.png”];
UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:@”Image” message:@”Not Found” delegate:nil
cancelButtonTitle:@”OK” otherButtonTitles:nil];
[alertView show];

}

return getImage;

}

Procedure:

#define FROM_RESOURCES 1

#define FROM_WEB_URL 2

#define FROM_DOC_DIR 3

/*******************************************Calling **************************************************/

UIImageView *showImage = [[UIImageView alloc] initWithFrame:CGRectMake(20,20,250,250)];

//Calling from Resources Folder

if(FROM_RESOURCES)

{

showImage.image = [self getImageFromResources_FileName:@”Niketan” andFileType:@”png/jpg”];

}

else if (FROM_WEB_URL)

//Calling from URL

{

showImage.image = [self getImageFromURL : @”your url”];

// @”http://www.yourweb.com/pictures/niketan.png&#8221;;

}

else

//Calling From Document Directory

{

showImage.image = [self getImageFromDocumentDirectory_ImageName: @”Vinay.png”];

}

[self.view addSubview: showImage];

Freshers Programming Question (Set – 1)

Hello Friends,

                     Here the some basic question lists in C and C++ programming language , which are most frequently asked questions in an freshers level / experienced interview in software companies in India.

1. Write a program to Swap two numbers :
   • using third variable
   • without third variable
   • using bit-wise operator 
2.  Write a program for 
   • Pass By Value
   • Pass By Reference
3. Recursion Program:
   1. Prime Number
   2. Factorial series
   3. Fibonacci Series
   4. Sum  of Series
   5. Palindrome
4. A partition of a positive integer n is a sequence of positive integers that sum to n. Write a program to print all non-increasing partitions of n.
   eg.   n=4
   4
   3 1
   2 2
   2 1 1
   1 1 1 1
5. Print this pattern:
   1
   2 3
   4 5 6 ,
   
   
   and         1
        2     2
     3    3    3.