From 40a2603e56151261c015d304bb9ca05123358b6c Mon Sep 17 00:00:00 2001
From: Karl Tauber <karl@jformdesigner.com>
Date: Tue, 3 Sep 2019 17:04:45 +0200
Subject: [PATCH] Viewport implementation

---
 .../formdev/flatlaf/ui/FlatViewportUI.java    | 55 +++++++++++++++++++
 .../com/formdev/flatlaf/FlatLaf.properties    |  1 +
 2 files changed, 56 insertions(+)
 create mode 100644 flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatViewportUI.java

diff --git a/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatViewportUI.java b/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatViewportUI.java
new file mode 100644
index 00000000..950ae132
--- /dev/null
+++ b/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatViewportUI.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2019 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.ui;
+
+import java.awt.Component;
+import java.awt.Graphics;
+import javax.swing.JComponent;
+import javax.swing.JTable;
+import javax.swing.JViewport;
+import javax.swing.plaf.ComponentUI;
+import javax.swing.plaf.basic.BasicViewportUI;
+
+/**
+ * Provides the Flat LaF UI delegate for {@link javax.swing.JViewport}.
+ *
+ * @author Karl Tauber
+ */
+public class FlatViewportUI
+	extends BasicViewportUI
+{
+	private static ComponentUI instance;
+
+	public static ComponentUI createUI( JComponent c ) {
+		if( instance == null )
+			instance = new FlatViewportUI();
+		return instance;
+	}
+
+	@Override
+	public void update( Graphics g, JComponent c ) {
+		Component view = ((JViewport)c).getView();
+		if( c.isOpaque() && view instanceof JTable ) {
+			// paint viewport background in same color as table background
+			g.setColor( view.getBackground() );
+			g.fillRect( 0, 0, c.getWidth(), c.getHeight() );
+
+			paint( g, c );
+		} else
+			super.update( g, c );
+	}
+}
diff --git a/flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties b/flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties
index 9145c0ad..ad6df996 100644
--- a/flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties
+++ b/flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties
@@ -46,6 +46,7 @@ TextAreaUI=com.formdev.flatlaf.ui.FlatTextAreaUI
 TextFieldUI=com.formdev.flatlaf.ui.FlatTextFieldUI
 TextPaneUI=com.formdev.flatlaf.ui.FlatTextPaneUI
 TreeUI=com.formdev.flatlaf.ui.FlatTreeUI
+ViewportUI=com.formdev.flatlaf.ui.FlatViewportUI
 
 
 #---- variables ----