Unity Editor Font Size Changer -- EditorStyles

README.md

Unity Editor font size editor for the editor styles and skins

Preview	Added custom styles ( 600+ )	Added Global Zoom ( increment all styles in the same time )

GIF PREVIEW : https://imgur.com/8jsy8sN

EditorFontSize.cs

#if UNITY_EDITOR

using System.Collections.Generic;
using UnityEngine;
using UnityEditor;
using System.Reflection;

public class EditorFontSize : EditorWindow
{
    [MenuItem("Window/Editor Font Size")]
    static void Open() => GetWindow<EditorFontSize>("Editor Font Size").minSize = new Vector2(180, 30);

    Dictionary<string, bool> foldouts;

    bool Header( string s )
    {
        if( foldouts == null ) foldouts = new Dictionary<string, bool>();
        if( ! foldouts.ContainsKey( s ) ) foldouts.Add( s, true );
        GUILayout.Space(5);
        var foldout = EditorGUILayout.Foldout( ! foldouts[ s ], s, true );
        foldouts[ s ] = ! foldout;
        return foldout;
    }

    private void OnDisable()
    {
        guiSkins = null;
        editorStyles = null;
        propFontSizevalidity?.Clear();
        propFontSizevalidity = null;
    }

    static List<GUIStyle> styles;

    PropertyInfo[] editorStyles;
    PropertyInfo[] guiSkins;

    void GrapProperties()
    {
        if (editorStyles == null || editorStyles.Length < 1)
        {
            var flags = BindingFlags.Static | BindingFlags.Public | BindingFlags.GetProperty;
            editorStyles = typeof(EditorStyles).GetProperties(flags);
        }
        if (guiSkins == null || guiSkins.Length < 1)
        {
            guiSkins = GUI.skin.GetType().GetProperties();
        }
    }

    Vector2 scroll;

    private void OnGUI()
    {
        rowCount = -1;

        GrapProperties();
        InitStyles();

        var delta = FontSizeRow("Global Zoom", EditorStyles.miniLabel.fontSize.ToString() );
        if (delta != 0 && EditorStyles.miniLabel.fontSize + delta > 0 )
        {
            // Keep watch for duplicates ( Prevent double modifications )
            styles = new List<GUIStyle>();

            foreach (var x in editorStyles)
            {
                if (!ValidFontProp(x, null)) continue;
                var s = (GUIStyle)x.GetValue(null, null);
                if (styles.Contains(s)) continue;
                styles.Add(s);
                s.fontSize += delta;
            }

            foreach (var x in guiSkins)
            {
                if (!ValidFontProp(x, GUI.skin)) continue;
                var s = (GUIStyle)x.GetValue(GUI.skin, null);
                if (styles.Contains(s)) continue;
                styles.Add(s);
                s.fontSize += delta;
            }
            foreach (var x in GUI.skin.customStyles)
            {
                if (!ValidFontStyle(x) || styles.Contains(x)) continue;
                FixZeroSize(x);
                styles.Add(x);
                x.fontSize += delta;
            }

            styles.Clear();
            
            RepaintAll();
        }

        GUILayout.Label("", GUI.skin.horizontalSlider);

        using( var scope = new GUILayout.ScrollViewScope(scroll) )
        {
            scroll = scope.scrollPosition;

            if( Header("Editor Styles" ) )
                foreach (var x in editorStyles ) 
                    ModifyProp( x, null );
            
            if( Header("GUI skins") )
                foreach (var x in guiSkins )
                    ModifyProp(x, GUI.skin );

            if( Header("Custom Styles") )
                foreach( var x in GUI.skin.customStyles )
                {
                    FontSizeRow( x );
                    RepaintAll();
                }
        }
    }
    void RepaintAll() { foreach ( var w in Resources.FindObjectsOfTypeAll<EditorWindow>() ) w.Repaint(); }

    Dictionary<PropertyInfo, bool> propFontSizevalidity;

    bool ValidFontProp( PropertyInfo x , object item)
    {
        if (propFontSizevalidity == null) propFontSizevalidity = new Dictionary<PropertyInfo, bool>();
        if (propFontSizevalidity.ContainsKey(x)) return propFontSizevalidity[x];

        propFontSizevalidity.Add(x, true);

        if (string.IsNullOrEmpty(x.Name)) propFontSizevalidity[x] = false;
        else if (x.PropertyType != typeof(GUIStyle)) propFontSizevalidity[x] = false;
        else if (x.GetValue(item, null) == null) propFontSizevalidity[x] = false;
        else if (((GUIStyle)x.GetValue(item, null)).fontSize < 1 ) propFontSizevalidity[x] = false;
        
        return propFontSizevalidity[x];
    }

    void ModifyProp( PropertyInfo x, object item )
    {
        if (!ValidFontProp(x, item)) return;

        var style = ((GUIStyle)x.GetValue(item, null));
        var val = style.fontSize;
        int ret = FontSizeRow( x.Name, val.ToString() );
        if (ret == 0 || val + ret <= 0) return;
        style.fontSize = val + ret;
        RepaintAll();
    }

    GUIStyle evenBG;
    GUIStyle oddBG;

    void InitStyles()
    {
        if (evenBG != null) return;
        GUIStyle s = "CN EntryBackEven";
        evenBG = new GUIStyle(s);
        s = "CN EntryBackodd";
        oddBG = new GUIStyle(s);
        evenBG.contentOffset = oddBG.contentOffset = new Vector2();
        evenBG.clipping = oddBG.clipping = TextClipping.Clip;
        evenBG.margin = oddBG.margin =
        evenBG.padding = oddBG.padding = new RectOffset();
    }

    int rowCount = 0;

    void FixZeroSize(GUIStyle s) => s.fontSize = s.fontSize < 1 ? 11 : s.fontSize; 

    bool ValidFontStyle( GUIStyle s ) => ! ( s == null || string.IsNullOrEmpty(s.name) );

    void FontSizeRow( GUIStyle s )
    {
        if ( ! ValidFontStyle(s) ) return;

        FixZeroSize( s );

        var x = FontSizeRow(s.name, s.fontSize.ToString());

        if (x != 0 && x + s.fontSize > 0) s.fontSize += x;
    }

    int FontSizeRow( string name, string size )
    {
        if (string.IsNullOrEmpty(name) || size == "0") return 0;

        rowCount ++ ;

        var width = GUILayout.MaxWidth(Screen.width);

        using ( new GUILayout.HorizontalScope( rowCount % 2 == 0 ? evenBG : oddBG, width ) )
        {
            GUILayout.Label(name);
            GUILayout.FlexibleSpace();

            if (GUILayout.Button("-", EditorStyles.miniButtonLeft)) return -1;

            using (new EditorGUI.DisabledGroupScope(true))
                GUILayout.Label(size, EditorStyles.miniButtonMid, GUILayout.Width(30));

            if (GUILayout.Button("+", EditorStyles.miniButtonRight)) return +1;

        }

        return 0;
    }
}

#endif

👍 it works fine in 2022.1.13 version
this is better than nukadelic's code
but everything is reset after enter and exit play mod
can save and reuse font sizes? after exit play mod and reopen unity engine?