App中不可能少了彈框，彈框是交互的必要形式，使用起來也非常簡單，不過最近需要自定義一個彈框，雖然iOS本身的彈框已經能滿足大部分的需求，但是不可避免還是需要做一些自定義的工作。iOS7之前是可以自定義AlterView的，就是繼承一下UIAlterView，然後初始化的時候通過addSubview添加自定義的View，但是iOS7之後這樣做就不行了，不過還好有開源項目可以解決這個問題。   iOS默認彈框   viewDidLoad中添加兩個按鈕，代碼如下:         UIButton  *orignalBtn=[[UIButton alloc]initWithFrame:CGRectMake(100, 40, 100, 50)]; [orignalBtn setBackgroundColor:[UIColor greenColor]]; [orignalBtn setTitle:@"iOS彈框" forState:UIControlStateNormal]; [orignalBtn addTarget:self action:@selector(orignalShow) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:orignalBtn];       UIButton  *customlBtn=[[UIButton alloc]initWithFrame:CGRectMake(100, 140, 100, 50)]; [customlBtn setBackgroundColor:[UIColor redColor]]; [customlBtn setTitle:@"自定義彈框" forState:UIControlStateNormal]; [customlBtn addTarget:self action:@selector(customShow) forControlEvents:UIControlEventTouchUpInside]; [self.view addSubview:customlBtn];     　響應默認彈框事件:     -(void)orignalShow{     UIAlertView *alterView=[[UIAlertView alloc]initWithTitle:@"提示" message:@"博客園-Fly_Elephant" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"確定", nil];     [alterView show]; } 　　效果如下:           自定義彈框   主要解決iOS7之後的系統無法自定義彈框的問題，使用開源項目，項目地址:https://github.com/wimagguc/ios-custom-alertview,其實就是自定義了一個類:   CustomIOSAlertView.h     #import <UIKit/UIKit.h>   @protocol CustomIOSAlertViewDelegate   - (void)customIOS7dialogButtonTouchUpInside:(id)alertView clickedButtonAtIndex:(NSInteger)buttonIndex;   @end   @interface CustomIOSAlertView : UIView<CustomIOSAlertViewDelegate>   @property (nonatomic, retain) UIView *parentView;    // The parent view this 'dialog' is attached to @property (nonatomic, retain) UIView *dialogView;    // Dialog's container view @property (nonatomic, retain) UIView *containerView; // Container within the dialog (place your ui elements here)   @property (nonatomic, assign) id<CustomIOSAlertViewDelegate> delegate; @property (nonatomic, retain) NSArray *buttonTitles; @property (nonatomic, assign) BOOL useMotionEffects;   @property (copy) void (^onButtonTouchUpInside)(CustomIOSAlertView *alertView, int buttonIndex) ;   - (id)init;   /*!  DEPRECATED: Use the [CustomIOSAlertView init] method without passing a parent view.  */ - (id)initWithParentView: (UIView *)_parentView __attribute__ ((deprecated));   - (void)show; - (void)close;   - (IBAction)customIOS7dialogButtonTouchUpInside:(id)sender; - (void)setOnButtonTouchUpInside:(void (^)(CustomIOSAlertView *alertView, int buttonIndex))onButtonTouchUpInside;   - (void)deviceOrientationDidChange: (NSNotification *)notification; - (void)dealloc;   @end CustomIOSAlertView.m#import "CustomIOSAlertView.h" #import <QuartzCore/QuartzCore.h>   const static CGFloat kCustomIOSAlertViewDefaultButtonHeight       = 50; const static CGFloat kCustomIOSAlertViewDefaultButtonSpacerHeight = 1; const static CGFloat kCustomIOSAlertViewCornerRadius              = 7; const static CGFloat kCustomIOS7MotionEffectExtent                = 10.0;   @implementation CustomIOSAlertView   CGFloat buttonHeight = 0; CGFloat buttonSpacerHeight = 0;   @synthesize parentView, containerView, dialogView, onButtonTouchUpInside; @synthesize delegate; @synthesize buttonTitles; @synthesize useMotionEffects;   - (id)initWithParentView: (UIView *)_parentView {     self = [self init];     if (_parentView) {         self.frame = _parentView.frame;         self.parentView = _parentView;     }     return self; }   - (id)init {     self = [super init];     if (self) {         self.frame = CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, [UIScreen mainScreen].bounds.size.height);           delegate = self;         useMotionEffects = false;         buttonTitles = @[@"Close"];                   [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];           [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(deviceOrientationDidChange:) name:UIDeviceOrientationDidChangeNotification object:nil];         [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];         [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];     }     return self; }   // Create the dialog view, and animate opening the dialog - (void)show {     dialogView = [self createContainerView];         dialogView.layer.shouldRasterize = YES;     dialogView.layer.rasterizationScale = [[UIScreen mainScreen] scale];         self.layer.shouldRasterize = YES;     self.layer.rasterizationScale = [[UIScreen mainScreen] scale];   #if (defined(__IPHONE_7_0))     if (useMotionEffects) {         [self applyMotionEffects];     } #endif       self.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0];       [self addSubview:dialogView];       // Can be attached to a view or to the top most window     // Attached to a view:     if (parentView != NULL) {         [parentView addSubview:self];       // Attached to the top most window     } else {           // On iOS7, calculate with orientation         if (floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_7_1) {                           UIInterfaceOrientation interfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation];             switch (interfaceOrientation) {                 case UIInterfaceOrientationLandscapeLeft:                     self.transform = CGAffineTransformMakeRotation(M_PI * 270.0 / 180.0);                     break;                                       case UIInterfaceOrientationLandscapeRight:                     self.transform = CGAffineTransformMakeRotation(M_PI * 90.0 / 180.0);                     break;                                       case UIInterfaceOrientationPortraitUpsideDown:                     self.transform = CGAffineTransformMakeRotation(M_PI * 180.0 / 180.0);                     break;                                       default:                     break;             }                           [self setFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];           // On iOS8, just place the dialog in the middle         } else {               CGSize screenSize = [self countScreenSize];             CGSize dialogSize = [self countDialogSize];             CGSize keyboardSize = CGSizeMake(0, 0);               dialogView.frame = CGRectMake((screenSize.width - dialogSize.width) / 2, (screenSize.height - keyboardSize.height - dialogSize.height) / 2, dialogSize.width, dialogSize.height);           }           [[[[UIApplication sharedApplication] windows] firstObject] addSubview:self];     }       dialogView.layer.opacity = 0.5f;     dialogView.layer.transform = CATransform3DMakeScale(1.3f, 1.3f, 1.0);       [UIView animateWithDuration:0.2f delay:0.0 options:UIViewAnimationOptionCurveEaseInOut                      animations:^{                          self.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.4f];                          dialogView.layer.opacity = 1.0f;                          dialogView.layer.transform = CATransform3DMakeScale(1, 1, 1);                      }                      completion:NULL      ];   }   // Button has been touched - (IBAction)customIOS7dialogButtonTouchUpInside:(id)sender {     if (delegate != NULL) {         [delegate customIOS7dialogButtonTouchUpInside:self clickedButtonAtIndex:[sender tag]];     }       if (onButtonTouchUpInside != NULL) {         onButtonTouchUpInside(self, (int)[sender tag]);     } }   // Default button behaviour - (void)customIOS7dialogButtonTouchUpInside: (CustomIOSAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {     NSLog(@"Button Clicked! %d, %d", (int)buttonIndex, (int)[alertView tag]);     [self close]; }   // Dialog close animation then cleaning and removing the view from the parent - (void)close {     CATransform3D currentTransform = dialogView.layer.transform;       if (floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_7_1) {         CGFloat startRotation = [[dialogView valueForKeyPath:@"layer.transform.rotation.z"] floatValue];         CATransform3D rotation = CATransform3DMakeRotation(-startRotation + M_PI * 270.0 / 180.0, 0.0f, 0.0f, 0.0f);           dialogView.layer.transform = CATransform3DConcat(rotation, CATransform3DMakeScale(1, 1, 1));     }       dialogView.layer.opacity = 1.0f;       [UIView animateWithDuration:0.2f delay:0.0 options:UIViewAnimationOptionTransitionNone                      animations:^{                          self.backgroundColor = [UIColor colorWithRed:0.0f green:0.0f blue:0.0f alpha:0.0f];                          dialogView.layer.transform = CATransform3DConcat(currentTransform, CATransform3DMakeScale(0.6f, 0.6f, 1.0));                          dialogView.layer.opacity = 0.0f;                      }                      completion:^(BOOL finished) {                          for (UIView *v in [self subviews]) {                              [v removeFromSuperview];                          }                          [self removeFromSuperview];                      }      ]; }   - (void)setSubView: (UIView *)subView {     containerView = subView; }   // Creates the container view here: create the dialog, then add the custom content and buttons - (UIView *)createContainerView {     if (containerView == NULL) {         containerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 300, 150)];     }       CGSize screenSize = [self countScreenSize];     CGSize dialogSize = [self countDialogSize];       // For the black background     [self setFrame:CGRectMake(0, 0, screenSize.width, screenSize.height)];       // This is the dialog's container; we attach the custom content and the buttons to this one     UIView *dialogContainer = [[UIView alloc] initWithFrame:CGRectMake((screenSize.width - dialogSize.width) / 2, (screenSize.height - dialogSize.height) / 2, dialogSize.width, dialogSize.height)];       // First, we style the dialog to match the iOS7 UIAlertView >>>     CAGradientLayer *gradient = [CAGradientLayer layer];     gradient.frame = dialogContainer.bounds;     gradient.colors = [NSArray arrayWithObjects:                        (id)[[UIColor colorWithRed:218.0/255.0 green:218.0/255.0 blue:218.0/255.0 alpha:1.0f] CGColor],                        (id)[[UIColor colorWithRed:233.0/255.0 green:233.0/255.0 blue:233.0/255.0 alpha:1.0f] CGColor],                        (id)[[UIColor colorWithRed:218.0/255.0 green:218.0/255.0 blue:218.0/255.0 alpha:1.0f] CGColor],                        nil];       CGFloat cornerRadius = kCustomIOSAlertViewCornerRadius;     gradient.cornerRadius = cornerRadius;     [dialogContainer.layer insertSublayer:gradient atIndex:0];       dialogContainer.layer.cornerRadius = cornerRadius;     dialogContainer.layer.borderColor = [[UIColor colorWithRed:198.0/255.0 green:198.0/255.0 blue:198.0/255.0 alpha:1.0f] CGColor];     dialogContainer.layer.borderWidth = 1;     dialogContainer.layer.shadowRadius = cornerRadius + 5;     dialogContainer.layer.shadowOpacity = 0.1f;     dialogContainer.layer.shadowOffset = CGSizeMake(0 - (cornerRadius+5)/2, 0 - (cornerRadius+5)/2);     dialogContainer.layer.shadowColor = [UIColor blackColor].CGColor;     dialogContainer.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:dialogContainer.bounds cornerRadius:dialogContainer.layer.cornerRadius].CGPath;       // There is a line above the button     UIView *lineView = [[UIView alloc] initWithFrame:CGRectMake(0, dialogContainer.bounds.size.height - buttonHeight - buttonSpacerHeight, dialogContainer.bounds.size.width, buttonSpacerHeight)];     lineView.backgroundColor = [UIColor colorWithRed:198.0/255.0 green:198.0/255.0 blue:198.0/255.0 alpha:1.0f];     [dialogContainer addSubview:lineView];     // ^^^       // Add the custom container if there is any     [dialogContainer addSubview:containerView];       // Add the buttons too     [self addButtonsToView:dialogContainer];       return dialogContainer; }   // Helper function: add buttons to container - (void)addButtonsToView: (UIView *)container {     if (buttonTitles==NULL) { return; }       CGFloat buttonWidth = container.bounds.size.width / [buttonTitles count];       for (int i=0; i<[buttonTitles count]; i++) {           UIButton *closeButton = [UIButton buttonWithType:UIButtonTypeCustom];           [closeButton setFrame:CGRectMake(i * buttonWidth, container.bounds.size.height - buttonHeight, buttonWidth, buttonHeight)];           [closeButton addTarget:self action:@selector(customIOS7dialogButtonTouchUpInside:) forControlEvents:UIControlEventTouchUpInside];         [closeButton setTag:i];           [closeButton setTitle:[buttonTitles objectAtIndex:i] forState:UIControlStateNormal];         [closeButton setTitleColor:[UIColor colorWithRed:0.0f green:0.5f blue:1.0f alpha:1.0f] forState:UIControlStateNormal];         [closeButton setTitleColor:[UIColor colorWithRed:0.2f green:0.2f blue:0.2f alpha:0.5f] forState:UIControlStateHighlighted];         [closeButton.titleLabel setFont:[UIFont boldSystemFontOfSize:14.0f]];         [closeButton.layer setCornerRadius:kCustomIOSAlertViewCornerRadius];           [container addSubview:closeButton];     } }   // Helper function: count and return the dialog's size - (CGSize)countDialogSize {     CGFloat dialogWidth = containerView.frame.size.width;     CGFloat dialogHeight = containerView.frame.size.height + buttonHeight + buttonSpacerHeight;       return CGSizeMake(dialogWidth, dialogHeight); }   // Helper function: count and return the screen's size - (CGSize)countScreenSize {     if (buttonTitles!=NULL && [buttonTitles count] > 0) {         buttonHeight       = kCustomIOSAlertViewDefaultButtonHeight;         buttonSpacerHeight = kCustomIOSAlertViewDefaultButtonSpacerHeight;     } else {         buttonHeight = 0;         buttonSpacerHeight = 0;     }       CGFloat screenWidth = [UIScreen mainScreen].bounds.size.width;     CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height;       // On iOS7, screen width and height doesn't automatically follow orientation     if (floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_7_1) {         UIInterfaceOrientation interfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation];         if (UIInterfaceOrientationIsLandscape(interfaceOrientation)) {             CGFloat tmp = screenWidth;             screenWidth = screenHeight;             screenHeight = tmp;         }     }           return CGSizeMake(screenWidth, screenHeight); }   #if (defined(__IPHONE_7_0)) // Add motion effects - (void)applyMotionEffects {       if (floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_6_1) {         return;     }       UIInterpolatingMotionEffect *horizontalEffect = [[UIInterpolatingMotionEffect alloc] initWithKeyPath:@"center.x"                                                                                                     type:UIInterpolatingMotionEffectTypeTiltAlongHorizontalAxis];     horizontalEffect.minimumRelativeValue = @(-kCustomIOS7MotionEffectExtent);     horizontalEffect.maximumRelativeValue = @( kCustomIOS7MotionEffectExtent);       UIInterpolatingMotionEffect *verticalEffect = [[UIInterpolatingMotionEffect alloc] initWithKeyPath:@"center.y"                                                                                                   type:UIInterpolatingMotionEffectTypeTiltAlongVerticalAxis];     verticalEffect.minimumRelativeValue = @(-kCustomIOS7MotionEffectExtent);     verticalEffect.maximumRelativeValue = @( kCustomIOS7MotionEffectExtent);       UIMotionEffectGroup *motionEffectGroup = [[UIMotionEffectGroup alloc] init];     motionEffectGroup.motionEffects = @[horizontalEffect, verticalEffect];       [dialogView addMotionEffect:motionEffectGroup]; } #endif   - (void)dealloc {     [[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];       [[NSNotificationCenter defaultCenter] removeObserver:self name:UIDeviceOrientationDidChangeNotification object:nil];     [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];     [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil]; }   // Rotation changed, on iOS7 - (void)changeOrientationForIOS7 {       UIInterfaceOrientation interfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation];           CGFloat startRotation = [[self valueForKeyPath:@"layer.transform.rotation.z"] floatValue];     CGAffineTransform rotation;           switch (interfaceOrientation) {         case UIInterfaceOrientationLandscapeLeft:             rotation = CGAffineTransformMakeRotation(-startRotation + M_PI * 270.0 / 180.0);             break;                       case UIInterfaceOrientationLandscapeRight:             rotation = CGAffineTransformMakeRotation(-startRotation + M_PI * 90.0 / 180.0);             break;                       case UIInterfaceOrientationPortraitUpsideDown:             rotation = CGAffineTransformMakeRotation(-startRotation + M_PI * 180.0 / 180.0);             break;                       default:             rotation = CGAffineTransformMakeRotation(-startRotation + 0.0);             break;     }       [UIView animateWithDuration:0.2f delay:0.0 options:UIViewAnimationOptionTransitionNone                      animations:^{                          dialogView.transform = rotation;                                                 }                      completion:nil      ];       }   // Rotation changed, on iOS8 - (void)changeOrientationForIOS8: (NSNotification *)notification {       CGFloat screenWidth = [UIScreen mainScreen].bounds.size.width;     CGFloat screenHeight = [UIScreen mainScreen].bounds.size.height;       [UIView animateWithDuration:0.2f delay:0.0 options:UIViewAnimationOptionTransitionNone                      animations:^{                          CGSize dialogSize = [self countDialogSize];                          CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;                          self.frame = CGRectMake(0, 0, screenWidth, screenHeight);                          dialogView.frame = CGRectMake((screenWidth - dialogSize.width) / 2, (screenHeight - keyboardSize.height - dialogSize.height) / 2, dialogSize.width, dialogSize.height);                      }                      completion:nil      ];         }   // Handle device orientation changes - (void)deviceOrientationDidChange: (NSNotification *)notification {     // If dialog is attached to the parent view, it probably wants to handle the orientation change itself     if (parentView != NULL) {         return;     }       if (floor(NSFoundationVersionNumber) <= NSFoundationVersionNumber_iOS_7_1) {         [self changeOrientationForIOS7];     } else {         [self changeOrientationForIOS8:notification];     } }   // Handle keyboard show/hide changes - (void)keyboardWillShow: (NSNotification *)notification {     CGSize screenSize = [self countScreenSize];     CGSize dialogSize = [self countDialogSize];     CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;       UIInterfaceOrientation interfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation];     if (UIInterfaceOrientationIsLandscape(interfaceOrientation)) {         CGFloat tmp = keyboardSize.height;         keyboardSize.height = keyboardSize.width;         keyboardSize.width = tmp;     }       [UIView animateWithDuration:0.2f delay:0.0 options:UIViewAnimationOptionTransitionNone                      animations:^{                          dialogView.frame = CGRectMake((screenSize.width - dialogSize.width) / 2, (screenSize.height - keyboardSize.height - dialogSize.height) / 2, dialogSize.width, dialogSize.height);                      }                      completion:nil      ]; }   - (void)keyboardWillHide: (NSNotification *)notification {     CGSize screenSize = [self countScreenSize];     CGSize dialogSize = [self countDialogSize];       [UIView animateWithDuration:0.2f delay:0.0 options:UIViewAnimationOptionTransitionNone                      animations:^{                          dialogView.frame = CGRectMake((screenSize.width - dialogSize.width) / 2, (screenSize.height - dialogSize.height) / 2, dialogSize.width, dialogSize.height);                      }                      completion:nil      ]; }   @end 調用代碼:     -(void)customShow{     CustomIOSAlertView *alertView = [[CustomIOSAlertView alloc] init];           [alertView setContainerView:[self customView]];           [alertView setButtonTitles:[NSMutableArray arrayWithObjects:@"取消", @"確定", nil]];     [alertView setDelegate:self];           [alertView setOnButtonTouchUpInside:^(CustomIOSAlertView *alertView, int buttonIndex) {         NSString *result=alertView.buttonTitles[buttonIndex];         NSLog(@"點擊了%@按鈕",result);         [alertView close];     }];           [alertView setUseMotionEffects:true];     [alertView show];   }   - (UIView *)customView {     UIView *customView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 240, 160)];           UILabel *tip=[[UILabel alloc]initWithFrame:CGRectMake(100, 10, 50, 30)];     [tip setText:@"提示"];     [customView addSubview:tip];                 UILabel *content=[[UILabel alloc]initWithFrame:CGRectMake(10, 60, 210, 30)];     [content setText:@"http://www.cnblogs.com/xiaofeixiang"];     [content setFont:[UIFont systemFontOfSize:12]];     [customView addSubview:content];     return customView; }