UnityDynamicScrollRect
An optimized approach to lists with dozens of elements.
How to use
you can find a pratical example inside this repository in DynamicScrollScene scene
1 - Create a class to store all the information that each element of the list will need.
public class ExampleData
{
public int postId;
public int id;
public string name;
public string email;
public string body;
}2 - Create a class that extends DynamicScrollObject<ExampleData> and implement its abstract members (make sure to call base.updateScrollObject(item, index);) and set the object width and height in currentWidth and currentHeight.
public class ExampleDynamicObject : DynamicScrollObject<ExampleData>
{
public override float currentHeight { get; set; }
public override float currentWidth { get; set; }
private Text idText;
private Text nameEmailText;
private Text bodyText;
public void Awake()
{
currentHeight = GetComponent<RectTransform>().rect.height;
currentWidth = GetComponent<RectTransform>().rect.width;
idText = transform.Find("PostId").GetComponent<Text>();
nameEmailText = transform.Find("NameEmail").GetComponent<Text>();
bodyText = transform.Find("Body").GetComponent<Text>();
}
public override void updateScrollObject(ExampleData item, int index)
{
base.updateScrollObject(item, index);
idText.text = item.id.ToString();
nameEmailText.text = string.Format("{0} ({1})", item.name, item.email);
bodyText.text = item.body;
}
}3 - Create a class to initiate the DynamicList (use DynamicScrollRect instead of ScrollRect)
public class ExampleScroll : MonoBehaviour
{
public DynamicScrollRect verticalScroll;
public GameObject referenceObject;
private DynamicScroll<ExampleData, ExampleDynamicObject> mVerticalDynamicScroll = new DynamicScroll<ExampleData, ExampleDynamicObject>();
public IEnumerator Start()
{
WWW www = new WWW(@"https://jsonplaceholder.typicode.com/comments");
yield return www;
var data = JsonHelper.getJsonArray<ExampleData>(www.text);
mVerticalDynamicScroll.spacing = 5f;
mVerticalDynamicScroll.Initiate(verticalScroll, data, 0, referenceObject);
}
}DynamicScroll<T, T1> public overview
Properties
| name | type | description |
|---|---|---|
spacing |
float | Value that represent the spacing between elements of the list |
centralizeOnStop |
bool | If the list should centralize the closest element to the center of the viewport after stop moving |
objectPool |
readonly Pooling < T1 > | The elements of the list |
OnDragEvent |
Action < Vector2 > | Event that triggers whenever the user scrolls the list, the parameter represent the velocity of the drag |
OnBeginDragEvent |
UnityEvent < PointerEventData > | Event that triggers in the first frame of dragging |
OnEndDragEvent |
UnityEvent < PointerEventData > | Event that triggers in the last frame of dragging |
Methods
dynamicScroll.Initiate
-
Description: Initiate the scroll rect with
objReferenceobjects applyinginfoListdata. -
Parameters:
| name | type | description |
|---|---|---|
scrollRect |
ScrollRect | a reference to the scroll rect |
infoList |
T[] | the list with the data information |
startIndex |
int | the item of index startindex will be the first element of the list |
objReference |
GameObject | a reference of the object that will be inside the list |
createMoreIfNeeded |
bool | if the list needs more itens, it will create more if createMoreIfNeeded == true |
forceAmount |
int? | if setted, it will force forceAmount objects to be created at start |
dynamicScroll.ChangeList
-
Description: Change the current list of the scroll rect.
-
Parameters :
| name | type | description |
|---|---|---|
infoList |
T[] | the list with the data information |
startIndex |
int | the item of index startindex will be the first element of the list. If -1, the current index will be setted. |
resetContentPosition |
bool | reset list position |
dynamicScroll.RefreshPosition
- Description: Repaint the whole scroll rect. This is useful if any item inside the scroll rect changes the size (
currentWidthandcurrentHeight).
dynamicScroll.ToggleScroll
-
Description: Enable or Disable the ability to scroll the list.
-
Parameters :
| name | type | description |
|---|---|---|
active |
bool | enable or Disable the ability to scroll the list |
dynamicScroll.CanMove
-
Description: Returns true if all directions send thro parameter are available.
-
Parameters :
| name | type | description |
|---|---|---|
directions |
ScrollDirection | Enum flag with all the directions you want to know if are available |
dynamicScroll.MoveToIndex
-
Description: Tweens the content to centralize the object of index specified in the parameters.
-
Parameters :
| name | type | description |
|---|---|---|
i |
int | Index of the element to be centralized |
totalTime |
float? | Total time to the animation happen (if you choose to input this value, the next one will be ignored) |
timePerElement |
float? | This value will be multiplied by the difference between the current centralized element and the target element to get the totalTime |
dynamicScroll.GetCentralizedObject
- Description: Returns the closest element to the center of the viewport.
dynamicScroll.GetLowest
- Description: Returns the most left (if horizontal scroll) or most bottom (if vertical scroll) T1 object.
dynamicScroll.GetHighest
- Description: Returns the most right (if horizontal scroll) or most upper (if vertical scroll) T1 object.