Improve GUI of NuGet for Unity window

src/NuGetForUnity/Editor/Ui/RectHelper.cs

@@ -0,0 +1,99 @@
+using UnityEngine;
+
+namespace NugetForUnity
+{
+    /// <summary>
+    ///     Extension methods for manipulating Rect objects.
+    /// </summary>
+    internal static class RectHelper
+    {
+        /// <summary>
+        ///     Expands the boundaries of the Rect by a specified value in all directions.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to add.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect Expand(this Rect rect, float value)
+        {
+            rect.xMin -= value;
+            rect.xMax += value;
+            rect.yMin -= value;
+            rect.yMax += value;
+            return rect;
+        }
+
+        /// <summary>
+        ///     Expands the Rect horizontally by a specified value.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to add.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect ExpandX(this Rect rect, float value)
+        {
+            rect.xMin -= value;
+            rect.xMax += value;
+            return rect;
+        }
+
+        /// <summary>
+        ///     Expands the Rect vertically by a specified value.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to add.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect ExpandY(this Rect rect, float value)
+        {
+            rect.yMin -= value;
+            rect.yMax += value;
+            return rect;
+        }
+
+        /// <summary>
+        ///     Adds a specified value to the X-coordinate of the Rect.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to add.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect AddX(this Rect rect, float value)
+        {
+            rect.x += value;
+            return rect;
+        }
+
+        /// <summary>
+        ///     Adds a specified value to the Y-coordinate of the Rect.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to add.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect AddY(this Rect rect, float value)
+        {
+            rect.y += value;
+            return rect;
+        }
+
+        /// <summary>
+        ///     Sets the width of the Rect to a specified value.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to set.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect SetWidth(this Rect rect, float value)
+        {
+            rect.width = value;
+            return rect;
+        }
+
+        /// <summary>
+        ///     Sets the height of the Rect to a specified value.
+        /// </summary>
+        /// <param name="rect">The rect to update.</param>
+        /// <param name="value">The value to set.</param>
+        /// <returns>The updated Rect.</returns>
+        public static Rect SetHeight(this Rect rect, float value)
+        {
+            rect.height = value;
+            return rect;
+        }
+    }
+}

src/NuGetForUnity/Editor/Ui/Styles.cs

@@ -0,0 +1,186 @@
+using UnityEditor;
+using UnityEngine;
+
+namespace NugetForUnity.Ui
+{
+    /// <summary>
+    ///     Collection of GUIStyle.
+    /// </summary>
+    internal static class Styles
+    {
+        private static GUIStyle cachedSearchFieldStyle;
+
+        private static GUIStyle cachedHeaderStyle;
+
+        private static GUIStyle cachedBackgroundStyle;
+
+        private static GUIStyle cachedLinkLabelStyle;
+
+        /// <summary>
+        ///     Gets the color used for lines used as seperators.
+        /// </summary>
+        public static Color LineColor
+        {
+            get
+            {
+                if (EditorGUIUtility.isProSkin)
+                {
+                    return new Color(0.05f, 0.05f, 0.05f);
+                }
+
+                return new Color(0.6f, 0.6f, 0.6f);
+            }
+        }
+
+        /// <summary>
+        ///     Gets the color used for package authors.
+        /// </summary>
+        public static Color AuthorsTextColor
+        {
+            get
+            {
+                if (EditorGUIUtility.isProSkin)
+                {
+                    return new Color(0.55f, 0.55f, 0.55f);
+                }
+
+                return new Color(0.45f, 0.45f, 0.45f);
+            }
+        }
+
+        /// <summary>
+        ///     Gets the color used for the foldout header.
+        /// </summary>
+        public static Color FoldoutHeaderColor
+        {
+            get
+            {
+                if (EditorGUIUtility.isProSkin)
+                {
+                    return new Color(0.2f, 0.2f, 0.2f);
+                }
+
+                return new Color(0.85f, 0.85f, 0.85f);
+            }
+        }
+
+        /// <summary>
+        ///     Gets a GUI style with a background color the same as the editor's current background color.
+        /// </summary>
+        public static GUIStyle BackgroundStyle
+        {
+            get
+            {
+                if (cachedBackgroundStyle != null)
+                {
+                    return cachedBackgroundStyle;
+                }
+
+                cachedBackgroundStyle = new GUIStyle();
+                var backgroundColor = EditorGUIUtility.isProSkin ? new Color32(56, 56, 56, 255) : new Color32(194, 194, 194, 255);
+                cachedBackgroundStyle.normal.background = CreateSingleColorTexture(backgroundColor);
+
+                return cachedBackgroundStyle;
+            }
+        }
+
+        /// <summary>
+        ///     Gets the GUI style used for the header of the NuGet window.
+        /// </summary>
+        public static GUIStyle HeaderStyle
+        {
+            get
+            {
+                if (cachedHeaderStyle != null)
+                {
+                    return cachedHeaderStyle;
+                }
+
+                cachedHeaderStyle = new GUIStyle();
+                var backgroundColor = EditorGUIUtility.isProSkin ? new Color(0.1f, 0.1f, 0.1f) : new Color(0.4f, 0.4f, 0.4f);
+                cachedHeaderStyle.alignment = TextAnchor.MiddleLeft;
+                cachedHeaderStyle.normal.background = CreateSingleColorTexture(backgroundColor);
+                cachedHeaderStyle.normal.textColor = Color.white;
+
+                return cachedHeaderStyle;
+            }
+        }
+
+        /// <summary>
+        ///     Gets the GUI style used for the package seach field.
+        /// </summary>
+        public static GUIStyle SearchFieldStyle
+        {
+            get
+            {
+                if (cachedSearchFieldStyle != null)
+                {
+                    return cachedSearchFieldStyle;
+                }
+
+                var original = GetStyle("ToolbarSearchTextField");
+                cachedSearchFieldStyle = new GUIStyle(original) { fontSize = 12, fixedHeight = 20f };
+
+                return cachedSearchFieldStyle;
+            }
+        }
+
+        /// <summary>
+        ///     Gets the GUI style used for labels representing a URL / clickable LINK.
+        /// </summary>
+        public static GUIStyle LinkLabelStyle
+        {
+            get
+            {
+                if (cachedLinkLabelStyle != null)
+                {
+                    return cachedLinkLabelStyle;
+                }
+
+                cachedLinkLabelStyle = GetStyle("LinkLabel");
+                return cachedLinkLabelStyle;
+            }
+        }
+
+        /// <summary>
+        ///     From here: http://forum.unity3d.com/threads/changing-the-background-color-for-beginhorizontal.66015/.
+        /// </summary>
+        /// <param name="color">The color to fill the texture with.</param>
+        /// <returns>The generated texture.</returns>
+        private static Texture2D CreateSingleColorTexture(Color color)
+        {
+            const int width = 16;
+            const int height = 16;
+            var pix = new Color32[width * height];
+            Color32 color32 = color;
+            for (var index = 0; index < pix.Length; index++)
+            {
+                pix[index] = color32;
+            }
+
+            var result = new Texture2D(width, height);
+            result.SetPixels32(pix);
+            result.Apply();
+
+            return result;
+        }
+
+        private static GUIStyle GetStyle(string styleName)
+        {
+            var style = GUI.skin.FindStyle(styleName);
+
+            if (style == null)
+            {
+                style = EditorGUIUtility.GetBuiltinSkin(EditorSkin.Inspector).FindStyle(styleName);
+            }
+
+            if (style == null)
+            {
+                Debug.LogError("Missing built-in guistyle " + styleName);
+                style = new GUIStyle();
+            }
+
+            return style;
+        }
+    }
+}