ScrollBar: made styling more flexible by supporting insets and arc for track and thumb (issue #103)

CHANGELOG.md

@@ -3,6 +3,8 @@ FlatLaf Change Log
 
 ## Unreleased
 
+- ScrollBar: Made styling more flexible by supporting insets and arc for track
+  and thumb. (issue #103)
 - Ubuntu Linux: Fixed poorly rendered font. (issue #105)
 
 

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatScrollBarUI.java

@@ -19,6 +19,8 @@ package com.formdev.flatlaf.ui;
 import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Insets;
 import java.awt.Rectangle;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
@@ -52,8 +54,13 @@ import com.formdev.flatlaf.util.UIScale;
  *
  * <!-- FlatScrollBarUI -->
  *
+ * @uiDefault ScrollBar.trackInsets					Insets
+ * @uiDefault ScrollBar.thumbInsets					Insets
+ * @uiDefault ScrollBar.trackArc					int
+ * @uiDefault ScrollBar.thumbArc					int
  * @uiDefault ScrollBar.hoverTrackColor				Color
  * @uiDefault ScrollBar.hoverThumbColor				Color
+ * @uiDefault ScrollBar.hoverThumbWithTrack			boolean
  * @uiDefault Component.arrowType					String	triangle (default) or chevron
  * @uiDefault ScrollBar.showButtons					boolean
  * @uiDefault ScrollBar.buttonArrowColor			Color
@@ -64,8 +71,13 @@ import com.formdev.flatlaf.util.UIScale;
 public class FlatScrollBarUI
 	extends BasicScrollBarUI
 {
+	protected Insets trackInsets;
+	protected Insets thumbInsets;
+	protected int trackArc;
+	protected int thumbArc;
 	protected Color hoverTrackColor;
 	protected Color hoverThumbColor;
+	protected boolean hoverThumbWithTrack;
 
 	protected boolean showButtons;
 	protected String arrowType;
@@ -102,8 +114,13 @@ public class FlatScrollBarUI
 	protected void installDefaults() {
 		super.installDefaults();
 
+		trackInsets = UIManager.getInsets( "ScrollBar.trackInsets" );
+		thumbInsets = UIManager.getInsets( "ScrollBar.thumbInsets" );
+		trackArc = UIManager.getInt( "ScrollBar.trackArc" );
+		thumbArc = UIManager.getInt( "ScrollBar.thumbArc" );
 		hoverTrackColor = UIManager.getColor( "ScrollBar.hoverTrackColor" );
 		hoverThumbColor = UIManager.getColor( "ScrollBar.hoverThumbColor" );
+		hoverThumbWithTrack = UIManager.getBoolean( "ScrollBar.hoverThumbWithTrack" );
 
 		showButtons = UIManager.getBoolean( "ScrollBar.showButtons" );
 		arrowType = UIManager.getString( "Component.arrowType" );
@@ -115,6 +132,8 @@ public class FlatScrollBarUI
 	protected void uninstallDefaults() {
 		super.uninstallDefaults();
 
+		trackInsets = null;
+		thumbInsets = null;
 		hoverTrackColor = null;
 		hoverThumbColor = null;
 
@@ -204,19 +223,15 @@ public class FlatScrollBarUI
 	}
 
 	@Override
-	protected void paintDecreaseHighlight( Graphics g ) {
+	public void paint( Graphics g, JComponent c ) {
-		// do not paint
+		FlatUIUtils.setRenderingHints( (Graphics2D) g );
-	}
+		super.paint( g, c );
-
-	@Override
-	protected void paintIncreaseHighlight( Graphics g ) {
-		// do not paint
 	}
 
 	@Override
 	protected void paintTrack( Graphics g, JComponent c, Rectangle trackBounds ) {
 		g.setColor( hoverTrack ? hoverTrackColor : trackColor );
-		g.fillRect( trackBounds.x, trackBounds.y, trackBounds.width, trackBounds.height );
+		paintTrackOrThumb( g, c, trackBounds, trackInsets, trackArc );
 	}
 
 	@Override
@@ -225,7 +240,30 @@ public class FlatScrollBarUI
 			return;
 
 		g.setColor( hoverThumb ? hoverThumbColor : thumbColor );
-		g.fillRect( thumbBounds.x, thumbBounds.y, thumbBounds.width, thumbBounds.height );
+		paintTrackOrThumb( g, c, thumbBounds, thumbInsets, thumbArc );
+	}
+
+	protected void paintTrackOrThumb( Graphics g, JComponent c, Rectangle bounds, Insets insets, int arc ) {
+		bounds = FlatUIUtils.subtractInsets( bounds, UIScale.scale( insets ) );
+
+		if( arc <= 0 ) {
+			// paint rectangle
+			g.fillRect( bounds.x, bounds.y, bounds.width, bounds.height );
+		} else {
+			// paint round rectangle
+			arc = Math.min( UIScale.scale( arc ), Math.min( bounds.width, bounds.height ) );
+			g.fillRoundRect( bounds.x, bounds.y, bounds.width, bounds.height, arc, arc );
+		}
+	}
+
+	@Override
+	protected void paintDecreaseHighlight( Graphics g ) {
+		// do not paint
+	}
+
+	@Override
+	protected void paintIncreaseHighlight( Graphics g ) {
+		// do not paint
 	}
 
 	@Override
@@ -276,7 +314,7 @@ public class FlatScrollBarUI
 			boolean inThumb = getThumbBounds().contains( x, y );
 			if( inTrack != hoverTrack || inThumb != hoverThumb ) {
 				hoverTrack = inTrack;
-				hoverThumb = inThumb;
+				hoverThumb = inThumb || (hoverThumbWithTrack && inTrack);
 				repaint();
 			}
 		}

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties

@@ -424,6 +424,11 @@ RadioButtonMenuItem.background=@menuBackground
 #---- ScrollBar ----
 
 ScrollBar.width=10
+ScrollBar.trackInsets=0,0,0,0
+ScrollBar.thumbInsets=0,0,0,0
+ScrollBar.trackArc=0
+ScrollBar.thumbArc=0
+ScrollBar.hoverThumbWithTrack=false
 ScrollBar.showButtons=false
 ScrollBar.squareButtons=false
 ScrollBar.buttonArrowColor=$ComboBox.buttonArrowColor

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/uidefaults/FlatDarkLaf_1.8.0_202.txt

@@ -761,17 +761,22 @@ ScrollBar.buttonArrowColor     #9a9da1    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.buttonDisabledArrowColor #585858    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.foreground           #bbbbbb    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.hoverThumbColor      #717678    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.hoverThumbWithTrack  false
 ScrollBar.hoverTrackColor      #494c4f    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.maximumThumbSize     4096,4096    javax.swing.plaf.DimensionUIResource [UI]
 ScrollBar.minimumThumbSize     8,8    javax.swing.plaf.DimensionUIResource [UI]
 ScrollBar.showButtons          false
 ScrollBar.squareButtons        false
 ScrollBar.thumb                #585c5e    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.thumbArc             0
 ScrollBar.thumbDarkShadow      #7e7e7e    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.thumbHighlight       #242424    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.thumbInsets          0,0,0,0    javax.swing.plaf.InsetsUIResource [UI]
 ScrollBar.thumbShadow          #646464    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.track                #3f4244    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.trackArc             0
 ScrollBar.trackHighlight       #7e7e7e    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.trackInsets          0,0,0,0    javax.swing.plaf.InsetsUIResource [UI]
 ScrollBar.width                10
 ScrollBarUI                    com.formdev.flatlaf.ui.FlatScrollBarUI
 

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/uidefaults/FlatLightLaf_1.8.0_202.txt

@@ -763,17 +763,22 @@ ScrollBar.buttonArrowColor     #666666    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.buttonDisabledArrowColor #ababab    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.foreground           #000000    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.hoverThumbColor      #c3c3c3    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.hoverThumbWithTrack  false
 ScrollBar.hoverTrackColor      #ededed    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.maximumThumbSize     4096,4096    javax.swing.plaf.DimensionUIResource [UI]
 ScrollBar.minimumThumbSize     8,8    javax.swing.plaf.DimensionUIResource [UI]
 ScrollBar.showButtons          false
 ScrollBar.squareButtons        false
 ScrollBar.thumb                #dcdcdc    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.thumbArc             0
 ScrollBar.thumbDarkShadow      #9e9e9e    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.thumbHighlight       #ffffff    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.thumbInsets          0,0,0,0    javax.swing.plaf.InsetsUIResource [UI]
 ScrollBar.thumbShadow          #c4c4c4    javax.swing.plaf.ColorUIResource [UI]
 ScrollBar.track                #f5f5f5    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.trackArc             0
 ScrollBar.trackHighlight       #9e9e9e    javax.swing.plaf.ColorUIResource [UI]
+ScrollBar.trackInsets          0,0,0,0    javax.swing.plaf.InsetsUIResource [UI]
 ScrollBar.width                10
 ScrollBarUI                    com.formdev.flatlaf.ui.FlatScrollBarUI