# VTMagic

VTMagic is a page container library for iOS, you can custom every page controller by different identifier if you need. It's so easy to use!（[中文手册传送门](http://www.jianshu.com/p/cb2edb21055f)）

[CHANGELOG][CHANGELOG_EN]\([变更日志][CHANGELOG_CN])

![preview image](Gif/magic.gif)


## Communication
- If you **found a bug**, *and can provide steps to reliably reproduce it*, open an issue.
- If you **have a feature request**, open an issue.
- If you **want to contribute**, submit a pull request.


## Installation

### CocoaPods

VTMagic is available through [CocoaPods](http://cocoapods.org). To install
it, simply add the following line to your Podfile, and then import <VTMagic/VTMagic.h>:

```ruby
pod "VTMagic"
```

### Manually

1. Download the project and drop `VTMagic` folder into your project.
2. Import file `VTMagic.h`.

```objective-c
#import "VTMagic.h"
```

## Requirements

This library requires iOS 6.0+ and Xcode 7.0+.

## Usage

To run the example project, clone the repo, and run `pod install` from the project directory first.

### Integration

```objective-c
- (void)viewDidLoad {
    [super viewDidLoad];

    [self addChildViewController:self.magicController];
    [self.view addSubview:_magicController.view];

    [_magicController.magicView reloadData];
}

- (VTMagicController *)magicController {
    if (!_magicController) {
        _magicController = [[VTMagicController alloc] init];
        _magicController.magicView.navigationColor = [UIColor whiteColor];
        _magicController.magicView.sliderColor = [UIColor redColor];
        _magicController.magicView.layoutStyle = VTLayoutStyleDivide;
        _magicController.magicView.switchStyle = VTSwitchStyleDefault;
        _magicController.magicView.navigationHeight = 40.f;
        _magicController.magicView.dataSource = self;
        _magicController.magicView.delegate = self;
    }
    return _magicController;
}
```
or like this
```objective-c
#import "VTMagicController.h"

@interface ViewController : VTMagicController

@end
```

```objective-c
@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.magicView.navigationColor = [UIColor whiteColor];
    self.magicView.sliderColor = [UIColor redColor];
    self.magicView.layoutStyle = VTLayoutStyleDefault;
    self.magicView.switchStyle = VTSwitchStyleDefault;
    self.magicView.navigationHeight = 40.f;
    self.magicView.dataSource = self;
    self.magicView.delegate = self;
    
    [self.magicView reloadData];
}
```

### Protocols

You must conform to `<VTMagicViewDataSource>`. `<VTMagicViewDelegate>` and `<VTMagicReuseProtocol>` are optional.

####  VTMagicViewDataSource

```objective-c
- (NSArray<NSString *> *)menuTitlesForMagicView:(VTMagicView *)magicView {
    return _menuList;
}

- (UIButton *)magicView:(VTMagicView *)magicView menuItemAtIndex:(NSUInteger)itemIndex {
    static NSString *itemIdentifier = @"itemIdentifier";
    UIButton *menuItem = [magicView dequeueReusableItemWithIdentifier:itemIdentifier];
    if (!menuItem) {
        menuItem = [UIButton buttonWithType:UIButtonTypeCustom];
        [menuItem setTitleColor:RGBCOLOR(50, 50, 50) forState:UIControlStateNormal];
        [menuItem setTitleColor:RGBCOLOR(169, 37, 37) forState:UIControlStateSelected];
        menuItem.titleLabel.font = [UIFont fontWithName:@"Helvetica" size:16.f];
    }
    return menuItem;
}

- (UIViewController *)magicView:(VTMagicView *)magicView viewControllerAtPage:(NSUInteger)pageIndex {
    if (0 == pageIndex) {
        static NSString *recomId = @"recom.identifier";
        VTRecomViewController *recomViewController = [magicView dequeueReusablePageWithIdentifier:recomId];
        if (!recomViewController) {
            recomViewController = [[VTRecomViewController alloc] init];
        }
        return recomViewController;
    }

    static NSString *gridId = @"grid.identifier";
    VTGridViewController *gridViewController = [magicView dequeueReusablePageWithIdentifier:gridId];
    if (!gridViewController) {
        gridViewController = [[VTGridViewController alloc] init];
    }
    return gridViewController;
}
```

#### VTMagicViewDelegate

```objective-c
- (void)magicView:(VTMagicView *)magicView viewDidAppear:(UIViewController *)viewController atPage:(NSUInteger)pageIndex {
    NSLog(@"pageIndex:%ld viewDidAppear:%@", (long)pageIndex, viewController.view);
}

- (void)magicView:(VTMagicView *)magicView viewDidDisappear:(UIViewController *)viewController atPage:(NSUInteger)pageIndex {
    NSLog(@"pageIndex:%ld viewDidDisappear:%@", (long)pageIndex, viewController.view);
}

- (void)magicView:(VTMagicView *)magicView didSelectItemAtIndex:(NSUInteger)itemIndex {
    NSLog(@"didSelectItemAtIndex:%ld", (long)itemIndex);
}
```

#### VTMagicReuseProtocol

This method will be called when page is reused, you should clear old data or reset content offset in here.

```objective-c
- (void)vtm_prepareForReuse {
    NSLog(@"clear old data if needed:%@", self);
}
```

## Features

#### Appearance callbacks

VTMagic will automatically calls the appearance callbacks when user switches the page, maybe you should do something in here, e.g. refresh page info.

```objective-c
- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];

    // do something...
}

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];
    
    // do something...
}

```

#### Get magicController

You can get the nearest magicController in any child view controller which is conforms to `<VTMagicProtocol>`, after you import file `VTMagic.h`.

```objective-c
NSInteger currentPage = self.magicController.currentPage;
UIViewController *viewController = self.magicController.currentViewController;
```

#### Switch to specified page

You can switch to some specified page.

```objective-c
[self.magicView switchToPage:3 animated:YES];
[self.magicController switchToPage:3 animated:YES];
```
#### Get specified view controller

You can get any page controller by page index, it will return nil if the page is not on the screen.

```objective-c
UIViewController *viewController = [self.magicView viewControllerAtPage:3];
UIViewController *viewController = [self.magicController viewControllerAtPage:3];
```


## Author

**VictorTian** *email: tianzhuo112@163.com*


## License

VTMagic is released under the MIT license. See LICENSE for details.



<!-- external links -->

[CHANGELOG_CN]: CHANGELOG_CN.md
[CHANGELOG_EN]: CHANGELOG_EN.md