iOS透明viewControler

有时候在跳转控制器的时候需要，跳转到当前控制器上方，显示一个可以看到下方原来控制器的半透明控制器。

如下图：

跳转方式可以修改这句代码来实现，激变，从下往上。或者也可以自定义一些动画。（已经被我注释掉的那些）

controller.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;

跳转的时候根据要跳转到哪一层控制器上方的情况，修改如下代码

 [self.tabBarController presentViewController:controller animated:YES completion:nil] (这里是跳转到tabBar控制器的上方。)

第一个控制器代码

#import "ViewController.h"#import "MKDialogController.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.//    fade     //交叉淡化过渡(不支持过渡方向)//    push     //新视图把旧视图推出去//    moveIn   //新视图移到旧视图上面//    reveal   //将旧视图移开,显示下面的新视图//    cube     //立方体翻滚效果//    oglFlip  //上下左右翻转效果//    suckEffect   //收缩效果，如一块布被抽走(不支持过渡方向)//    rippleEffect //滴水效果(不支持过渡方向)//    pageCurl     //向上翻页效果//    pageUnCurl   //向下翻页效果//    cameraIrisHollowOpen  //相机镜头打开效果(不支持过渡方向)//    cameraIrisHollowClose //相机镜头关上效果(不支持过渡方向)}- (IBAction)btnClick:(UIButton *)sender {    MKDialogController *controller = [[MKDialogController alloc] init];    controller.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;    if ([[UIDevice currentDevice].systemVersion floatValue] >= 8.0) {        controller.providesPresentationContextTransitionStyle = YES;        controller.definesPresentationContext = YES;        controller.modalPresentationStyle = UIModalPresentationOverCurrentContext;//        CATransition *animation = [CATransition animation];//        animation.duration = 2.0;//        animation.timingFunction = UIViewAnimationCurveEaseInOut;//        animation.type = @"cameraIrisHollowOpen";////        animation.subtype = kCATransitionFromLeft;//        [self.view.window.layer addAnimation:animation forKey:nil];        [self.tabBarController presentViewController:controller animated:YES completion:nil];            } else {        self.view.window.rootViewController.modalPresentationStyle = UIModalPresentationCurrentContext;        [self presentViewController:controller animated:NO completion:nil];        self.view.window.rootViewController.modalPresentationStyle = UIModalPresentationFullScreen;    }}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end

要跳转的控制器代码

#import "MKDialogController.h"@interface MKDialogController ()@end@implementation MKDialogController- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view.    self.view.backgroundColor = [UIColor clearColor];    UIView *alphaView = [[UIView alloc] initWithFrame:self.view.frame];    UIView *baseView = [[UIView alloc] initWithFrame:self.view.frame];    alphaView.backgroundColor = [UIColor clearColor];    baseView.backgroundColor = [UIColor blackColor];    baseView.alpha = 0.8;    [self.view addSubview:baseView];    [self.view addSubview:alphaView];        UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];    button.frame = CGRectMake(20, 178, 100, 60);    [button setTitle:@"点我返回" forState:UIControlStateNormal];    button.backgroundColor = [UIColor brownColor];        [alphaView addSubview:button];    [button addTarget:self action:@selector(dissmiss) forControlEvents:UIControlEventTouchUpInside];}- (void)dissmiss{    [self dismissViewControllerAnimated:YES completion:nil];}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}/*#pragma mark - Navigation// In a storyboard-based application, you will often want to do a little preparation before navigation- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {    // Get the new view controller using [segue destinationViewController].    // Pass the selected object to the new view controller.}*/@end