I have this task that I need to create a custom scrollable view with 3 different types of cells from scratch.(no UICollectionView nor UITableView)
I have no idea what is the best way to start. Wether I should subclass UIScrollview or ...
Any guidance or direction would be highly appreciated.
Create object of UIView, keep adding in UIScrollView depends on your array count.
Keep dynamic calculation for next UIView add subview in UIScrollView
Put transparent UIButton on UIView or use touch gesture to implement like didSelectedRowAtindex.
Another solution we can adapt when there is no UITableView.
Both TableView and Collection View inherits from UIScrollView. So using the parent class could be efficient. But inheritence also serves independent extensions it would also be ok to use the sub classes.
So, Decision depends on what you do. Here in your case.
If one of the cells include a text field for user entry, then scrollview could do better as it offers convienience to scroll/shrink/retain the current UI while showing all the content of UI even when keyboard is present.
If the cells only involve fields like labels,switches,indicators etc then tableview is the choice.
If the cells has non-consistent or non free flow sections then collection view could be better.
Related
When should I use which, and what are the disadvantages or disadvantages of each? I'm mainly confused with scrollview vs collectionview, I know tableview is limited to one column (I heard it gets messy when more than one column), but scrollview difference with collectionview seem the same to me.
Both CollectionView & TableView are basically subclasses of UIScrollView.But as compared to UIScrollView here you are provided with proper methods to provide your dataSource & delegates to handle operations user performs on data. Along with this you are provided predefined layout classes.
Now to choose between them completely depends on your UI Requirements. Suppose you want to display just a list of items with a simple UI go with TableView.If you want a custom Layout like a grid or like the one you see in Apple's photo's app CollectionView is the choice.
if you have a complex UI & you have no idea about Custom CollectionView layout classes go with scrollView.
Consider UITableView and UICollectionView first and if you cannot achieve the effect you want with them, try UIScrollView then. UIScrollView is more basic class. UITableView and UICollectionView have more delegate method for us.
If you want a list,UITableView would be better. And if you want a multicolumn,use UICollectionView.
I would like to customize the UICollectionView, but all the tutorials on the web and in books use UICollectionViewController which I do not want to use. I'm combining different kinds of UICollectionViews in the same UIViewController, so I don't want to limit myself by subclassing UICollectionViewController, which doesn't allow me to place several UICollectionViews in the same viewController along with other objects and labels.
How do I subclass UICollectionView? Specifically, what kinds of methods need to be overwritten? How do I layout what goes into it (i.e. where to put a text label, image, etc.)? I'm familiar with the data source / delegate protocols, but not quite sure how to customize the cell's look, placement of sub items within the cell, what classes need to be overwritten/sub classed, etc.
A list of things I need to do would be much appreciated!
Thanks!
You can do it like this link
Here are some good Examples to customize your collectionview.
Use WaterfallCollectionView from this. It may help you.
I believe that you don't need to sub-class UICollectionView but you need to sub-class UICollectionViewFlowLayout.
UICollectionViewFlowLayout is the object which manages the display of the collection view items and it is highly customizable.
I suggest you follow WWDC 2012:Advanced Collection Views and Building Custom Layouts
The best tutorial which worked for me was by Apple called Using the Flow Layout.
I think you wont have to subclass a collection view. What you would need instead is subclassing UICollectionViewLayout to customize the positioning of cells within the collection view. And if you are looking for a customized look of a cell, you would also have to subclass UICollectionViewCell and assign the sub classed cells to the Collection View.
The below links might help you,
https://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/CollectionViewPGforIOS/CreatingCustomLayouts/CreatingCustomLayouts.html
http://adoptioncurve.net/archives/2012/09/a-simple-uicollectionview-tutorial/
This is an Object Oriented Programming question:
So I am trying to build a UIView class that displays scatter plot. In my current implementation, I've created a datasource protocol that allows the chartView to ask for all the info it needs to plot the its data.
As it stands right now, when someone initializes the chartView and gives it a datasource, the chartview creates/manages several subviews: a 'dotsView' that displays all the data points, a scrollview to which the dotview is added (so it is scrollable), and a 'skeletonView' that sits in the background and displays other chart data like grid lines.
This system at first worked great, however, I decided that i'd like to animate changes to the points, and so i began to contemplate using a collectionView in lieu of the 'dotsView' placed within the scrollview since it'll handle the animation for me. However, as a collectionview would require a delegate, datasource, layout object, etc, all the sudden my chartView seems to looks more and more like a controller and not a view.
Now here is my question: Is it the wrong approach to allow a UIView to coordinate/configure other UIViews, even if those UIViews are a fundamental requirement of the whole? On the one hand, I'd love to preserve the simplicity of my chartView's public interface (initialize the view, give it a datasource, and you're done). On the other hand, this chartView is really not a view anymore, its more like a controller. But I don't want a consumer of my chart to think/treat it like a controller, I want them to use it as a view.
Any thoughts? I'd love to hear the insights of others.
Thanks!
It is totally fine for your ChartView to create a UICollectionView, use it as a subview, and be the data source and delegate for that subview, because the use of UICollectionView is an implementation detail of the ChartView.
Apple does this in UIPickerView. Under the covers, a picker view creates one table view for each component, and the picker view makes itself the data source and delegate for each table view. You can see in UIPickerView.h that it conforms to UITableViewDataSource. You can check that it conforms to UITableViewDelegate at runtime with +[NSObject conformsToProtocol:], or by using class-dump on the UIKit framework. Or you can just write a test app and poke around the view hierarchy. The debugger command po [[UIApp keyWindow] recursiveDescription] will get you started.
UIPickerView is the only view subclass in the iOS SDK that I know of that acts as the data source and delegate for its subviews, but many other UIKit view classes create and manage their own subviews. Examples:
UIScrollView has private subviews for its scroll indicators.
UITableView has private header, footer, section index, and row separator subviews.
UIButton has a private UILabel to display its text and a private UIImageView to display its image.
UISegmentedControl has private UILabel and UIImageView subviews.
UIProgressView uses several private UIImageView subviews to display its parts.
UISlider uses several private UIImageView subviews to display its parts.
UITextField uses private UIImageView subviews.
You answered you own question my friend: Is it the wrong approach to allow a UIView to coordinate/configure other UIViews -- YES!. Views should be casted by a Controller from an organizational stand point IMHO. I would build a Charting Controller that can cast out single and composite views and kill two birds with one stone. The you could route urls to the controller from Ajax to change the data represented in the chart
So Path uses this type of page where there is a view above their customized looking table that is a background photo, which contains some user info among other things. I'm trying to recreate something very similar to this.
So lets say that I hypothetically wanted to make a view that shows exactly the way the Path app does, but instead of that weird customized version of a table view that they have, there is an actual table. How would I do something like this? The reason why I would need there to be another UIScrollView embedded into the view is because the entire thing needs the capability to scroll. I'm trying to be as detailed as possible, but its a little difficult to explain.
What I'm imagining is going to happen if I just tried it right now, is that I'd embed a UIView above a UITableView within a UIScrollView that's the size of the frame, and when I'd go to scroll, the user would only scroll the UITableView, and not the entire thing at once. Hopefully that helps convey my doubts.
Another possibility is that I'm totally over thinking this, and I can simply just subclass a view in the header of a UITableView and it would stretch the width and height that I'd like. Hopefully this is the way as this would be easy!
Anyways, can anybody weigh in on this?
Path just uses a normal UITableView with UITableViewStyleGrouped.
The custom view at the top is the header of the first section of the table.
They also access the UIScrollViewDelegate method of the UITableView to change the look of the view (I think the image is moved) when the scroll view scrolls.
If you'd like a tableview that only scrolls within a part of the view and other stuff above it then you need to use a UIViewController. Then you can make it conform to UITableViewDelegate and UITableViewDatasource and add a UITableView and make the view controller the datasource and delegate.
Then you can also add a UIScrollView to it as well.
Ok, so I have a normal viewController that has a UIScrollView in it that gives details about distilleries. What I wanted to do was have a list of spirits that are distilled at the distillery that they are reading about. So I attempted to implement a UITableView inside of my UIScrollView, and after hooking everything up and writing all the delegate and datasource methods I come to find out that a UITableView will not work inside of a UIScrollView. So does anybody have any ideas as to what kind of User Interface Object I can use to accomplish something like a UITableView's dynamic characteristics? I don't want to use a UITextView because it just looks cheap and unstructured. I need something that can dynamically change the number of items shown because not all distilleries will have the same amount of spirits distilled there.
If you are implementing a UITableView, there is no need to create a UIScrollView.
As a UITableView will automatically increase its size and behave like a scrollable view whenever the content size is larger than the screen.