Button: basic border and background

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

@@ -26,6 +26,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Properties;
 import javax.swing.UIDefaults;
+import javax.swing.UIDefaults.LazyValue;
 import javax.swing.plaf.ColorUIResource;
 import javax.swing.plaf.FontUIResource;
 import javax.swing.plaf.basic.BasicLookAndFeel;
@@ -202,6 +203,10 @@ public abstract class FlatLaf
 			case "true":		return true;
 		}
 
+		// borders
+		if( key.endsWith( ".border" ) )
+			return parseBorder( value );
+
 		// colors
 		ColorUIResource color = parseColor( value );
 		if( color != null )
@@ -211,6 +216,17 @@ public abstract class FlatLaf
 		return value;
 	}
 
+	private Object parseBorder( String value ) {
+		return (LazyValue) t -> {
+			try {
+				return Class.forName( value ).newInstance();
+			} catch( InstantiationException | IllegalAccessException | ClassNotFoundException ex ) {
+				ex.printStackTrace();
+				return null;
+			}
+		};
+	}
+
 	private ColorUIResource parseColor( String value ) {
 		try {
 			if( value.length() == 6 ) {

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

@@ -0,0 +1,87 @@
+/*
+ * 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.Color;
+import java.awt.Component;
+import java.awt.GradientPaint;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Insets;
+import java.awt.Paint;
+import javax.swing.UIManager;
+import javax.swing.plaf.basic.BasicBorders;
+
+/**
+ * Border for {@link javax.swing.JButton}.
+ *
+ * @author Karl Tauber
+ */
+public class FlatButtonBorder
+	extends BasicBorders.MarginBorder
+{
+	@Override
+	public void paintBorder( Component c, Graphics g, int x, int y, int width, int height ) {
+		Graphics2D g2 = (Graphics2D) g.create();
+		try {
+			FlatUIUtils.setRenderingHints( g2 );
+
+			float focusWidth = getFocusWidth();
+			float lineWidth = getLineWidth();
+			float arc = 6; //TODO
+
+			g2.setPaint( getBorderColor( c ) );
+			FlatUIUtils.drawRoundRectangle( g2, x, y, width, height, focusWidth, lineWidth, arc );
+		} finally {
+			g2.dispose();
+		}
+	}
+
+	public Paint getBorderColor( Component c ) {
+		if( c.isEnabled() ) {
+			Color startColor = UIManager.getColor( "Button.startBorderColor" );
+			Color endColor = UIManager.getColor( "Button.endBorderColor" );
+			return (startColor.equals( endColor ) )
+				? startColor
+				: new GradientPaint( 0, getFocusWidth(), startColor,
+					0, c.getHeight() - getFocusWidth() - 1f, endColor );
+		} else
+			return UIManager.getColor( "Button.disabledBorderColor" );
+	}
+
+	@Override
+	public Insets getBorderInsets( Component c, Insets insets ) {
+		int w = Math.round( getFocusWidth() + getLineWidth() );
+
+		insets = super.getBorderInsets( c, insets );
+		insets.top += w;
+		insets.left += w;
+		insets.bottom += w;
+		insets.right += w;
+		return insets;
+	}
+
+	protected float getFocusWidth() {
+		//TODO
+		return 2;
+	}
+
+	protected float getLineWidth() {
+		//TODO
+		return 1;
+	}
+}

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

@@ -0,0 +1,65 @@
+/*
+ * 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.Graphics;
+import java.awt.Graphics2D;
+import javax.swing.JComponent;
+import javax.swing.plaf.ComponentUI;
+import javax.swing.plaf.basic.BasicButtonUI;
+
+/**
+ * Provides the Flat LaF UI delegate for {@link javax.swing.JButton}.
+ *
+ * @author Karl Tauber
+ */
+public class FlatButtonUI
+	extends BasicButtonUI
+{
+	private static ComponentUI instance;
+
+	public static ComponentUI createUI( JComponent c ) {
+		if( instance == null )
+			instance = new FlatButtonUI();
+		return instance;
+	}
+
+	@Override
+	public void update( Graphics g, JComponent c ) {
+		if( c.isOpaque() ) {
+			FlatUIUtils.paintParentBackground( g, c );
+
+			if( c.isEnabled() ) {
+				Graphics2D g2 = (Graphics2D) g.create();
+				try {
+					FlatUIUtils.setRenderingHints( g2 );
+
+					//TODO
+					float focusWidth = 2;
+					float arc = 6;
+
+					g2.setColor( c.getBackground() );
+					FlatUIUtils.fillRoundRectangle( g2, 0, 0, c.getWidth(), c.getHeight(), focusWidth, arc );
+				} finally {
+					g2.dispose();
+				}
+			}
+		}
+
+		paint( g, c );
+	}
+}

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

@@ -0,0 +1,99 @@
+/*
+ * 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.Container;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.RenderingHints;
+import java.awt.geom.Path2D;
+import java.awt.geom.RoundRectangle2D;
+import javax.swing.JComponent;
+
+/**
+ * Utility methods for UI delegates.
+ *
+ * @author Karl Tauber
+ */
+public class FlatUIUtils
+{
+	public static final boolean MAC_USE_QUARTZ = Boolean.getBoolean( "apple.awt.graphics.UseQuartz" );
+
+	/**
+	 * Sets rendering hints used for painting.
+	 */
+	public static void setRenderingHints( Graphics2D g ) {
+		g.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
+		g.setRenderingHint( RenderingHints.KEY_STROKE_CONTROL,
+			MAC_USE_QUARTZ ? RenderingHints.VALUE_STROKE_PURE : RenderingHints.VALUE_STROKE_NORMALIZE );
+	}
+
+	/**
+	 * Draws a round rectangle.
+	 */
+	public static void drawRoundRectangle( Graphics2D g, int x, int y, int width, int height,
+		float focusWidth, float lineWidth, float arc )
+	{
+		float arc2 = arc > lineWidth ? arc - lineWidth : 0f;
+
+		RoundRectangle2D.Float r1 = new RoundRectangle2D.Float(
+			x + focusWidth, y + focusWidth,
+			width - focusWidth * 2, height - focusWidth * 2, arc, arc );
+		RoundRectangle2D.Float r2 = new RoundRectangle2D.Float(
+			r1.x + lineWidth, r1.y + lineWidth,
+			r1.width - lineWidth * 2, r1.height - lineWidth * 2, arc2, arc2 );
+
+		Path2D border = new Path2D.Float( Path2D.WIND_EVEN_ODD );
+		border.append( r1, false );
+		border.append( r2, false );
+		g.fill( border );
+	}
+
+	/**
+	 * Fills a round rectangle.
+	 */
+	public static void fillRoundRectangle( Graphics2D g, int x, int y, int width, int height,
+		float focusWidth, float arc )
+	{
+		g.fill( new RoundRectangle2D.Float(
+			x + focusWidth, y + focusWidth,
+			width - focusWidth * 2, height - focusWidth * 2, arc, arc ) );
+	}
+
+	/**
+	 * Fill background with parent's background color because the visible component
+	 * is smaller than its bounds (for the focus decoration).
+	 */
+	public static void paintParentBackground( Graphics g, JComponent c ) {
+		Container parent = findOpaqueParent( c );
+		if( parent != null ) {
+			g.setColor( parent.getBackground() );
+			g.fillRect( 0, 0, c.getWidth(), c.getHeight() );
+		}
+	}
+
+	/**
+	 * Find the first parent that is opaque.
+	 */
+	private static Container findOpaqueParent( Container c ) {
+		while( (c = c.getParent()) != null ) {
+			if( c.isOpaque() )
+				return c;
+		}
+		return null;
+	}
+}

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

@@ -42,6 +42,15 @@ textText=@foreground
 window=@background
 
 
+#---- Button ----
+
+Button.background=4c5052
+
+Button.startBorderColor=5e6060
+Button.endBorderColor=5e6060
+Button.disabledBorderColor=5e6060
+
+
 #---- Label ----
 
 Label.disabledForeground=808080

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

@@ -16,4 +16,10 @@
 
 #---- UI delegates ----
 
+ButtonUI=com.formdev.flatlaf.ui.FlatButtonUI
 LabelUI=com.formdev.flatlaf.ui.FlatLabelUI
+
+
+#---- Button ----
+
+Button.border=com.formdev.flatlaf.ui.FlatButtonBorder

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

@@ -42,6 +42,15 @@ textText=@foreground
 window=@background
 
 
+#---- Button ----
+
+Button.background=ffffff
+
+Button.startBorderColor=bfbfbf
+Button.endBorderColor=b3b3b3
+Button.disabledBorderColor=cfcfcf
+
+
 #---- Label ----
 
 Label.disabledForeground=777777