Overlapping Views And Gesturerecognizer Iphone

In your custom transition animation, you may have control of both the outgoing view con‐ troller's view and the incoming view controller's view. Moreover, you are free to add further momentary views in the course of the course of the animation. For example, because the out‐ going view departs and the incoming view arrives, a 3rd view can move throughout from the outgoing view to the incoming view. This might be a method so that you can counsel or emphasize the significance of the transition that's now going down. As you ponder what could be possible and how it could be achieved, don't neglect about view snapshotting . Instead of transferring a view, which could upset the association of issues, you'll find a way to take a snapshot of that view and transfer the snapshot. In addition, a custom animation may be interactively gesture-driven (similar to the finest way a navigation controller's view can be popped, in iOS 7, by dragging from the left fringe of the screen). The consumer does not merely tap and cause an animation to take place; the consumer performs an prolonged gesture and progressively summons the brand new view to supersede the old one. The user can thus take part within the progress of the transition. See the dialogue earlier on this chapter of how a view controller's view is resized to fit the interface. In iOS 7, a tab bar controller's child controller's view by default will underlap the tab bar if the tab bar is translucent. The root view controller is answerable for rotation of the interface. The consumer can rotate the system, and also you would possibly like the interface to rotate in response, to compensate.

As I defined in Chapter 1, the window is successfully pinned to the bodily show , but a view could be given a remodel in order that its high moves to the current high of the display. The root view controller can reply to gadget rotation by making use of this transform to the root view. The root view controller additionally bears ultimate duty for manipulation of the status bar. View controllers do many issues mechanically, however the choices that specify the details are as a lot as you. The root view controller rotates the interface in response to the user's rotation of the system; but should it achieve this on this particular occasion? A sure transition between views of built-in view controllers could come with a selection of builtin animations; which one would you like? (Or, in iOS 7, do you prefer to produce your personal animation?) Similarly, some view controllers add navigation interface to their views; how ought to that interface look? You'll decide all of this, and extra, through your customization of view controllers. One further bit of configuration, if you're using the page curl transition, is carried out through the doubleSided property. If it is YES, the next page occupies the back of the earlier web page. The default is NO, except the spine is in the center, during which case it's YES and can't be modified. A web page view controller in a storyboard allows you to configure its transition fashion, navigation orientation, and spine location. It additionally has delegate and knowledge supply retailers, though you're not allowed to attach them to other view controllers (you can't draw an outlet from one scene to another in a storyboard). The transition uses the flip horizontal animation belonging to the presenting view con‐ troller, rather than the quilt vertical animation of the introduced view controller. It's helpful to experiment with the above code, commenting out particular person lines to see what impact they have on the overall outcome. Note too that all the properties mentioned in this part could be set by method of the nib editor. There is, nonetheless, another presentation fashion that works on the iPhone — UIModalPresentationCustom. Its use has to do with customized transition animations, which I'll discuss later on this chapter.

When a view controller is presented, and its presentation type just isn't UIModalPresentationFullScreen, a question arises of whether its standing bar methods must be consulted. By default, the reply is no, as a outcome of this view controller just isn't changing into the top-level view controller, supplanting the basis view controller. To make the reply be yes, set this view controller's modalPresentationCapturesStatusBarAppearance to YES. Sure sufficient, there's our green background and our "Hello, world" label! We have proved that we can create a view controller and get its view into the interface. But maybe you're not persuaded that the view controller is managing that view in an attention-grabbing means. While our app is working in the simulator, choose Hardware → Rotate Left or Hardware → Rotate Right. We have been cautious to give the label an appropriate autoresizingMask, to keep it centered within the view even when the view's bounds are changed to fit the rotated window. When we created our view controller's view (self.view), we never gave it an affordable frame. This is as a outcome of we're relying on another person to border the view appropriately. In general, it's the duty of whoever puts a view controller's view into the interface to offer the view the proper body — and this can by no means be the view controller itself. This a half of the guide is about view controllers, and about all the various kinds of view supplied by the Cocoa framework — the built-in "widgets" with which you'll assemble an app's interface. • Chapter 6 is about view controllers, the elemental iOS mechanism for allowing a complete interface to get replaced by one other. Every app you write could have its interface managed by at least one view controller. • Chapter 7 is about scroll views, the iOS mechanism for letting the consumer scroll and zoom the interface. • Chapter 8 explains desk views, a kind of scroll view that lets the user navigate via any quantity of knowledge, together with collection views, a generalization of desk views. • Chapter 9 is about two types of interface distinctive to, and attribute of, the iPad — popovers and split views. • Chapter 10 describes several ways of presenting textual content in an app's interface — labels, text fields, text views, and text drawn instantly. A net view is an easy-to-use interface widget backed by the power of a full-fledged net browser.

• Chapter 12 describes all of the remaining built-in iOS interface widgets. • Chapter 13 is concerning the forms of modal dialog that may appear in entrance of an app's interface. A collection view in my Latin flashcard app The collection view format can place its components wherever it likes. To get you started, there's a built-in UICollectionView‐ Layout subclass — UICollectionViewFlowLayout. UICollectionViewFlowLayout arranges its cells in something like a grid. The grid may be scrolled both horizontally or vertically, so this grid is a sequence of rows or columns. It defines two supplementary view sorts, using them to let you give every part a header and a footer. Figure 8-11 reveals a group view, laid out with a circulate layout, from my Latin flashcard app. This interface simply lists the chapters and lessons into which the flashcards them‐ selves are divided, and permits the consumer to leap to a desired lesson by tapping it. Previ‐ ously, I was using a table view to present this record; when collection views were introduced , I adopted one for this interface, and you can see why. So a collection view is a a lot more compact and acceptable approach to current this interface than a table view. If UICollectionViewFlowLayout doesn't fairly meet your needs, you can subclass it, or you can subclass UICollectionViewLayout itself. Setting the view controller's title property units the title of the navigationItem mechanically, and is usually one of the best approach. The titleView can be any sort of UIView; if set, will most likely be displayed as a substitute of the title. The titleView can implement additional UIView performance; for example, it can be tappable. Even in case you are utilizing a titleView, you should nonetheless give your view controller a title, as will in all probability be wanted for the back button when a view controller is pushed onto the stack on high of this one. Figure 6-1 exhibits the TidBITS News master view, with the navigation bar displaying a titleView which is a image view; the master view's title is subsequently not displayed.

Figure 6-5, from my Latin flashcard app, is one other instance of a offered view. It has a Cancel button, and the consumer is in a special "mode", performing a drill exercise rather than scrolling via flashcards. Nevertheless, the "modal" characterization is not all the time apt. A introduced view controller might be no more than a device that you just, the programmer, have used to change the inter‐ face; the person needn't be acutely aware of this. With the coming of the iPad, the range of what a presented view controller's view could do was extended. A presented view on the iPad, instead of replacing the whole interface, can replace a subview throughout the present interface. Alternatively, a introduced view con‐ troller's view on the iPad might cowl the prevailing interface only partially; the existing interface is rarely removed. And iOS 7 provides you a approach to accomplish the same factor on the iPhone. Content is scrolled and zoomed, and you may set up a gesture recognizer on it, to detect gestures not intended for the net view itself. Like a text view , its dataDetectorTypes property allows you to set certain kinds of data to be automatically transformed to tappable links. It is feasible to design a whole app that's effectively nothing however a UIWebView — particularly in case you have management of the server with which the consumer is interacting.

Indeed, earlier than the appearance of iOS, an iPhone app was a web application. There are nonetheless iPhone apps that work this fashion, but such an strategy to app design is outside the scope of this book. A web view's most essential task is to render HTML content material; like all browser, an online view understands HTML, CSS, and JavaScript. In order to construct content for an online view, you should know HTML, CSS, and JavaScript. Discussion of these languages is beyond the scope of this e-book; every would require a guide of its personal. The factor to bear in mind is that you have to use a web view to display content material that isn't fetched from the Internet or that isn't clearly an online web page. WebKit is a robust layout engine; HTML and CSS are how you tell it what to do. Game, I current the Help documentation in a UIWebView simply because it's so convenient for laying out styled text with footage. Autoresizing Autoresizing is the pre-iOS 6 way of performing structure automatically. A subview will respond to its superview's being resized, in accordance with the foundations prescribed by the subview's autoresizingMask property value. Autolayout Autolayout, launched in iOS 6 , depends on the constraints of views. A constraint is a full-fledged object with numeric values; it is rather more sophisticated, descriptive, and powerful than the autoresizingMask. Many constraints can apply to a view, they usually can describe a relationship between any two views . Autolayout is implemented behind the scenes in layoutSubviews; in impact, constraints permit you to write sophisticated layoutSubviews performance without code.

The want for guide structure is rare, but it's there when you need it. Autoresizing is used automatically until you delib‐ erately flip it off by setting a superview's autoresizesSubviews property to NO, or except a view makes use of autolayout as a substitute. One of the chief places the place you opt in to autolayout is the nib file, and in Xcode 5 all new .storyboard and .xib files do opt in — they've autolayout turned on, by default. To see this, select the file in the Project navigator, present the File inspector, and examine the "Use Auto Layout" checkbox. On the opposite hand, a view that your code creates and adds to the interface, by default, uses autoresizing, not autolayout. If a nib's "Use Auto Layout" is checked, don't load it on any system sooner than iOS 6. If you do, your app will crash, as a outcome of you're us‐ ing a class, NSLayoutConstraint, that doesn't exist before iOS 6. Dynamic attributes The collection view is inserting or eradicating elements. It asks for the structure attributes that a component, specified by index path, should have before insertion or after removing. The assortment view can thus animate between the element's static attributes and these dynamic attributes. For instance, if an element's lay‐ out attributes alpha is zero after elimination, the element will appear to fade away as it's removed. The assortment view additionally notifies the format of pending modifications via some strategies whose names begin with prepare and finalize. This is one other means for the layout to take part in animations, or to carry out other kinds of preparation and cleanup. UICollectionViewLayout is an summary class; to make use of it, you have to subclass it, or begin with the built-in subclass, UICollectionViewFlowLayout. UICollectionViewFlowLayout A concrete subclass of UICollectionViewLayout; you need to use it as is, or you'll be able to subclass it. It lays out objects in a grid that can be scrolled both horizontally or vertically, and it defines two supplementary element varieties to serve as the header and footer of a bit. A flow format has a scroll path, a sectionInset , an itemSize together with a minimumInteritemSpacing and minimumLineSpacing, and a headerReferenceSize and footerReferenceSize.

At a minimum, if you need to see any section headers, you must assign the move structure a headerReferenceSize, because the default is . Otherwise, you get initial defaults that can a minimal of permit you to see one thing instantly, similar to an itemSize of and affordable default spacing between items and features. Be consistent There are multiple data source strategies, and you cannot know which one will be called at a given second. So you should ensure your responses are mutually constant at any second. For example, a common beginner error is forgetting to take into account, in your information source strategies, the likelihood that the information may not but be prepared. This might sound daunting, but you'll be fine so lengthy as you keep an dependable adherence to the principles of model–view–controller. How and if you accumulate the precise information, and the way that knowledge is structured, is a mannequin concern. You'll need to design the mannequin in such a way that the controller can access any desired piece of knowledge roughly immediately. This isn't normally a reason for any actual difficulty, as a result of the thing serving as knowledge supply will most likely also be the thing serving as delegate. Nevertheless, it is quite inconvenient when you're consulting the documen‐ tation; you'll probably wish to hold the info source and delegate documentation pages open concurrently as you work. If a desk view's contents are known beforehand, you'll have the ability to alternative‐ ly design the whole desk, together with the contents of particular person cells, in a storyboard. Given the in depth animation sources of iOS 7 , this is a superb likelihood so that you just can present your app with variety, curiosity, and distinctiveness. The workaround in our instance situation is to disable person interplay on the overlaying view and add a custom UIGestureRecognizer subclass to the scroll view. Set the customized recognizer to solely enable Stylus enter, then set the scroll view's pan gesture recognizer to only allow Direct and Indirect. Then your custom recognizer can ahead all of the contact occasions on to the overlaying view. As long as your own views are built to anticipate forwarded occasions it is safe to do so (you simply cannot do it with built-in UIKit views). But the view controller that presents the action sheet won't have ready access to the popover controller in order to set its passthroughViews! This whole state of affairs is simply one other maddening consequence of iOS's poor built-in popover management. A modal dialog demands attention; whereas it's present, the consumer can do nothing aside from work inside it or dismiss it. You might need to put up a easy modal dialog so as to give the person some info or to ask the consumer how to proceed.

Two UIView subclasses, UIAlertView and UIActionSheet, assemble and current rudimentary modal dialogs. One sees often a misuse of the built-in dialogs to include further interface. For example, a UIActionSheet is a UIView, so in concept you'll have the ability to add a subview to it. I can't recommend such habits; it clearly isn't supposed, and there's no want for it. If what you want isn't what a built-in dialog usually does, don't use a built-in dialog. A native notification is an alert that the system presents at a predetermined time on your app's behalf when your app isn't frontmost. This alert can generate a UIAlertView, so I talk about it on this chapter as properly. An activity view is a modal dialog displaying icons representing attainable courses of action, and intended in sure circumstances to replace the motion sheet. If you've older app code in which you have been manually setting the body of a view controller's view, in code, to [ applicationFrame] in iOS 6 or earlier than, don't try this in iOS 7. In iOS 7, permit the run‐ time to resize your view controller's view routinely. As is clear from the above code, use is made of these settings through the attribute modification course of.

It's stunning how popular this part is in most of the apps that we use daily. We can add the desk view controller directly to the Storyboard by dropping it on an empty area. In order to add it to an existing view, we will use a Container View. Control+click the Container View, drag the arrow to the desk view controller, and choose the "Embed" Segue. Since within the demo we use static data to populate the desk view, we set the property "Content" to be "Static Cells" . Every cell within the desk may be customized, adding photographs, buttons or another sort of elements. If a view controller is displaying an occasion in the database and the database is deleted while the person is viewing it, the delegate will get the identical notification as if the consumer had deleted it. The Web Inspector inspects an app running within the Simulator viewport can change when the app rotates. Setting the initial-scale causes the view‐ port size to adopt appropriate values in both orientations. For example, you might have one CSS file that lays out your web view's content material on an iPhone, and another that lays it out on an iPad. Inspecting, debugging, and experimenting with UIWebView content material is significantly eased by the Web Inspector, built into Safari 6.1 and later. It can see a web view in your app running in the Simulator, and lets you analyze each side of how it works. For instance, in Figure 11-3, I'm inspecting an image to see how it is sized and scaled. Two popovers • Both views proceed to seem side by side; the second view is narrower than it is in landscape orientation, as a outcome of the display is narrower. • Only the second view appears, with an choice to summon the primary view by tapping a bar button item .