根据 HorizontalLayoutGroup 等，在 Unity3D 中更正 'FlowLayoutGroup'

Question

假设您想要在 Unity UI 中使用普通 齐平左流 。示例：

事实上，为了回答，我已经“艰难地”实现了左对齐流。在Unity自动布局中设置“垂直行组”，在顶层附加FattieFlow，

public class FattieFlow : MonoBehaviour
{
    public GameObject modelRow;
    public GameObject modelItem;
    public void Flow()
    {
        screen = GetComponent<RectTransform>().rect.width;

        // move downwards any which need to be moved downwards
        int row = 0;
        while (row < transform.childCount)  // (dynamic)
        {
            if (transform.GetChild(row).gameObject.activeSelf) FlowRow(row);
            ++row;
        }
        // et cetera....
    }
}

FattieFlow 将完全重新流向左对齐（通过操纵线条，困难的方式）。这是脚本、演示等：.

但这是一个糟糕的解决方案。

理想情况下，从 UI.HorizontalLayoutGroup and UI.VerticalLayoutGroup 应该可以创建

`FlowLayoutGroup`

它向左齐平布置成一个块。（实际上它应该根据需要扩展等等，块......完全按照 HorizontalLayoutGroup 的行为）。

您似乎必须从 HorizontalOrVerticalLayoutGroup 开始，然后从那里开始工作。

如何做到这一点（如果已经存在）？

Answer 1

到目前为止我想到了这个：

FlowLayoutGroup

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

[AddComponentMenu("Layout/Flow Layout Group", 153)]
public class FlowLayoutGroup : LayoutGroup
{
    public enum Corner { 
        UpperLeft = 0, 
        UpperRight = 1, 
        LowerLeft = 2, 
        LowerRight = 3 
    }

    public enum Constraint { 
        Flexible = 0, 
        FixedColumnCount = 1, 
        FixedRowCount = 2 
    }

    protected Vector2 m_CellSize = new Vector2(100, 100);
    public Vector2 cellSize { 
        get { return m_CellSize; } 
        set { SetProperty(ref m_CellSize, value); } 
    }

    [SerializeField] protected Vector2 m_Spacing = Vector2.zero;
    public Vector2 spacing { 
        get { return m_Spacing; } 
        set { SetProperty(ref m_Spacing, value); } 
    }

    protected FlowLayoutGroup()
    {}

#if UNITY_EDITOR
    protected override void OnValidate()
    {
        base.OnValidate();
    }

#endif

    public override void CalculateLayoutInputHorizontal()
    {
        base.CalculateLayoutInputHorizontal();

        int minColumns = 0;
        int preferredColumns = 0;

        minColumns = 1;
        preferredColumns = Mathf.CeilToInt(Mathf.Sqrt(rectChildren.Count));

        SetLayoutInputForAxis(
            padding.horizontal + (cellSize.x + spacing.x) * minColumns - spacing.x,
            padding.horizontal + (cellSize.x + spacing.x) * preferredColumns - spacing.x,
            -1, 0);
    }

    public override void CalculateLayoutInputVertical()
    {
        int minRows = 0;

        float width = rectTransform.rect.size.x;
        int cellCountX = Mathf.Max(1, Mathf.FloorToInt((width - padding.horizontal + spacing.x + 0.001f) / (cellSize.x + spacing.x)));
//      minRows = Mathf.CeilToInt(rectChildren.Count / (float)cellCountX);
        minRows = 1;
        float minSpace = padding.vertical + (cellSize.y + spacing.y) * minRows - spacing.y;
        SetLayoutInputForAxis(minSpace, minSpace, -1, 1);
    }

    public override void SetLayoutHorizontal()
    {
        SetCellsAlongAxis(0);
    }

    public override void SetLayoutVertical()
    {
        SetCellsAlongAxis(1);
    }

    int cellsPerMainAxis, actualCellCountX, actualCellCountY;
    int positionX;
    int positionY;
    float totalWidth = 0; 
    float totalHeight = 0;

    float lastMaxHeight = 0;

    private void SetCellsAlongAxis(int axis)
    {
        // Normally a Layout Controller should only set horizontal values when invoked for the horizontal axis
        // and only vertical values when invoked for the vertical axis.
        // However, in this case we set both the horizontal and vertical position when invoked for the vertical axis.
        // Since we only set the horizontal position and not the size, it shouldn't affect children's layout,
        // and thus shouldn't break the rule that all horizontal layout must be calculated before all vertical layout.

        float width = rectTransform.rect.size.x;
        float height = rectTransform.rect.size.y;

        int cellCountX = 1;
        int cellCountY = 1;

        if (cellSize.x + spacing.x <= 0)
            cellCountX = int.MaxValue;
        else
            cellCountX = Mathf.Max(1, Mathf.FloorToInt((width - padding.horizontal + spacing.x + 0.001f) / (cellSize.x + spacing.x)));

        if (cellSize.y + spacing.y <= 0)
            cellCountY = int.MaxValue;
        else
            cellCountY = Mathf.Max(1, Mathf.FloorToInt((height - padding.vertical + spacing.y + 0.001f) / (cellSize.y + spacing.y)));

        cellsPerMainAxis = cellCountX;
        actualCellCountX = Mathf.Clamp(cellCountX, 1, rectChildren.Count);
        actualCellCountY = Mathf.Clamp(cellCountY, 1, Mathf.CeilToInt(rectChildren.Count / (float)cellsPerMainAxis));

        Vector2 requiredSpace = new Vector2(
            actualCellCountX * cellSize.x + (actualCellCountX - 1) * spacing.x,
            actualCellCountY * cellSize.y + (actualCellCountY - 1) * spacing.y
        );
        Vector2 startOffset = new Vector2(
            GetStartOffset(0, requiredSpace.x),
            GetStartOffset(1, requiredSpace.y)
        );

        totalWidth = 0;
        totalHeight = 0;
        Vector2 currentSpacing = Vector2.zero;
        for (int i = 0; i < rectChildren.Count; i++)
        {
            SetChildAlongAxis(rectChildren[i], 0, startOffset.x + totalWidth /*+ currentSpacing[0]*/, rectChildren[i].rect.size.x);
            SetChildAlongAxis(rectChildren[i], 1, startOffset.y + totalHeight  /*+ currentSpacing[1]*/, rectChildren[i].rect.size.y);

            currentSpacing = spacing;

            totalWidth += rectChildren[i].rect.width + currentSpacing[0];

            if (rectChildren[i].rect.height > lastMaxHeight)
            {
                lastMaxHeight = rectChildren[i].rect.height;
            }

            if (i<rectChildren.Count-1)
            {
                if (totalWidth + rectChildren[i+1].rect.width + currentSpacing[0] > width )
                {
                    totalWidth = 0;
                    totalHeight += lastMaxHeight + currentSpacing[1];
                    lastMaxHeight = 0;
                }
            }
        }
    }
}

使用方法

将此脚本附加到您的面板，就像您使用其他布局组（如 GridViewLayout）一样
添加 UI 元素（按钮、图像等）作为面板的 child。
将 ContentSizeFitter 组件添加到 children 并将 Horizontal Fit 和 Vertical Fit 属性设置为 Preferred Size
将 Layout Element 组件添加到 child 并设置 Preferred Width 和 Preferred Height 值。这些值将控制 UI 元素的大小。您也可以改用 Min Width 和 Min Height。
根据需要添加任意数量的元素并应用相同的过程以获得所需的大小。

这是检查器中的样子 window :

使用不同尺寸的按钮进行测试，效果很好。

注意：

我从 Unity UI 代码修改了 GridLayoutGroup class 以获得所需的代码行为。因为它是从 LayoutGroup 派生的，它控制 child仁的RectTransform属性。我们需要使用 ContentSizeFitter 和 LayoutElement 在 children 上改变他们的尺寸。
它只适用于从左上角开始的水平流，不像 GridLayout 允许垂直开始，也可以从其他角开始。我不认为这是一个限制，因为这只是 Flow Layout Group.
我还添加了一个 Repository on GithHub 以防有人想为此做出贡献。

谢谢！

Answer 2

还有community-made FlowLayoutGroup包含在“UnityUIExtensions”编译中。它在更新过程中经历了一些修改和用户贡献。

https://bitbucket.org/UnityUIExtensions/unity-ui-extensions/wiki/Controls/FlowLayoutGroup

安装

Recommended to use UPM for Unity 2019+

旁注：项目本身是免费的，如其main page所述。

contribution is optional. The assets / code will always remain FREE

根据 HorizontalLayoutGroup 等，在 Unity3D 中更正 'FlowLayoutGroup'

Correct 'FlowLayoutGroup' in Unity3D, as per HorizontalLayoutGroup etc

unity3d

unity3d-ui

`FlowLayoutGroup`

安装

根据 Horizo​​ntalLayoutGroup 等，在 Unity3D 中更正 'FlowLayoutGroup'

Correct 'FlowLayoutGroup' in Unity3D, as per HorizontalLayoutGroup etc

unity3d

unity3d-ui

FlowLayoutGroup

安装

根据 HorizontalLayoutGroup 等，在 Unity3D 中更正 'FlowLayoutGroup'

`FlowLayoutGroup`