Unity 动态更换Image图片 && UI自适应

一、动态更换Image图片

前提：Image源文件必须存放在自行创建的文件夹[Resources]中

方式一：typeof 类型 Resources.Load()动态更换Image

Image img;
//image路径
string path = "Images/Item/img";
//参数为资源路径和资源类型
Sprite sprite = Resources.Load(path,typeof(Sprite)) as Sprite;
//动态更换image
Img.sprite = sprite;

方式二：泛型
这里的icon_{数值:00}实际上是图片的名称，只不过用的是正则的方式替换了

Sprite sprite = Resources.Load<Sprite>($"Images/icon_{数值:00}");

二、UI自适应

using UnityEngine;
using UnityEngine.UI;

public enum AnchorPresets
{
    TopLeft,
    TopCenter,
    TopRight,

    MiddleLeft,
    MiddleCenter,
    MiddleRight,

    BottomLeft,
    BottonCenter,
    BottomRight,
    BottomStretch,

    VertStretchLeft,
    VertStretchRight,
    VertStretchCenter,

    HorStretchTop,
    HorStretchMiddle,
    HorStretchBottom,

    StretchAll
}
public enum PivotPresets
{
    TopLeft,
    TopCenter,
    TopRight,

    MiddleLeft,
    MiddleCenter,
    MiddleRight,

    BottomLeft,
    BottomCenter,
    BottomRight,
}
public enum UILocation
{
    Left,
    Center,
    Right
}
public static class UIUtil
{
    /// 

    /// 自适应Image,不考虑高度,如果图片比父物体要宽,图片将会自适应
    /// 
    /// 
    /// 是否进行高度自适应,有滑动条可忽略
    /// 缩放倍数
    public static void AdaptiveUIImage( this Image mImage, bool mIsAdaptHeight = false, float mSize = 0.95f)
    {
        if (mImage.type != Image.Type.Simple)
            return;
        mImage.SetNativeSize ();
        if (mImage.rectTransform.sizeDelta.x > mImage.rectTransform.parent.GetComponent<RectTransform> ().sizeDelta.x)
        {
            float w = mImage.rectTransform.parent.GetComponent<RectTransform> ().sizeDelta.x / mImage.rectTransform.sizeDelta.x;
            //Debug.Log ("图片宽:" + f + "%");
            mImage.rectTransform.sizeDelta = new Vector2 (mImage.rectTransform.sizeDelta.x * w, mImage.rectTransform.sizeDelta.y * w) * mSize;
        }
        if (mIsAdaptHeight)
        {
            if (mImage.rectTransform.sizeDelta.y > mImage.rectTransform.parent.GetComponent<RectTransform> ().sizeDelta.y)
            {
                float h = mImage.rectTransform.parent.GetComponent<RectTransform> ().sizeDelta.y / mImage.rectTransform.sizeDelta.y;
                //Debug.Log ("图片宽:" + f + "%");
                mImage.rectTransform.sizeDelta = new Vector2 (mImage.rectTransform.sizeDelta.x * h, mImage.rectTransform.sizeDelta.y * h) * mSize;
            }
        }
    }
    /// 

    /// 自适应Text,不考虑宽度(宽度可自定义),如果txt数量过多导致显示不出来下一行,可自适应高度
    /// 
    /// text
    public static void AdaptiveUIText( this Text mText, bool mIsAdaptWide = false, float mSize = 0.95f )
    {
        if (mIsAdaptWide)
        {
            mText.rectTransform.sizeDelta = new Vector2 (mText.transform.parent.GetComponent<RectTransform>().sizeDelta.x* mSize, mText.rectTransform.sizeDelta.y);
        }
        mText.rectTransform.sizeDelta = new Vector2 (mText.rectTransform.sizeDelta.x, mText.preferredHeight);
    }

    /// 

    /// UI自适应(子物体锚点不允许为Stretch模式)
    /// 
    /// 父物体
    /// 自适应位置
    /// 间隔距离
    /// 父物体是否跟随子物体调整大小
    public static void AdaptiveUI( this RectTransform mUIParent, UILocation mUILocation = UILocation.Center, float mGap = 10f, bool mAlterUIParent = true )
    {
        #region 锚点固定左上角
        foreach (RectTransform item in mUIParent)
        {
            item.SetAnchor (AnchorPresets.TopLeft);
        }
        #endregion

        RectTransform UIItem = null;
        foreach (Transform item in mUIParent.transform)
        {
            if (!item.gameObject.activeSelf)
                continue;

            #region 自适应Text与Image
            Image image = item.GetComponent<Image> ();
            Text text = item.GetComponent<Text> ();
            if (image)
                AdaptiveUIImage (image);
            if (text)
                AdaptiveUIText (text,true);
            #endregion

            if (UIItem == null)
            {
                UIItem = item.GetComponent<RectTransform> ();
                UIItem.anchoredPosition = new Vector2 (UIItem.anchoredPosition.x, ( UIItem.sizeDelta.y / -2 ));
            }
            else
            {
                float itemx = item.GetComponent<RectTransform> ().anchoredPosition.x;
                float itemy = UIItem.anchoredPosition.y - ( item.GetComponent<RectTransform> ().sizeDelta.y / 2 ) - ( UIItem.sizeDelta.y / 2 );
                item.GetComponent<RectTransform> ().anchoredPosition = new Vector2 (itemx, itemy);
                UIItem = item.GetComponent<RectTransform> ();
            }
            SetUILocation (mUIParent, item.GetComponent<RectTransform> (), mUILocation, mGap);
        }
        //设置父物体的长度
        if (mAlterUIParent)
        {
            float mUIParent_Y = ( UIItem.anchoredPosition.y * -1 ) + ( UIItem.sizeDelta.y / 2 );
            mUIParent.sizeDelta = new Vector2 (mUIParent.sizeDelta.x, mUIParent_Y + mGap);
            //mUIParent.SetPivot (PivotPresets.TopCenter);
            //mUIParent.SetAnchor ( AnchorPresets.TopLeft);
        }
    }

    static void SetUILocation( RectTransform mUIParent, RectTransform mTaggetUI, UILocation mUILocation, float mGap )
    {
        float mTaggetUI_X = 0;
        float mTaggetUI_Y = mTaggetUI.anchoredPosition.y - mGap;
        switch (mUILocation)
        {
            case UILocation.Left:
                mTaggetUI_X = mTaggetUI.sizeDelta.x / 2 + mGap;
                break;
            case UILocation.Center:
                mTaggetUI_X = mUIParent.sizeDelta.x / 2;
                break;
            case UILocation.Right:
                mTaggetUI_X = mUIParent.sizeDelta.x - ( mTaggetUI.sizeDelta.x / 2 ) - mGap;
                break;
        }
        mTaggetUI.anchoredPosition = new Vector2 (mTaggetUI_X, mTaggetUI_Y);
    }

    public static void SetAnchor( this RectTransform source, AnchorPresets allign, int offsetX = 0, int offsetY = 0 )
    {
        source.anchoredPosition = new Vector3 (offsetX, offsetY, 0);

        switch (allign)
        {
            case ( AnchorPresets.TopLeft ):
                {
                    source.anchorMin = new Vector2 (0, 1);
                    source.anchorMax = new Vector2 (0, 1);
                    break;
                }
            case ( AnchorPresets.TopCenter ):
                {
                    source.anchorMin = new Vector2 (0.5f, 1);
                    source.anchorMax = new Vector2 (0.5f, 1);
                    break;
                }
            case ( AnchorPresets.TopRight ):
                {
                    source.anchorMin = new Vector2 (1, 1);
                    source.anchorMax = new Vector2 (1, 1);
                    break;
                }

            case ( AnchorPresets.MiddleLeft ):
                {
                    source.anchorMin = new Vector2 (0, 0.5f);
                    source.anchorMax = new Vector2 (0, 0.5f);
                    break;
                }
            case ( AnchorPresets.MiddleCenter ):
                {
                    source.anchorMin = new Vector2 (0.5f, 0.5f);
                    source.anchorMax = new Vector2 (0.5f, 0.5f);
                    break;
                }
            case ( AnchorPresets.MiddleRight ):
                {
                    source.anchorMin = new Vector2 (1, 0.5f);
                    source.anchorMax = new Vector2 (1, 0.5f);
                    break;
                }

            case ( AnchorPresets.BottomLeft ):
                {
                    source.anchorMin = new Vector2 (0, 0);
                    source.anchorMax = new Vector2 (0, 0);
                    break;
                }
            case ( AnchorPresets.BottonCenter ):
                {
                    source.anchorMin = new Vector2 (0.5f, 0);
                    source.anchorMax = new Vector2 (0.5f, 0);
                    break;
                }
            case ( AnchorPresets.BottomRight ):
                {
                    source.anchorMin = new Vector2 (1, 0);
                    source.anchorMax = new Vector2 (1, 0);
                    break;
                }

            case ( AnchorPresets.HorStretchTop ):
                {
                    source.anchorMin = new Vector2 (0, 1);
                    source.anchorMax = new Vector2 (1, 1);
                    break;
                }
            case ( AnchorPresets.HorStretchMiddle ):
                {
                    source.anchorMin = new Vector2 (0, 0.5f);
                    source.anchorMax = new Vector2 (1, 0.5f);
                    break;
                }
            case ( AnchorPresets.HorStretchBottom ):
                {
                    source.anchorMin = new Vector2 (0, 0);
                    source.anchorMax = new Vector2 (1, 0);
                    break;
                }

            case ( AnchorPresets.VertStretchLeft ):
                {
                    source.anchorMin = new Vector2 (0, 0);
                    source.anchorMax = new Vector2 (0, 1);
                    break;
                }
            case ( AnchorPresets.VertStretchCenter ):
                {
                    source.anchorMin = new Vector2 (0.5f, 0);
                    source.anchorMax = new Vector2 (0.5f, 1);
                    break;
                }
            case ( AnchorPresets.VertStretchRight ):
                {
                    source.anchorMin = new Vector2 (1, 0);
                    source.anchorMax = new Vector2 (1, 1);
                    break;
                }

            case ( AnchorPresets.StretchAll ):
                {
                    source.anchorMin = new Vector2 (0, 0);
                    source.anchorMax = new Vector2 (1, 1);
                    break;
                }
        }
    }

    public static void SetPivot( this RectTransform source, PivotPresets preset )
    {

        switch (preset)
        {
            case ( PivotPresets.TopLeft ):
                {
                    source.pivot = new Vector2 (0, 1);
                    break;
                }
            case ( PivotPresets.TopCenter ):
                {
                    source.pivot = new Vector2 (0.5f, 1);
                    break;
                }
            case ( PivotPresets.TopRight ):
                {
                    source.pivot = new Vector2 (1, 1);
                    break;
                }

            case ( PivotPresets.MiddleLeft ):
                {
                    source.pivot = new Vector2 (0, 0.5f);
                    break;
                }
            case ( PivotPresets.MiddleCenter ):
                {
                    source.pivot = new Vector2 (0.5f, 0.5f);
                    break;
                }
            case ( PivotPresets.MiddleRight ):
                {
                    source.pivot = new Vector2 (1, 0.5f);
                    break;
                }

            case ( PivotPresets.BottomLeft ):
                {
                    source.pivot = new Vector2 (0, 0);
                    break;
                }
            case ( PivotPresets.BottomCenter ):
                {
                    source.pivot = new Vector2 (0.5f, 0);
                    break;
                }
            case ( PivotPresets.BottomRight ):
                {
                    source.pivot = new Vector2 (1, 0);
                    break;
                }
        }
    }
}

UI自适应使用方式

public class UIDemo : MonoBehaviour
{
    public RectTransform UIParent;
    public Image UIImage;
    public Text UIText;
    void Start()
    {
        UIParent.AdaptiveUI ();
        UIImage.AdaptiveUIImage ();
        UIText.AdaptiveUIText ();
    }
}