Combobox - Added new property dropdownParent() to easily update where is the dropdown to be placed.

Added JUnit test to new property dropdownParent() on ComboBox.

Author: kevzlou7979

src/main/java/gwt/material/design/addins/client/combobox/MaterialComboBox.java

@@ -101,6 +101,7 @@ public class MaterialComboBox<T> extends AbstractValueWidget<List<T>> implements
     private boolean hideSearch;
     private int limit;
     private boolean closeOnSelect = true;
+    private String dropdownParent = "body";
     private boolean suppressChangeEvent;
 
     private int selectedIndex;
@@ -150,6 +151,7 @@ protected void initialize() {
         options.placeholder = placeholder;
         options.maximumSelectionLength = limit;
         options.closeOnSelect = closeOnSelect;
+        options.dropdownParent = $(dropdownParent);
 
         if (clearInputHandler == null) {
             clearInputHandler = addSelectionHandler(valueChangeEvent -> $(getElement()).find("input").val(""));
@@ -227,6 +229,17 @@ public void add(Widget child) {
         listbox.add(child);
     }
 
+    /**
+    * Sets the parent element of the dropdown
+    */
+    public void setDropdownParent(String dropdownParent) {
+        this.dropdownParent = dropdownParent;
+    }
+
+    public String getDropdownParent() {
+        return dropdownParent;
+    }
+
     /**
      * Sets multi-value select boxes.
      */

src/main/java/gwt/material/design/addins/client/combobox/js/JsComboBoxOptions.java

@@ -19,6 +19,7 @@
  */
 package gwt.material.design.addins.client.combobox.js;
 
+import gwt.material.design.jquery.client.api.JQueryElement;
 import jsinterop.annotations.JsPackage;
 import jsinterop.annotations.JsProperty;
 import jsinterop.annotations.JsType;
@@ -34,6 +35,9 @@ public class JsComboBoxOptions {
     @JsProperty
     public String placeholder;
 
+    @JsProperty
+    public JQueryElement dropdownParent;
+
     @JsProperty
     public boolean allowClear;
 

src/test/java/gwt/material/design/addins/client/MaterialComboBoxTest.java

@@ -109,6 +109,12 @@ protected <T extends MaterialComboBox<User>> void checkProperties(T comboBox) {
         assertEquals(comboBox.getLabel().getText(), "label");
         comboBox.setPlaceholder("placeholder");
         assertEquals(comboBox.getPlaceholder(), "placeholder");
+
+        final String BODY_SELECTOR = "body";
+        final String SELF_SELECTOR = "#" + comboBox.getElement().getId();
+        assertEquals(comboBox.getDropdownParent(), BODY_SELECTOR);
+        comboBox.setDropdownParent(SELF_SELECTOR);
+        assertEquals(comboBox.getDropdownParent(), SELF_SELECTOR);
     }
 
     protected <T extends MaterialComboBox> void checkEvents(T comboBox) {