implements #64

demo/app/app.css

@@ -17,6 +17,9 @@
     color: green;
     text-align: right;
 }
+.default:disabled {
+    opacity: 0.5
+}
 
 StackLayout {
     horizontal-align: center;

demo/app/main-page.ts

@@ -21,6 +21,7 @@ export function pageLoaded(args: EventData) {
     viewModel.set("items", items);
     viewModel.set("hint", "My Hint");
     viewModel.set("selectedIndex", null);    
+    viewModel.set("isEnabled", true);    
     viewModel.set("cssClass", "default");
 
     page.bindingContext = viewModel;

demo/app/main-page.xml

@@ -1,13 +1,18 @@
 <Page xmlns="http://schemas.nativescript.org/tns.xsd" loaded="pageLoaded" xmlns:dd="nativescript-drop-down">
-  <GridLayout rows="auto, auto, auto, auto, auto, *" columns="auto, *">
+  <GridLayout rows="auto, auto, auto, auto, auto, auto, *" columns="auto, *">
     <dd:DropDown id="dd" hint="{{ hint }}" items="{{ items }}" selectedIndex="{{ selectedIndex }}" 
                   opened="dropDownOpened" closed="dropDownClosed" selectedIndexChanged="dropDownSelectedIndexChanged" 
-                  class="{{ cssClass }}"
-                  row="0" colSpan="2" />                 
+                  class="{{ cssClass }}" isEnabled="{{ isEnabled }}"
+                  row="0" colSpan="2" /> 
+
     <Label text="Selected Index:" row="1" col="0" fontSize="18" verticalAlignment="bottom"/>
     <TextField text="{{ selectedIndex }}" row="1" col="1" />
-    <Button row="2" col="0" colSpan="2" tap="changeStyles" text="Change Styles" style="font-size: 25" />
-    <Button row="3" col="0" colSpan="2" tap="open" text="Open" style="font-size: 25" />
-    <Button row="4" col="0" colSpan="2" tap="close" text="Close" style="font-size: 25" />
+
+    <Label text="Enabled?" row="2" col="0" fontSize="18" verticalAlignment="bottom"/>
+    <Switch checked="{{ isEnabled }}" row="2" col="1" horizontalAlignment="left" />
+
+    <Button row="3" col="0" colSpan="2" tap="changeStyles" text="Change Styles" style="font-size: 25" />
+    <Button row="4" col="0" colSpan="2" tap="open" text="Open" style="font-size: 25" />
+    <Button row="5" col="0" colSpan="2" tap="close" text="Close" style="font-size: 25" />
   </GridLayout>
 </Page>

drop-down.android.ts

@@ -105,7 +105,9 @@ export class DropDown extends DropDownBase {
     }
 
     public open() {
-        this.nativeView.performClick();
+        if (this.isEnabled) {
+            this.nativeView.performClick();
+        }    
     }
 
     public close() {

drop-down.ios.ts

@@ -127,7 +127,9 @@ export class DropDown extends DropDownBase {
     }
 
     public open() {
-        this.ios.becomeFirstResponder();
+        if (this.isEnabled) {
+            this.ios.becomeFirstResponder();
+        }    
     }
 
     public close() {
@@ -510,7 +512,11 @@ class TNSDropDownLabel extends TNSLabel {
     @ObjCMethod()
     public tap( @ObjCParam(UITapGestureRecognizer) sender: UITapGestureRecognizer) {
         if (sender.state === UIGestureRecognizerState.Ended) {
-            this.becomeFirstResponder();
+            const owner = this._owner.get();
+
+            if (owner.isEnabled) {
+                this.becomeFirstResponder();
+            }    
         }    
     }