How To Replace Listview With Recyclerview

One of the reasons is that RecyclerView has a more extensible framework, especially since it provides the ability to implement both. My question is: should I change my list to a RecyclerView even though the list is very limited in size, since every item is fully created by manual user's input?. 处理Change动画。 一、两者的缓存机制上的区别 先来说一样的地方,ListView与RecyclerView缓存机制原理大致一样,滑动的时候. - CursorRecyclerAdapter. We can handle this issue by using a RecyclerView RecyclerView is similar to ListView, but it is more smart about heap memory. Android apps using Listview for implementing newsfeed or contact lists will likely face performance issues or unnecessary lags when the user scrolls the view fast. RecyclerView is about performance and display enhancements over widgets like ListView. The views in the RecyclerView of a class we define by RecyclerView. Here is my situation. Then, let's say that you load your images in your RecyclerView. In this post we are going to look at an existing app that uses a ListView. Recyclerview is game changer for android developer. If you're looking for a more modern approach, then check out the CSS Table Gradient example below. This example show how to add/remove items to/from custom ListView, using Java code at run-time. So I found a great way to change the color dynamically for things like the new cards feature on Material Design. To use the RecyclerView widget, you have to specify: an Adapter: extend the RecyclerView. The most popular methods are to use a ListView or a Recycler View. Combining it with CardView, cloning Gmail inbox, adding Swipe to delete functionality and bunch of other. To connect data with View items, the adapter needs to know about the View items. The getRating() method of android RatingBar class returns the rating number. It is mandatory. Check out CamelPhat on Beatport. A previous tutorial described implementing RecyclerView. For the new RecyclerView Google has decided to replace the old Adapter interface with a new RecyclerView. Let's see a simple example to start, stop and pause the audio play. Previously I had been passing my Listview through a method that would use a cursor and SimpleCursorAdapter to populate the TextViews in my CardView (as seen above). Like its predecessors, RecyclerView is designed to display a large data set in a small window, but RecyclerView offers more layout options and is better optimized for displaying large collections. RecyclerView and CardView Android Lollipop introduces a new UI widget called RecyclerView. HeaderListView is a list view with sections and with a cool iOS-like "sticky" section headers. RecyclerView overview. In that case, dx and dy will be 0. to use RecyclerView instead of listview. There are some cases where the ListView is still the better choice. This method returns the ListView widget which will then be added to the body of the Scaffold we created earlier. We also have to call scrollToPosition(0) on the RecyclerView to ensure that the user can always see all items when searching for something. 8 is last update for Amir_RecyclerView and we will work on AX_RecyclerView only in future. RecyclerView is works just like listview but more well organised, felexible to customize and optimize to work and in rendering the view of large data set. When user scroll from left to right at the beginning of RecyclerView, it will […]. One of the highlights of the 6. RecyclerView is definitely more extensible. As FloatingActionButton extends ImageView, you’ll use android:src or any of the methods such as setImageDrawable() to control the icon shown within the FloatingActionButton. In Android, RecyclerView is an advanced and flexible version of ListView and GridView. 1 (API level 25) For more on Android, watch our tutorial Outputting Data to Your. xml for grid item of RecyclerView and paste the following code in it. You can use the RecyclerView widget when you have data collections whose elements changes at runtime based on user action. Recycler View allows to display thousands rows data with optimized memory usage. Also, we now know the need of layout managers and how they can be used to change the look of the recycler layout as well as how adapter works internally to recycle, reuse views and bind data as per the. When your ListView is connected to an adapter, the adapter will instantiate rows until the ListView has been fully populated with enough items to fill the full height of the screen. There are one TextView and two Buttons in above screen. Whereas RecyclerView supports three types of lists using RecyclerView. Forms so I did a search and found the following :-. The input to the adapter of an recycler view can be any arbitrary Java objects. all i want to do is update 1 row at a given time when user like the empty heart i need to change that imageview image to a filled heart image. Contribute to yefengjie/HiRecyclerView development by creating an account on GitHub. Start the new project. In this step we create a new xml file for item row in which we creates a TextView and ImageView to show the data in grid format. …There are some cases where. While the Android ListView widget provided a lot of convenience when displaying a set of data, it did so at great cost to efficiency. I'm using ViewStub in this tut Link. Create RecyclerView application. Of course, you can use this pattern together with a ListView, but it is optional. Create a new layout file called ‘property_layout’, and add RelativeLayout as the root tag. But day by day the RecyclerView took the whole stage and there was almost nothing left for the old ListView. Today we are going to make our RecyclerView’s items clickable, which was a trivial task with ListView. This tutorial will cover some important aspects of Android RecyclerView giving all the information you need to build a great Android app using it. ” It has a lot of features you might otherwise spend quite a while. and can make ListView as you require. It’s a lot of data — 17. Android applications. In this example, we show you how to display a list of fruit name via ListView, it should be easy and self-explanatory. In this article we will see how to make Image Slider with ViewPager on android platform. In the designer scroll down the Palette until you can see the Contaners and place a ListView on the design surface. Rather than try and determine the exact number of pixels that it needs to scroll through before reaching the end point, it performs a series of 10000 pixel flings at a speed of 25 milliseconds per inch until the end target item comes in to the viewport, and then it decelerates to stop with the end target visible. If you use < DataSnapshot. Supported React Native Versions. Prepare your project. I love an Activity that can be dismissed via a drag. In each ListView item, I put a button inside so when user clicks on the button, the app will play a voice over according to the text in that ListView item. Xamarin has built-in support for the MVVM pattern including data binding, making it easy to follow this design pattern so that you can create application code that's better tested and easier to extend without requiring radical changes. It is in the Android SDK since the API 1. Nowadays, for this purpose, we should use a RecyclerView because basically, it’s more flexible and efficient than a ListView. This view will be part of the support library, so it is backward compatible till API level 7. Check out CamelPhat on Beatport. recyclerview selected item, recyclerview, recyclerview android, recyclerview select, android listview highlight selected item, android login show in recyclerview, android recyclerview, highlight. The RecyclerView widget is a more advanced and flexible version of ListView. ListView supports only simple linear list view with vertical scrolling. This widget is a container for displaying large data sets that can be scrolled very efficiently by maintaining a limited number of views. The RecyclerView widget is a more advanced and flexible version of ListView. The user sees a list of items and can scroll through them. Now with Filters and updated doc. First, define a stock RecyclerView in a layout file and inflate it in an Activity/Fragment. Create a activity layout with RecyclerView. It shows displays data like list view but unlike list view it only initializes the number of item view that could be displayed on screen with 2–3 extra margin of item. Question: "I have code which I used to check duplication in a ListView, but it doesn't seem to be working. Handling Item-Click Events. There are few third party libraries that exist to help implement drag and drop in RecyclerView and Paul Burke provided an excellent three part tutorial on how to use native components […]. If you’ve used a RecyclerView, you may know that they don’t have a setOnItemClickListener as ListView had, so we have to create our own way to do it. Staggered GridView Staggered GridView is nothing but GridView with random grid sizes that look nice in app. drag and change position of item in recyclerview. Fragments represent multiple screen inside one activity. A RecyclerView can be thought of as a combination of a ListView and a GridView. How to change Spinner text color in Android. There are few third party libraries that exist to help implement drag and drop in RecyclerView and Paul Burke provided an excellent three part tutorial on how to use native components […]. The RecyclerView widget is an integral part of most Android applications today. In this horizontal listview android example, we will discuss how to create a horizontal listview using RecyclerView. Okay maybe we just go to the topic that is showing all data from firebase database to recyclerview then do update on time with firebase, and why we using recyclerview? 'cause recyclerView was designed to replace the ListView, and it does this very well. There are three key benefits of using a CursorLoader: The query is handled on a background thread for you (courtesy of being built on AsyncTaskLoader) so that large data queries do not block the UI. order to help them achieve their dreams and change. Use the RecyclerView widget when you have data collections whose elements change at runtime based on user action or network events. Notice that HeaderListView is not a subclass of Android's ListView but uses composition. This significantly increases the performance. The SwipeRefreshLayout sample at support4demo running is ok,but when i use SwipeRefreshLayout to my listview ,and use BucketListAdapter for the adapter. RecyclerView is about performance and display enhancements over widgets like ListView. A method is provided to obtain a list iterator that starts at a specified position in the list. The answer is no, no it did not. while the listview scrolling up ,the listview top view canit scroll down again,why? is the SwipeRefreshLayout ‘s bug?(sorry,my english is not very well),thanks. In my next post, I'll cover more than just display. How to create a RecyclerView. I was wondering if there's an easy way to convert a ListView adapter to a RecyclerView adapter and hence listview to RecyclerView. By continuing to browse this site, you agree to this use. In the RecyclerView several different components work together to display data. It's new, efficient and highly customisable, no wonder everyone wants to make the switch. 2 Preview includes a new layout editor that's specially-built for a new layout called ConstraintLayout. It addresses several issues were encountered with the older components, and it makes you follow a well-structured programming style. Most of time ListView and RecyclerView are used to show uniform item view, such as a simple text…. Create RecyclerView application. In this horizontal listview android example, we will discuss how to create a horizontal listview using RecyclerView. The capacity is the size of the array used to store the elements in the list. Today, in this article we are going to learn how to add search filter functionality to RecyclerView. Parent is visible by default but the child view has to be. Following are some of the steps used to implement simple ListView using array adapter. To implement a ListView, we have to create the following:. In getView () method of our Adapter we inflate the item layout xml file and then give the reference of every view by using the unique id’s we provide in our xml file. While the Android ListView widget provided a lot of convenience when displaying a set of data, it did so at great cost to efficiency. Modify from last example of Custom ListView with ImageView. RecyclerView requires that we provide an adapter derived from RecyclerView. In this tutorial, we will create a simple Android app to display a list of data, and switch display mode between Listview and Gridview in Android at runtime. Also, we now know the need of layout managers and how they can be used to change the look of the recycler layout as well as how adapter works internally to recycle, reuse views and bind data as per the. RecyclerView`: A newer Android ViewGroup object meant to render any adapter-based View. So when we insert many videos or images in youer app, I’m sure “Out of Memory(OOM)” happens. It is important to know how to use it and how to customize its behavior. #The Problem In the way of replacing ListViews with RecyclerView I hit this obstacle where there is no onItemClickListener in RecyclerView ??? And when googled, I found almost all the posts saying we have to implement this using the GestureDetector. In this case, use this method to help increase performance of the display when size of the RecyclerView is not going to change - even though the rows/items will come and go dynamically. Use the RecyclerView widget when you have data collections whose elements change at runtime based on user action or network events. For example, the alternate view could contain a screenshot of how the RecyclerView would look with data. If you use Gradle, add to your dependencies: compile 'com. Assign an id to the view that holds the item cell Get the view just the way you have for the textviews set an onClick to the root inside the method like this:. However, in a RecyclerView, there are features that separate your code into maintainable components even as they enforce memory-efficient design patterns. So, there are 3 touchable(2 Buttons and the rest of the space in a row) views that will react to clicking events. Let’s talk about RecyclerView! This is a very important design element for Android and almost every application should implement it. In the designer scroll down the Palette until you can see the Contaners and place a ListView on the design surface. You still have to know how the ListView/RecyclerView work to get the results. Nowadays, for this purpose, we should use a RecyclerView because basically, it's more flexible and efficient than a ListView. The issue at hand. The CardView widget, on the other hand, is a new component that does not “upgrade” an existing component. In Android, RecyclerView is an advanced and flexible version of ListView and GridView. Okay maybe we just go to the topic that is showing all data from firebase database to recyclerview then do update on time with firebase, and why we using recyclerview? 'cause recyclerView was designed to replace the ListView, and it does this very well. There doesn't seem to be anything out of the box yet in Xamarin. RecyclerView can do all works performed by ListView. Whenever you are working with a RecyclerView. How do I convert my ListView adapter into RecyclerView adapter? I am currently using a listview instead of a RecyclerView for my data. Whenever we need to refresh the content's of a view via a vertical swipe gesture we use Pull To Refresh. If you haven’t read part 1 I recommend you to do it. Assign an id to the view that holds the item cell Get the view just the way you have for the textviews set an onClick to the root inside the method like this:. But with complex list of data Listview not provide good performance as it not reuse cell (Recycle) while scrolling up/down (We can achieve this using Viewholder concept in Listview). This widget is a container for large sets of views that can be recycled and scrolled very efficiently. In this example, we will see how to create a simple expandable list view using Android’s ExpandableListView widget. As the name suggests, Android RecyclerView is used to reuse cells when scrolling up and down by recycling the items in the list. What is RecyclerView? -> The RecyclerView widget is a more advanced and flexible version of ListView. Start the new project. * If your use of RecyclerView falls into this category, set this to {@code true}. With the new Android L release a new View called RecyclerView will be introduced. Full Description that how to make a swipe to delete listview in android. Kotlin compiler produces byte-code, thus there really is no difference in terms of look and feel of Kotlin applications versus those written in Java. Clear() and this is what is causing it. Android ListView with Custom Adapter Example Tutorial Anupam Chugh 39 Comments In this tutorial we’ll use a CustomAdapter that populates the custom rows of the Android ListView with an ArrayList. What is RecyclerView. Here is an example for both yelloy and blue colours. Previously I had been passing my Listview through a method that would use a cursor and SimpleCursorAdapter to populate the TextViews in my CardView (as seen above). Use the RecyclerView widget when you have data collections whose elements change at runtime based on user action or network events. …The answer is no, no it did not. Did you understand anything? At least I did not. Today we are going to learn how to add search functionality to ListView, GridView and RecyclerView. Nevertheless, studying ListView still has it's benefits: You can gain insights into why RecyclerView works the way it does; You may run into ListView in legacy code, and it's best to know how to work with it ; By working through this tutorial, you'll become familiar with ListView, and you'll do so by creating a recipe list app. The RecyclerView widget is a more advanced and flexible version of ListView. The RecyclerView widget is a more advanced and flexible version of ListView. It is supposed to be the successor of ListView and GridView. The RecyclerView in Android is an advanced version of ListView. LayoutManager. java Let's write the code to start, pause and stop the audio player. Android RecyclerView is a more advanced version of ListView with improved performance and other benefits. In a ListView, it was recommended to use the ViewHolder pattern but it was never a compulsion. Many people asked me how to do this, so that’s why I decided to write about it. Then we're going to step by step replace the ListView with a RecyclerView. As FloatingActionButton extends ImageView, you’ll use android:src or any of the methods such as setImageDrawable() to control the icon shown within the FloatingActionButton. First step towards building list view is to identify the input data, which you want to display in list. RecyclerView를 사용할 때, GridLayoutManager를 사용하여 span을 줄 수 있습니다. Today we are going to learn how to enable single choice/radio button in ListView, GridView and in RecyclerView using RadioButton, you’ll configure the ListView to display a radioButton next to each item. This image approach is a little old school but it may still come in handy once in a while. But what if I tell you that you can implement single item click listener on RecyclerView without any custom classes or interfaces. Why use RecyclerView? RecyclerView is a container for displaying large data sets that can be scrolled very efficiently by maintaining a limited number of views. We can handle this issue by using a RecyclerView RecyclerView is similar to ListView, but it is more smart about heap memory. and can make ListView as you require. RecyclerView can be used to implement ListView, GridView and Staggered GridView. Ever since it was added to the Android support library in late 2014, it has eclipsed the ListView widget as the most preferred widget for displaying large, complex lists. This basically means that the API is not fixed and you should expect changes between releases. It is a container used to display large amount of data sets that can be scrolled very efficiently by maintaining a limited number of views. 53 Responses to ListView with Images and Text using Simple Adapter in Android John on September 3, 2012 at 11:37 pm Hello, this is a very good example, but how could I do it if the images are not resources in the project??. This method takes three parameters: first is gravity of toast on screen and two others set toast offset from the starting position (which is set by the first parameter):. LayoutManager: Positions items within the RecyclerView. You get advantages like better layout managers, easier. Participate in discussions with other Treehouse members and learn. It has be included in the Android SDK since the API 1. You can combine many components like TextView, CheckBox, ImageView, etc. RecyclerView Refresher. Direct horizontal scrolling is not supported in ListView. - CursorRecyclerAdapter. In that case, dx and dy will be 0. How we can organize their layout, information that images must be downloaded out of the UI…. java and do the below changes to achieve the swipe refresh list view. ListView dan RecyclerView are pretty common widget that has been used on Native Android development. The CardView widget, on the other hand, is a new component that does not "upgrade" an existing component. The biggest challenge comes with the user interaction with this list, and making it feel like the standard picture slideshow that we are all used to. xml for grid item of RecyclerView and paste the following code in it. 0 release of Talon for Twitter, was a refresh of the drag-dismiss support, on the the profiles and tweet viewer. The approaches for ListView, GridView and RecyclerView (the successor to ListView) are documented here. The Android RecyclerView solves many of these problems, but requires a bit more care and feeding out of the box. It extends the RecyclerView. Adapter to access our data source and populate each item with content from the data source. As you all know. Ever since it was added to the Android support library in late 2014, it has eclipsed the ListView widget as the most preferred widget for displaying large, complex lists. Click to share on Twitter (Opens in new window) Click to share on Facebook (Opens in new window). Why use RecyclerView? RecyclerView is a container for displaying large data sets that can be scrolled very efficiently by maintaining a limited number of views. The RecyclerView widget is a more advanced and flexible version of ListView. Nevertheless, studying ListView still has it's benefits: You can gain insights into why RecyclerView works the way it does; You may run into ListView in legacy code, and it's best to know how to work with it ; By working through this tutorial, you'll become familiar with ListView, and you'll do so by creating a recipe list app. simple_list_item_multiple_choice) and setting the selection mode as multiple using ListView. Tutorial About GridView and ListView is finished, Now we will make a Grid and List into one using Widged RecyclerView. Android spinner is like the drop down menu with multiple values from which the end user can select only one value. Use RecyclerView widget when you have lists that change dynamically. use recyclerView instead, setHasStableIds to true on its adapter, implement id generation inside your adapter, and, when you want to expand, insert an appropriate data element corresponding to the expanded card view into your adapter's dataset. My recommendation is to use only RecyclerView for lists going forward. How to hide/show Toolbar when list is scrolling (part 2) 28 Feb 2015. Way late! I have only myself to blame. In my next post, I’ll cover more than just display. Basic Setup. Example Of RecyclerView As Vertical GridView In Android Studio: Step 5: Create a new XML file rowlayout. These offer more options and functionality, but are slightly more complex to use. void onDraw (Canvas c, RecyclerView parent, RecyclerView. You can tell from its description that RecyclerView is supposed to replace ListView, and there aren't a lot of Views more important than ListView in the toolbag. It extends the RecyclerView. Android RatingBar displays the rating in stars. This example demonstrate about How to add dividers and spaces between items in RecyclerView. Most of time ListView and RecyclerView are used to show uniform item view, such as a simple text…. LayoutManager: Positions items within the RecyclerView. So in this tutorial we will see how to add items Dynamically in RecyclerView. It is supposed to be the successor of ListView and GridView. The navigation drawer is one of the most. You need to run it on the real device to test the application. @Oddbjornbakke Thanks for the respone! I'm using Xamarin forms porting to Android only. It was included in API level 22 (Lollipop) in the support-v7 library. This guide explains how to use and customize RecyclerView in Xamarin. So What is a RecyclerView? As I quoted from https://developer. WrapLayout This sample demonstrates an orientation-sensitive WrapLayout class that arranges its children horizontally across the page, and then wraps the display of subsequent children to additional rows. RecyclerView. ListView VS RecyclerView. If you'd like to see some sample code for RecyclerView, check out the RecyclerView Sample App. This Android tutorial explains how to create a ListView with fast scroll,customize its style attributes thumb and track drawable,text color,preview background. in this example, you’ll see how you’ll be able to customise the ListView so that you’ll be able to show pictures, multiple lines of text, and more. …I'm going to replace out this ListView…with the RecyclerView…and I'll type in Android. This method returns the ListView widget which will then be added to the body of the Scaffold we created earlier. How to hide/show Toolbar when list is scrolling (part 2) 28 Feb 2015. In future i will be trying to update a new project where i will be. This new component is a big step because the ListView is one of the most used UI widgets. When a user touches an item in the RecyclerView, an item-click event is generated to notify the app as to which item was touched. RecyclerView expects the developer to contribute a RecyclerView. It's 3 AM right now. Ask Question Asked 5 years, 4 months ago. 0 (API Level 11). Adapter - To handle the data collection and bind it to the view; LayoutManager - Helps in positioning the items. recyclerview selected item, recyclerview, recyclerview android, recyclerview select, android listview highlight selected item, android login show in recyclerview, android recyclerview, highlight. You'll learn to build a recyclerview adapter class from scratch and display images and text. LayoutManager: Responsible for positioning individual item views inside the RecyclerView. But day by day the RecyclerView took the whole stage and there was almost nothing left for the old ListView. RecyclerView is a view group for displaying collections; it is designed to be a more flexible replacement for older view groups such as ListView and GridView. While not a direct feature of Material Design, RecyclerView is replacing ListView, as something more versatile and powerful. Did you understand anything? At least I did not. ViewHolder and has one job, which is to cache all views by finding them by their ID. To understand how RecyclerView works in a typical application, this topic explores the RecyclerViewer sample app, a simple code example that uses RecyclerView to display a large collection of photos:. RecyclerView is Compatible with Api level 7 onward . setMaxRecycledViews(SOME_VIEW_TYPE, POOL_CAPACITY); This is a very important point of flexibility. In this article we will see how to make Image Slider with ViewPager on android platform. Adapters Use in ListView: An adapter is a bridge between UI component and data source that helps us to fill data in UI component. For the first two, RecyclerView uses LayoutManager and ItemAnimator. Both ListView and RecyclerView are similar in that they allow developers to display a collection of items in a table, or list, that can be scrolled through. Nowadays, if you need a listing functionality, the RecyclerView is the place to go. Think of Recyclerview not as a ListView 1:1 replacement but rather as a more flexible component for complex use cases. It is in the Android SDK since the API 1. It's similar to a ListView, but with many updated features, including the ability to implement both horizontal and vertical lists. xml for grid item of RecyclerView and paste the following code in it. What I don't get is when to use ListView and when to use RecyclerView. ListView Custom Renderer This sample demonstrates a custom renderer that encapsulates platform-specific list controls and native cell layouts. Let’s talk about RecyclerView! This is a very important design element for Android and almost every application should implement it. Of all the great advantages RecyclerView has over ListView, one feature that I miss a lot is fast scrolling where you could drag a thumb drawable and scroll around the list. - [Instructor] Many times I've noticed…when people first start using the RecyclerView,…they immediately throw away the ListView. My recommendation is to use only RecyclerView for lists going forward. LayoutManager. RecyclerView and CardView. Both ListView and RecyclerView are similar in that they allow developers to display a collection of items in a table, or list, that can be scrolled through. It's 3 AM right now. Basic Setup. Android Horizontal ListView is required in apps where we create product listing. Start the new project. I'm going to replace out this ListView with the RecyclerView and I'll… Practice while you learn with exercise files. RecyclerView is an evolutionary version of Listview — one of the most important widgets used in Android development. When I made this change the RecyclerView would not display, almost like its height was '0'. In this post we will talk about RecyclerView. * If your use of RecyclerView falls into this category, set this to {@code true}. Also, we now know the need of layout managers and how they can be used to change the look of the recycler layout as well as how adapter works internally to recycle, reuse views and bind data as per the. As for now you will instantiate RecyclerView and set the adapter to RecyclerView as following way. Learn how to use pull to refresh aka SwipeRefreshLayout in Android Studio with example using ListView and RecyclerView. This example demonstrates how to integrate Sorted Recycler View by creating a beautiful student records app that displays student name with age. if you do it all correctly, you'll get some automatic recyclerView animations going. 0 release of Talon for Twitter, was a refresh of the drag-dismiss support, on the the profiles and tweet viewer. ListView supports only simple linear list view with vertical scrolling. RecyclerView is Compatible with Api level 7 onward . RecyclerView Adapter – Recycler-View requires a Recycler-View Adapter to populate and manage the items. It took days for implenting the animations and Google made it just too easy to use animations. First delete the usual "Hello World" textView. This article shows how powerful and easy to use these two widgets can be together. It has more flexibility than ListView. android - How to set TextView disabled color Android RecyclerView add remove item example. You actually can use the same adapter. Expandable RecyclerView is one of the most important feature in Android which can be easily created for our application using Big Nerd Ranch’s Expandable RecyclerView Library It contains two views one is parent view and other is child view. Why use RecyclerView? RecyclerView is a container for displaying large data sets that can be scrolled very efficiently by maintaining a limited number of views. As the name suggests, Android RecyclerView is used to reuse cells when scrolling up and down by recycling the items in the list. RecyclerView will attempt to synthesize visible structural change events for adapters that report that they have stable IDs when this method is used. Here is an example of Countdown Timer in Listview android. To add a RecyclerView to a layout is quite similar…to a ListView. The List interface provides a special iterator, called a ListIterator, that allows element insertion and replacement, and bidirectional access in addition to the normal operations that the Iterator interface provides. When data is written, it's written to this local version first.