简介
UGUI
图片拖拽排序
demo.gif
DropZone.cs
拖拽Continer
public class DropZone : MonoBehaviour, IDropHandler, IPointerEnterHandler, IPointerExitHandler {
public void OnPointerEnter(PointerEventData eventData) {
if (eventData.pointerDrag == null)
return;
Draggable d = eventData.pointerDrag.GetComponent<Draggable>();
if (d != null)
{
d.placeHolderParent = this.transform;
}
}
public void OnPointerExit(PointerEventData eventData) {
if (eventData.pointerDrag == null)
return;
Draggable d = eventData.pointerDrag.GetComponent<Draggable>();
if (d != null && d.placeHolderParent == this.transform)
{
d.placeHolderParent = d.parentToReturnTo;
}
}
public void OnDrop(PointerEventData eventData) {
Debug.Log(eventData.pointerDrag.name + " dropped on " + gameObject.name);
Draggable d = eventData.pointerDrag.GetComponent<Draggable>();
if (d != null) {
d.parentToReturnTo = this.transform;
}
}
}
PointerEventData.pointerDrag：触发OnPointerEnter的物体OnPointerEnter：Called when a pointer enters the objectOnPointerExit：Called when a pointer exits the objectOnDrop：Called on the object where a drag finishes（有拖拽结束时调用）
Draggable.cs
拖拽Item拖拽出去 原位置创建空物体占位置排序
public class Draggable : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler {
[HideInInspector]
public Transform parentToReturnTo = null;
[HideInInspector]
public Transform placeHolderParent = null;
private GameObject placeHolder = null;
public void OnBeginDrag(PointerEventData eventData) {
placeHolder = new GameObject();
placeHolder.transform.SetParent( this.transform.parent );
LayoutElement le = placeHolder.AddComponent<LayoutElement>();
le.preferredWidth = this.GetComponent<LayoutElement>().preferredWidth;
le.preferredHeight = this.GetComponent<LayoutElement>().preferredHeight;
le.flexibleWidth = 0;
le.flexibleHeight = 0;
placeHolder.transform.SetSiblingIndex(this.transform.GetSiblingIndex() );
parentToReturnTo = this.transform.parent;
placeHolderParent = parentToReturnTo;
this.transform.SetParent(this.transform.parent.parent);
this.GetComponent<CanvasGroup>().blocksRaycasts = false;
}
public void OnDrag(PointerEventData eventData) {
this.transform.position = eventData.position;
if (placeHolder.transform.parent != placeHolderParent)
{
placeHolder.transform.SetParent(placeHolderParent);
}
int newSiblingIndex = placeHolderParent.childCount;
for (int i = 0; i < placeHolderParent.childCount; i++)
{
if (this.transform.position.x < placeHolderParent.GetChild(i).position.x)
{
newSiblingIndex = i;
if (placeHolder.transform.GetSiblingIndex() < newSiblingIndex)
newSiblingIndex--;
break;
}
}
placeHolder.transform.SetSiblingIndex(newSiblingIndex);
}
public void OnEndDrag(PointerEventData eventData) {
this.transform.SetParent(parentToReturnTo);
this.transform.SetSiblingIndex(placeHolder.transform.GetSiblingIndex());
this.GetComponent<CanvasGroup>().blocksRaycasts = true;
Destroy(placeHolder);
}
}
OnEndDrag会在OnDrop之后执行，保证松开时父物体改变
改善：
目前上下两横排，增加横竖排都可以穿插排序目前两排，支持三排多排排序
public void OnDrag(PointerEventData eventData) {
this.transform.position = eventData.position;
if (placeHolder.transform.parent != placeHolderParent)
{
placeHolder.transform.SetParent(placeHolderParent);
isVerticalLayout = (!placeHolder.transform.parent.GetComponent<HorizontalLayoutGroup>());
}
int newSiblingIndex = placeHolderParent.childCount;
if (isVerticalLayout)
{
for (int i = 0; i < placeHolderParent.childCount; i++)
{
if (this.transform.position.y > placeHolderParent.GetChild(i).position.y)
{
newSiblingIndex = i;
if (placeHolder.transform.GetSiblingIndex() < newSiblingIndex)
newSiblingIndex--;
break;
}
}
}
else
{
for (int i = 0; i < placeHolderParent.childCount; i++)
{
if (this.transform.position.x < placeHolderParent.GetChild(i).position.x)
{
newSiblingIndex = i;
if (placeHolder.transform.GetSiblingIndex() < newSiblingIndex)
newSiblingIndex--;
break;
}
}
}
placeHolder.transform.SetSiblingIndex(newSiblingIndex);
}
参考
https://lab.uwa4d.com/lab/5b6630ebd7f10a201ffa5aef
