3D 触摸与 Swift

iPhone 6s Plus 已经引入了 3D touch。这个新的界面层添加了两个行为：Peek 和 Pop。

简而言之，偷看和流行

偷看 - 努力

流行 - 真的很难

检查 3D 支持

你应该检查设备是否具有 3D 触摸支持。你可以通过检查 UITraitCollection 对象的 forceTouchCapability 属性的值来执行此操作。UITraitCollection 描述了应用程序的 iOS 界面环境。 **

if (traitCollection.forceTouchCapability == .Available) {    
    registerForPreviewingWithDelegate(self, sourceView: view)
}

实现委托

你需要在类中实现 UIViewControllerPreviewingDelegate 的两个方法。其中一种方法是偷看，另一种是流行为。

为窥视实现的方法是 previewingContext 。

func previewingContext(previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) -> UIViewController? {
    
    guard let indexPath = self.tableView.indexPathForRowAtPoint(location), cell = self.tableView.cellForRowAtIndexPath(indexPath) as? <YourTableViewCell> else {
        return nil
    }
    
    guard let datailVC = storyboard?.instantiateViewControllerWithIdentifier("<YourViewControllerIdentifier>") as? <YourViewController> else {
        return nil
    }

    datailVC.peekActive = true
    previewingContext.sourceRect = cell.frame

    // Do the stuff
    
    return datailVC

}

为 pop 实现的方法是 previewingContext 。 :)

func previewingContext(previewingContext: UIViewControllerPreviewing, commitViewController viewControllerToCommit: UIViewController) {

    let balanceViewController = viewControllerToCommit as! <YourViewController>

    // Do the stuff

    navigationController?.pushViewController(balanceViewController, animated: true)

}

如你所见，它们是重载方法。你可以以任何方式使用 3D touch 来实现这些方法。

Objective-C

//Checking for 3-D Touch availability
if ([self.traitCollection respondsToSelector:@selector(forceTouchCapability)] &&
        (self.traitCollection.forceTouchCapability == UIForceTouchCapabilityAvailable))
    {
        [self registerForPreviewingWithDelegate:self sourceView:self.view];
    }
//Peek
- (UIViewController *)previewingContext:(id<UIViewControllerPreviewing>)previewingContext
              viewControllerForLocation:(CGPoint)location {

    NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:location];
    Country *country = [self countryForIndexPath:indexPath];
    if (country) {
        CountryCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
        if (cell) {
            previewingContext.sourceRect = cell.frame;
            UINavigationController *navController = [self.storyboard instantiateViewControllerWithIdentifier:@"UYLCountryNavController"];
            [self configureNavigationController:navController withCountry:country];
            return navController;
        }
    }
    return nil;
}
//Pop
- (void)previewingContext:(id<UIViewControllerPreviewing>)previewingContext commitViewController:(UIViewController *)viewControllerToCommit {
    
    [self showDetailViewController:viewControllerToCommit sender:self];
}