Add option to change the shared ThemeSettingsPanel.

core/src/main/java/com/github/weisj/darklaf/settings/ThemeSettings.java

@@ -41,6 +41,7 @@ import com.github.weisj.darklaf.theme.info.PreferredThemeStyle;
 import com.github.weisj.darklaf.util.DarkUIUtil;
 import com.github.weisj.darklaf.util.LazyValue;
 import com.github.weisj.darklaf.util.LogUtil;
+import com.github.weisj.darklaf.util.MutableLazyValue;
 
 public class ThemeSettings implements ThemePreferenceListener {
 
@@ -48,7 +49,7 @@ public class ThemeSettings implements ThemePreferenceListener {
     private static final LazyValue<ThemeSettings> instance = new LazyValue<>(ThemeSettings::new);
     private static final LazyValue<Icon> icon = new LazyValue<>(() -> UIManager.getIcon("ThemeSettings.icon"));
 
-    private final LazyValue<ThemeSettingsPanel> settingsPanel;
+    private final MutableLazyValue<ThemeSettingsPanel> settingsPanel;
 
     private JDialog dialog;
 
@@ -88,7 +89,7 @@ public class ThemeSettings implements ThemePreferenceListener {
         LafManager.addThemePreferenceChangeListener(this);
         currentConfiguration = new DefaultSettingsConfiguration();
         savedConfiguration = new DefaultSettingsConfiguration();
-        settingsPanel = new LazyValue<>(() -> {
+        settingsPanel = new MutableLazyValue<>(() -> {
             ThemeSettingsPanel panel = new ThemeSettingsPanel();
             panel.loadConfiguration(currentConfiguration);
             return panel;
@@ -147,6 +148,18 @@ public class ThemeSettings implements ThemePreferenceListener {
         return settingsPanel.get();
     }
 
+    /**
+     * Set the shared {@link ThemeSettingsPanel}.
+     *
+     * @param panel the @link ThemeSettingsPanel}.
+     */
+    public void setThemeSettingsPanel(final ThemeSettingsPanel panel) {
+        if (panel != null) {
+            settingsPanel.set(panel);
+            panel.loadConfiguration(currentConfiguration);
+        }
+    }
+
     /**
      * Returns whether the option to follow the system settings is enabled.
      *

utils/src/main/java/com/github/weisj/darklaf/util/LazyValue.java

@@ -51,6 +51,10 @@ public class LazyValue<T> {
         return value;
     }
 
+    protected void set(final T value) {
+        this.value = value;
+    }
+
     public void ifPresent(final Consumer<T> action) {
         if (isInitialized() && value != null) {
             action.accept(value);
@@ -64,7 +68,7 @@ public class LazyValue<T> {
     }
 
     public T get() {
-        if (value == null) value = load();
+        if (value == null) set(load());
         return value;
     }
 }

utils/src/main/java/com/github/weisj/darklaf/util/MutableLazyValue.java

@@ -0,0 +1,40 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 Jannis Weis
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+ * associated documentation files (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge, publish, distribute,
+ * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+ * NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+package com.github.weisj.darklaf.util;
+
+import java.util.function.Supplier;
+
+public class MutableLazyValue<T> extends LazyValue<T> {
+
+
+    public MutableLazyValue(final T value) {
+        super(value);
+    }
+
+    public MutableLazyValue(final Supplier<T> supplier) {
+        super(supplier);
+    }
+
+    public void set(final T value) {
+        super.set(value);
+    }
+}