Unity Color PropertyDrawer 如何使Color编辑更加便捷

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简介

在Inspector检视面板编辑Color值时，如果我们想要使用16进制颜色或修改其Alpha透明值时，需要打开Color窗口进行修改：

本文通过为Color类自定义PropertyDrawer来实现更便捷的颜色值修改，如下图所示，在Color编辑后面增加了16进制颜色和Alpha透明值字段的绘制：

实现

Custom Property Drawer

创建ColorPropertyDrawer类继承PropertyDrawer并为其添加CustomPropertyDrawer特性，重写OnGUI函数：

using UnityEngine;
using UnityEditor;

[CustomPropertyDrawer(typeof(Color))]
public class ColorPropertyDrawer : PropertyDrawer
{
    
    
    public override void OnGUI(Rect position, SerializedProperty property, GUIContent title)
    {
    
    
        base.OnGUI(position, property, title);
    }
}

在OnGUI函数中自定义Color属性的绘制方法。

16进制颜色转Color值

通过EditorGUI中TextField为16进制颜色数据提供编辑输入，并将输入的16进制颜色数据转换为Color值，转换方法如下：

//16进制颜色转Color值
private static Color FromHex(string hexValue, float alpha)
{
    
    
    if (string.IsNullOrEmpty(hexValue)) return Color.clear;
    if (hexValue[0] == '#') hexValue = hexValue.TrimStart('#');
    if (hexValue.Length > 6) hexValue = hexValue.Remove(6, hexValue.Length - 6);
    int value = int.Parse(hexValue, NumberStyles.HexNumber);
    int r = value >> 16 & 255;
    int g = value >> 8 & 255;
    int b = value & 255;
    return new Color(r / 255f, g / 255f, b / 255f, alpha);
}

完整代码：

using UnityEngine;
using UnityEditor;
using System.Globalization;

[CustomPropertyDrawer(typeof(Color))]
public class ColorPropertyDrawer : PropertyDrawer
{
    
    
    private const float spacing = 5f;
    private const float hexWidth = 60f;
    private const float alphaWidth = 32f;

    public override void OnGUI(Rect position, SerializedProperty property, GUIContent title)
    {
    
    
        title = EditorGUI.BeginProperty(position, title, property);
        position = EditorGUI.PrefixLabel(position, GUIUtility.GetControlID(FocusType.Passive), title);

        var indent = EditorGUI.indentLevel;
        EditorGUI.indentLevel = 0;

        float colorWidth = position.width - hexWidth - spacing - alphaWidth - spacing;

        Color newColor = EditorGUI.ColorField(new Rect(position.x, position.y, colorWidth, position.height), property.colorValue);
        if (!newColor.Equals(property.colorValue))
            property.colorValue = newColor;

        string hex = EditorGUI.TextField(new Rect(position.x + colorWidth + spacing, position.y, hexWidth, position.height), ColorUtility.ToHtmlStringRGB(property.colorValue));
        try
        {
    
    
            newColor = FromHex(hex, property.colorValue.a);
            if (!newColor.Equals(property.colorValue))
                property.colorValue = newColor;
        }
        finally {
    
     }

        float newAlpha = EditorGUI.Slider(new Rect(position.x + colorWidth + hexWidth + (spacing * 2f), position.y, alphaWidth, position.height), property.colorValue.a, 0f, 1f);
        if (!newAlpha.Equals(property.colorValue.a))
            property.colorValue = new Color(property.colorValue.r, property.colorValue.g, property.colorValue.b, newAlpha);

        EditorGUI.indentLevel = indent;
        EditorGUI.EndProperty();
    }

    //16进制颜色转Color值
    private static Color FromHex(string hexValue, float alpha)
    {
    
    
        if (string.IsNullOrEmpty(hexValue)) return Color.clear;
        if (hexValue[0] == '#') hexValue = hexValue.TrimStart('#');
        if (hexValue.Length > 6) hexValue = hexValue.Remove(6, hexValue.Length - 6);
        int value = int.Parse(hexValue, NumberStyles.HexNumber);
        int r = value >> 16 & 255;
        int g = value >> 8 & 255;
        int b = value & 255;
        return new Color(r / 255f, g / 255f, b / 255f, alpha);
    }
}