IOS notes (common knowledge points)

IOS notes (common knowledge points)

This is some notes I made when I was working on projects at the company .......

// 1. iphone development-change the color of the dot in UIPageControl

PageControl. currentPageIndicatorTintColor = [UIColor blackColor];

PageControl. pageIndicatorTintColor = [UIColor grayColor];

 

// 2. How does ios make the status bar white?

[[UIApplication sharedApplication] setStatusBarStyle: UIStatusBarStyleLightContent];

If not, add View controller-based status bar appearance NO in info. plist.

See http://beyondvincent.com/blog/2013/11/03/120-customize-navigation-status-bar-ios-7/

 

// 3. For example, modify the color and font of the default title "Yiyun miyin" in the navigation bar.

Self. title = @ "Yi Yun meiyin ";

Self. navigationController. navigationBar. titleTextAttributes =@{ UITextAttributeTextColor: [UIColor whiteColor], UITextAttributeFont: [UIFont boldSystemFontOfSize: 20]};

 

// 4. Set the rounded corner for the label

Label. layer. borderWidth = 1.0f;

Label. layer. cornerRadius = 5.0f;

 

// 5. The following method must be implemented to manually rotate the status bar

-(BOOL) shouldAutorotate

{

Return NO;

}

-(NSUInteger) supportedInterfaceOrientations

{

Return UIInterfaceOrientationMaskPortrait;

}

 

// 6. How to set the display to portrait only

Modify supportedInterfaceOrientations in info. plist to set item to portrait. This setting is global.

 

// 7. Use UIColor to display # convert the traditional color f6f6f6 to 240 in decimal format

UIColor * color = [UIColor colorWithRed: 240/255. 0 green: 240/255. 0 blue: 240/255. 0 alpha: 1];

 

// 8. Create a category, extension, protocol, and empty file

Cmd + n select the objective-c File-> File Type in ios Source (category, extension, protocol, empty File)

 

// 9. convert a view to an image

// Convert a view to an image

UIGraphicsBeginImageContext (oppositeImageView. bounds. size );

[OppositeImageView. layer renderInContext: UIGraphicsGetCurrentContext ()];

UIImage * oppositeImg = UIGraphicsGetImageFromCurrentImageContext ();

UIGraphicsEndImageContext ();

 

// 10. Achieve the drag effect of the Image view

-(Void) viewDidLoad {

[Super viewDidLoad];

// Create an image View

ImageView = [[UIImageView alloc] initWithFrame: CGRectMake (100,100,100,150)];

ImageView. userInteractionEnabled = YES;

ImageView. image = [UIImage imageNamed: @ "ad_1"];

 

// Translation gesture

UIPanGestureRecognizer * pan = [[UIPanGestureRecognizer alloc] initWithTarget: self action: @ selector (panAction :)];

[ImageView addGestureRecognizer: pan];

[Self. view addSubview: imageView];

}

// Drag event of the translation gesture

-(Void) panAction :( UIPanGestureRecognizer *) pan

{

CGPoint point = [pan translationInView: self. view];

Pan. view. center = CGPointMake (pan. view. center. x + point. x, pan. view. center. y + point. y );

[Pan setTranslation: CGPointZero inView: self. view];

}

// 11. Images can respond to events. For example, you can drag a UITextView to an image.

BackgrondImage. userInteractionEnabled = YES;