Merge pull request vincenzopalazzo#199 from juanmuscaria/master

Make swingx/MaterialTaskPaneUI optional

README.md

@@ -77,6 +77,12 @@ dependencies {
 
 ```
 
+### Excluding Swingx
+
+While swingx is a transitive dependency for Material-UI-Swing, it is not strictly required for it to work.
+Projects that wish to exclude it can use dependency exclusion on [Maven](https://maven.apache.org/guides/introduction/introduction-to-optional-and-excludes-dependencies.html)
+or [Gradle](https://docs.gradle.org/current/userguide/dependency_downgrade_and_exclude.html#sec:excluding-transitive-deps).
+
 ## Code Style
 > We live in a world where robots can drive a car, so we shouldn't just write code, we should write elegant code.
 

src/main/java/mdlaf/MaterialLookAndFeel.java

@@ -113,7 +113,7 @@ public class MaterialLookAndFeel extends MetalLookAndFeel {
   private static final String separatorUI = MaterialSeparatorUI.class.getCanonicalName();
   private static final String fileChooserUI = MaterialFileChooserUI.class.getCanonicalName();
   private static final String toolTipUI = MaterialToolTipUI.class.getCanonicalName();
-  private static final String taskPaneUI = MaterialTaskPaneUI.class.getCanonicalName();
+  private static final String taskPaneUI;
   private static final String formattedTextFieldUI =
       MaterialFormattedTextFieldUI.class.getCanonicalName();
   private static final String listUI = MaterialListUI.class.getCanonicalName();
@@ -125,6 +125,16 @@ public class MaterialLookAndFeel extends MetalLookAndFeel {
   private static final String colorChooserUI = MaterialColorChooser.class.getCanonicalName();
   private static final String splitPaneUI = MaterialSplitPaneUI.class.getCanonicalName();
 
+  static {
+    String taskPaneUIName = null;
+    try {
+      taskPaneUIName = MaterialTaskPaneUI.class.getCanonicalName();
+    } catch (NoClassDefFoundError ignored) {
+      // Swingx is not in the classpath
+    }
+    taskPaneUI = taskPaneUIName;
+  }
+
   public static void changeTheme(MaterialTheme theme) {
     if (theme == null) {
       return;
@@ -235,7 +245,9 @@ protected void initClassDefaults(UIDefaults table) {
     table.put("SplitPaneUI", splitPaneUI);
     table.put("ColorChooserUI", colorChooserUI);
     // java swingx
-    table.put("swingx/TaskPaneUI", taskPaneUI);
+    if (taskPaneUI != null) {
+      table.put("swingx/TaskPaneUI", taskPaneUI);
+    }
   }
 
   @Override