multi-line ToolTip

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatLaf.java

@@ -411,7 +411,7 @@ public abstract class FlatLaf
 		}
 	}
 
-	private static List<String> split( String str, char delim ) {
+	public static List<String> split( String str, char delim ) {
 		ArrayList<String> strs = new ArrayList<>();
 		int delimIndex = str.indexOf( delim );
 		int index = 0;

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

@@ -0,0 +1,91 @@
+/*
+ * 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.Dimension;
+import java.awt.FontMetrics;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Insets;
+import java.util.List;
+import javax.swing.JComponent;
+import javax.swing.JToolTip;
+import javax.swing.SwingUtilities;
+import javax.swing.plaf.ComponentUI;
+import javax.swing.plaf.basic.BasicToolTipUI;
+import com.formdev.flatlaf.FlatLaf;
+
+/**
+ * Provides the Flat LaF UI delegate for {@link javax.swing.JToolTip}.
+ *
+ * @author Karl Tauber
+ */
+public class FlatToolTipUI
+	extends BasicToolTipUI
+{
+	private static ComponentUI instance;
+
+	public static ComponentUI createUI( JComponent c ) {
+		if( instance == null )
+			instance = new FlatToolTipUI();
+		return instance;
+	}
+
+	@Override
+	public Dimension getPreferredSize( JComponent c ) {
+		if( isMultiLine( c ) ) {
+			FontMetrics fm = c.getFontMetrics( c.getFont() );
+			Insets insets = c.getInsets();
+
+			List<String> lines = FlatLaf.split( ((JToolTip)c).getTipText(), '\n' );
+			int width = 0;
+			int height = fm.getHeight() * Math.max( lines.size(), 1 );
+			for( String line : lines )
+				width = Math.max( width, SwingUtilities.computeStringWidth( fm, line ) );
+
+			return new Dimension( insets.left + width + insets.right, insets.top + height + insets.bottom );
+		} else
+			return super.getPreferredSize( c );
+	}
+
+	@Override
+	public void paint( Graphics g, JComponent c ) {
+		if( isMultiLine( c ) ) {
+			FontMetrics fm = c.getFontMetrics( c.getFont() );
+			Insets insets = c.getInsets();
+
+			FlatUIUtils.setRenderingHints( (Graphics2D) g );
+			g.setColor( c.getForeground() );
+
+			List<String> lines = FlatLaf.split( ((JToolTip)c).getTipText(), '\n' );
+
+			int x = insets.left;
+			int y = insets.top - fm.getDescent();
+			int lineHeight = fm.getHeight();
+			for( String line : lines ) {
+				y += lineHeight;
+				g.drawString( line, x, y );
+			}
+		} else
+			super.paint( g, c );
+	}
+
+	private boolean isMultiLine( JComponent c ) {
+		String text = ((JToolTip)c).getTipText();
+		return c.getClientProperty( "html" ) == null && text != null && text.indexOf( '\n' ) >= 0;
+	}
+}

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

@@ -50,7 +50,7 @@ TextPaneUI=com.formdev.flatlaf.ui.FlatTextPaneUI
 ToggleButtonUI=com.formdev.flatlaf.ui.FlatToggleButtonUI
 ToolBarUI=com.formdev.flatlaf.ui.FlatToolBarUI
 ToolBarSeparatorUI=com.formdev.flatlaf.ui.FlatToolBarSeparatorUI
-ToolTipUI=javax.swing.plaf.basic.BasicToolTipUI
+ToolTipUI=com.formdev.flatlaf.ui.FlatToolTipUI
 TreeUI=com.formdev.flatlaf.ui.FlatTreeUI
 ViewportUI=com.formdev.flatlaf.ui.FlatViewportUI
 

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatComponentsTest.java

@@ -156,6 +156,7 @@ public class FlatComponentsTest
 		indeterminateCheckBox = new JCheckBox();
 		JLabel toolTipLabel = new JLabel();
 		JToolTip toolTip1 = new JToolTip();
+		JToolTip toolTip2 = new JToolTip();
 		JLabel toolBarLabel = new JLabel();
 		JToolBar toolBar1 = new JToolBar();
 		JButton button4 = new JButton();
@@ -775,6 +776,10 @@ public class FlatComponentsTest
 		toolTip1.setTipText("Some text in tool tip.");
 		add(toolTip1, "cell 1 20 3 1");
 
+		//---- toolTip2 ----
+		toolTip2.setTipText("Tool tip with\nmultiple\nlines.");
+		add(toolTip2, "cell 1 20 3 1");
+
 		//---- toolBarLabel ----
 		toolBarLabel.setText("JToolBar:");
 		add(toolBarLabel, "cell 0 21");

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatComponentsTest.jfd

@@ -770,6 +770,12 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 1 20 3 1"
 			} )
+			add( new FormComponent( "javax.swing.JToolTip" ) {
+				name: "toolTip2"
+				"tipText": "Tool tip with\nmultiple\nlines."
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 1 20 3 1"
+			} )
 			add( new FormComponent( "javax.swing.JLabel" ) {
 				name: "toolBarLabel"
 				"text": "JToolBar:"