[oc]- < getting started with UI> -- common controls - prompt dialog box and wait for the prompt (circle)

UIAlertController

 UIAlertController yes iOSUI Waiting prompt box control of the interface 

Be careful

• stay iOS 9.0 after The previous prompt dialog UIAlertView deprecated
  When we play UIAlertView When the object
  
• It also includes some video explanations Xcode The compilation environment of has become iOS 9 following
• stay iOS 9 after Xcode A new UIAlertController Object to create a dialog prompt box object

UIAlertController Usage of

• Create a warning prompt box object
• Develop a method of synthesizing access methods [email protected]

@interface ViewController : UIViewController<UIAlertViewDelegate> {
    
    //  Warning box view object 

    UIAlertController* _alertView ;
    //  Wait for the prompt object 
    // Display this control when downloading or loading large files , In the state of waiting for promotion 
}
@property(retain, nonatomic)   UIAlertController*  alertView;
@end

• Synchronize attributes and member variables

@implementation ViewController//  Implementation part 

@synthesize alertView = _alertView;
//  Wait for the prompt box   Not here 
@synthesize activityIndicator = _activityIndicator;

• Add one more button Use the same event function
  Circular creation It can be created separately
• The reason why the loop is created is that I put Prompt dialog And Wait for the prompt The two buttons together create
• Button to create another blog UIBUtton The creation of

UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        
        btn.frame = CGRectMake(100, 100 + 100 * i, 100, 40);
[btn setTitle:@" Warning dialog frame " forState:UIControlStateNormal];

//  Because I create loops   Set the sign   in order to button  Reference to the event 
 btn.tag = 100 + i

• add to button event function
• The reason for taking parameters is that we have more than one button

 [btn addTarget:self action:@selector(pressBtn :) 
 forControlEvents:UIControlEventTouchUpInside];

iOS9.0. above UIAlertController Create method

• 1） iOS 9 After that UIAlertController usage
  The topic and content of the prompt ：

 _alertView = [UIAlertController alertControllerWithTitle:@" Warning " 
 message:@" My mobile phone was invaded by me , About to shut down , Hit the money quickly " 
 preferredStyle:UIAlertControllerStyleAlert];

  Parameters 1: Warning    -- Is the title of our prompt box 
  Parameters 2： My mobile phone was invaded by me , About to shut down , Hit the money quickly " --- Prompt content 

• 2） Add options
  • Option one ：

  UIAlertAction* sure = [UIAlertAction actionWithTitle:@" determine " 
  style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action)
   {
    
            NSLog(@" determine ");
        }];

• Option 2 —cancle

UIAlertAction* cancel = [UIAlertAction actionWithTitle:@" Cancel " 
style:UIAlertActionStyleCancel handler:nil];

• 3） Add options to the view _alertView
  • _alertView Is the prompt box view we created

   [_alertView addAction:sure];
   [_alertView addAction:cancel];
        

• Show view

//  Show view 
        [self presentViewController:_alertView animated:YES 
        completion:nil];
        

effect

UIActivityIndicatorView

• Wait for the prompt object -- Display this control when downloading or loading large files , In the state of waiting for promotion

//  Wait for the prompt object 
    // Display this control when downloading or loading large files , In the state of waiting for promotion 
    UIActivityIndicatorView* _activityIndicator;

UIActivityIndicatorView The creation of

• Synthetic access methods

@property(retain, nonatomic)   UIActivityIndicatorView* activityIndicator;

• Synchronize attributes and member variables

@synthesize activityIndicator = _activityIndicator;

• establish button

UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        
 btn.frame = CGRectMake(100, 100 + 100 * i, 100, 40);

 [btn setTitle:@" Prompt dialog " forState:UIControlStateNormal];
   btn.tag = 100 + i;
        
        [btn addTarget:self action:@selector(pressBtn :) forControlEvents:UIControlEventTouchUpInside];
        
        [self.view addSubview:btn];

        

• add to button event
  • Wait for the indicator wide High is unchangeable

    _activityIndicator = [[UIActivityIndicatorView alloc]
     initWithFrame:CGRectMake(100, 300, 80, 80)] ;

• Wait for the indicator to turn into what color

self.view .backgroundColor = [UIColor whiteColor];

[self.view addSubview:_activityIndicator];
        
  // Start the animated screen display 
 [_activityIndicator startAnimating];

effect

• When we click the prompt dialog The circles in the figure will appear

Wait for the deactivation of the dialog box

When we don't need this effect , Enter this line of code to not display the animation

 // Stop waiting for dialog 
 [_activityIndicator stopAnimating];