FlatPropertiesLaf class added that allows creating FlatLaf theme from properties (issue #97)

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

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2020 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
+ *
+ *     https://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;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Properties;
+
+/**
+ * A Flat LaF that is able to load UI defaults from properties passed to the constructor.
+ * <p>
+ * Specify the base theme in the properties with {@code @baseTheme=<baseTheme>}.
+ * Allowed values for {@code <baseTheme>} are {@code light} (the default), {@code dark},
+ * {@code intellij} or {@code darcula}.
+ * <p>
+ * The properties are applied after loading the base theme and may overwrite base properties.
+ * All features of FlatLaf properties files are available.
+ *
+ * @author Karl Tauber
+ */
+public class FlatPropertiesLaf
+	extends FlatLaf
+{
+	private final String name;
+	private final String baseTheme;
+	private final boolean dark;
+	private final Properties properties;
+
+	public FlatPropertiesLaf( String name, File propertiesFile )
+		throws IOException
+	{
+		this( name, new FileInputStream( propertiesFile ) );
+	}
+
+	public FlatPropertiesLaf( String name, InputStream in )
+		throws IOException
+	{
+		this( name, loadProperties( in ) );
+	}
+
+	private static Properties loadProperties( InputStream in )
+		throws IOException
+	{
+		Properties properties = new Properties();
+		try( InputStream in2 = in ) {
+			properties.load( in2 );
+		}
+		return properties;
+	}
+
+	public FlatPropertiesLaf( String name, Properties properties ) {
+		this.name = name;
+		this.properties = properties;
+
+		baseTheme = properties.getProperty( "@baseTheme", "light" );
+		dark = "dark".equalsIgnoreCase( baseTheme ) || "darcula".equalsIgnoreCase( baseTheme );
+	}
+
+	@Override
+	public String getName() {
+		return name;
+	}
+
+	@Override
+	public String getDescription() {
+		return name;
+	}
+
+	@Override
+	public boolean isDark() {
+		return dark;
+	}
+
+	@Override
+	protected ArrayList<Class<?>> getLafClassesForDefaultsLoading() {
+		ArrayList<Class<?>> lafClasses = new ArrayList<>();
+		lafClasses.add( FlatLaf.class );
+		switch( baseTheme.toLowerCase() ) {
+			default:
+			case "light":
+				lafClasses.add( FlatLightLaf.class );
+				break;
+
+			case "dark":
+				lafClasses.add( FlatDarkLaf.class );
+				break;
+
+			case "intellij":
+				lafClasses.add( FlatLightLaf.class );
+				lafClasses.add( FlatIntelliJLaf.class );
+				break;
+
+			case "darcula":
+				lafClasses.add( FlatDarkLaf.class );
+				lafClasses.add( FlatDarculaLaf.class );
+				break;
+		}
+		return lafClasses;
+	}
+
+	@Override
+	protected Properties getAdditionalDefaults() {
+		return properties;
+	}
+}