From 27d4b5eba717d535a8c464e622122b9886c9af8f Mon Sep 17 00:00:00 2001
From: Karl Tauber <karl@jformdesigner.com>
Date: Wed, 15 Jan 2020 11:05:16 +0100
Subject: [PATCH] ToggleButton: Support per component styling for tab-style
 toggle buttons with client properties `JToggleButton.tab.underlineHeight`
 (integer), `JToggleButton.tab.underlineColor` (Color) and
 `JToggleButton.tab.selectedBackground` (Color) (issue #45)

---
 CHANGELOG.md                                  |  4 +++
 .../formdev/flatlaf/FlatClientProperties.java | 34 +++++++++++++++++++
 .../flatlaf/ui/FlatToggleButtonUI.java        | 14 ++++++--
 3 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index c9bef8e1..41dcd972 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,10 @@ FlatLaf Change Log
   changed (is no longer an instance of `FlatButtonBorder`).
 - ToggleButton: Renamed toggle button type "underline" to "tab" (value of client
   property `JButton.buttonType` is now `tab`).
+- ToggleButton: Support per component styling for tab-style toggle buttons with
+  client properties `JToggleButton.tab.underlineHeight` (integer),
+  `JToggleButton.tab.underlineColor` (Color) and
+  `JToggleButton.tab.selectedBackground` (Color). (issue #45)
 - ToggleButton: No longer use focus width for tab-style toggle buttons to
   compute component size, which reduces/fixes component size in "Flat IntelliJ"
   and "Flat Darcula" themes.
diff --git a/flatlaf-core/src/main/java/com/formdev/flatlaf/FlatClientProperties.java b/flatlaf-core/src/main/java/com/formdev/flatlaf/FlatClientProperties.java
index be2707d6..016b048b 100644
--- a/flatlaf-core/src/main/java/com/formdev/flatlaf/FlatClientProperties.java
+++ b/flatlaf-core/src/main/java/com/formdev/flatlaf/FlatClientProperties.java
@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf;
 
+import java.awt.Color;
 import java.util.Objects;
 import javax.swing.JComponent;
 
@@ -124,6 +125,30 @@ public interface FlatClientProperties
 	 */
 	String PLACEHOLDER_TEXT = "JTextField.placeholderText";
 
+	/**
+	 * Height of underline if toggle button type is {@link #BUTTON_TYPE_TAB}.
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JToggleButton}<br>
+	 * <strong>Value type</strong> {@link java.lang.Integer}
+	 */
+	String TAB_BUTTON_UNDERLINE_HEIGHT = "JToggleButton.tab.underlineHeight";
+
+	/**
+	 * Color of underline if toggle button type is {@link #BUTTON_TYPE_TAB}.
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JToggleButton}<br>
+	 * <strong>Value type</strong> {@link java.awt.Color}
+	 */
+	String TAB_BUTTON_UNDERLINE_COLOR = "JToggleButton.tab.underlineColor";
+
+	/**
+	 * Background color if selected and toggle button type is {@link #BUTTON_TYPE_TAB}.
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JToggleButton}<br>
+	 * <strong>Value type</strong> {@link java.awt.Color}
+	 */
+	String TAB_BUTTON_SELECTED_BACKGROUND = "JToggleButton.tab.selectedBackground";
+
 	/**
 	 * Checks whether a client property of a component has the given value.
 	 */
@@ -148,4 +173,13 @@ public interface FlatClientProperties
 		Object value = c.getClientProperty( key );
 		return (value instanceof Integer) ? (int) value : defaultValue;
 	}
+
+	/**
+	 * Checks whether a client property of a component is a color and returns its value.
+	 * If the client property is not set, or not a color, defaultValue is returned.
+	 */
+	static Color clientPropertyColor( JComponent c, String key, Color defaultValue ) {
+		Object value = c.getClientProperty( key );
+		return (value instanceof Color) ? (Color) value : defaultValue;
+	}
 }
diff --git a/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToggleButtonUI.java b/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToggleButtonUI.java
index 2c232de3..c664a7dd 100644
--- a/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToggleButtonUI.java
+++ b/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatToggleButtonUI.java
@@ -144,6 +144,12 @@ public class FlatToggleButtonUI
 
 				b.repaint();
 				break;
+
+			case TAB_BUTTON_UNDERLINE_HEIGHT:
+			case TAB_BUTTON_UNDERLINE_COLOR:
+			case TAB_BUTTON_SELECTED_BACKGROUND:
+				b.repaint();
+				break;
 		}
 	}
 
@@ -160,7 +166,7 @@ public class FlatToggleButtonUI
 
 			// paint background
 			Color background = buttonStateColor( c,
-				selected ? tabSelectedBackground : null,
+				selected ? clientPropertyColor( c, TAB_BUTTON_SELECTED_BACKGROUND, tabSelectedBackground ) : null,
 				null, tabFocusBackground, tabHoverBackground, null );
 			if( background != null ) {
 				g.setColor( background );
@@ -169,8 +175,10 @@ public class FlatToggleButtonUI
 
 			// paint underline if selected
 			if( selected ) {
-				int underlineHeight = UIScale.scale( tabUnderlineHeight );
-				g.setColor( c.isEnabled() ? tabUnderlineColor : tabDisabledUnderlineColor );
+				int underlineHeight = UIScale.scale( clientPropertyInt( c, TAB_BUTTON_UNDERLINE_HEIGHT, tabUnderlineHeight ) );
+				g.setColor( c.isEnabled()
+					? clientPropertyColor( c, TAB_BUTTON_UNDERLINE_COLOR, tabUnderlineColor )
+					: tabDisabledUnderlineColor );
 				g.fillRect( 0, height - underlineHeight, width, underlineHeight );
 			}
 		} else