Add API to store any type of data in the dataTransfer object (#9319)

3 files changed, 55 insertions, 25 deletions

diff --git a/client/src/main/java/com/vaadin/client/connectors/grid/GridDropTargetConnector.java b/client/src/main/java/com/vaadin/client/connectors/grid/GridDropTargetConnector.java
index cc84392156..2ee5c253a9 100644
--- a/client/src/main/java/com/vaadin/client/connectors/grid/GridDropTargetConnector.java
+++ b/client/src/main/java/com/vaadin/client/connectors/grid/GridDropTargetConnector.java
@@ -15,6 +15,8 @@
  */
 package com.vaadin.client.connectors.grid;
 
+import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
 
@@ -81,8 +83,9 @@ public class GridDropTargetConnector extends DropTargetExtensionConnector {
     }
 
     @Override
-    protected void sendDropEventToServer(String dataTransferText,
-            String dropEffect, NativeEvent dropEvent) {
+    protected void sendDropEventToServer(List<String> types,
+            Map<String, String> data, String dropEffect,
+            NativeEvent dropEvent) {
 
         String rowKey = null;
         DropLocation dropLocation = null;
@@ -95,7 +98,7 @@ public class GridDropTargetConnector extends DropTargetExtensionConnector {
             dropLocation = getDropLocation(targetRow.get(), dropEvent);
         }
 
-        getRpcProxy(GridDropTargetRpc.class).drop(dataTransferText, dropEffect,
+        getRpcProxy(GridDropTargetRpc.class).drop(types, data, dropEffect,
                 rowKey, dropLocation);
     }
 
diff --git a/client/src/main/java/com/vaadin/client/extensions/DragSourceExtensionConnector.java b/client/src/main/java/com/vaadin/client/extensions/DragSourceExtensionConnector.java
index d714cf4016..552ff151cd 100644
--- a/client/src/main/java/com/vaadin/client/extensions/DragSourceExtensionConnector.java
+++ b/client/src/main/java/com/vaadin/client/extensions/DragSourceExtensionConnector.java
@@ -15,6 +15,9 @@
  */
 package com.vaadin.client.extensions;
 
+import java.util.List;
+import java.util.Map;
+
 import com.google.gwt.animation.client.AnimationScheduler;
 import com.google.gwt.dom.client.DataTransfer;
 import com.google.gwt.dom.client.Element;
@@ -182,14 +185,22 @@ public class DragSourceExtensionConnector extends AbstractExtensionConnector {
         // Set drag image
         setDragImage(nativeEvent);
 
-        // Set text data parameter
-        String dataTransferText = createDataTransferText(nativeEvent);
+        // Set data parameters
+        List<String> types = getState().types;
+        Map<String, String> data = getState().data;
+        for (String type : types) {
+            nativeEvent.getDataTransfer().setData(type, data.get(type));
+        }
+
         // Always set something as the text data, or DnD won't work in FF !
+        String dataTransferText = createDataTransferText(nativeEvent);
         if (dataTransferText == null) {
             dataTransferText = "";
         }
-        nativeEvent.getDataTransfer().setData(DragSourceState.DATA_TYPE_TEXT,
-                dataTransferText);
+
+        // Override data type "text" when storing special data is needed
+        nativeEvent.getDataTransfer()
+                .setData(DragSourceState.DATA_TYPE_TEXT, dataTransferText);
 
         // Initiate firing server side dragstart event when there is a
         // DragStartListener attached on the server side
@@ -252,7 +263,7 @@ public class DragSourceExtensionConnector extends AbstractExtensionConnector {
      * @return Textual data to be set for the event or {@literal null}.
      */
     protected String createDataTransferText(NativeEvent dragStartEvent) {
-        return getState().dataTransferText;
+        return getState().data.get(DragSourceState.DATA_TYPE_TEXT);
     }
 
     /**
diff --git a/client/src/main/java/com/vaadin/client/extensions/DropTargetExtensionConnector.java b/client/src/main/java/com/vaadin/client/extensions/DropTargetExtensionConnector.java
index 0f3d6413cb..060f2a5167 100644
--- a/client/src/main/java/com/vaadin/client/extensions/DropTargetExtensionConnector.java
+++ b/client/src/main/java/com/vaadin/client/extensions/DropTargetExtensionConnector.java
@@ -15,6 +15,12 @@
  */
 package com.vaadin.client.extensions;
 
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import com.google.gwt.core.client.JsArrayString;
 import com.google.gwt.dom.client.DataTransfer;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.dom.client.NativeEvent;
@@ -24,7 +30,6 @@ import com.vaadin.client.ComponentConnector;
 import com.vaadin.client.ServerConnector;
 import com.vaadin.client.ui.AbstractComponentConnector;
 import com.vaadin.shared.ui.Connect;
-import com.vaadin.shared.ui.dnd.DragSourceState;
 import com.vaadin.shared.ui.dnd.DropEffect;
 import com.vaadin.shared.ui.dnd.DropTargetRpc;
 import com.vaadin.shared.ui.dnd.DropTargetState;
@@ -257,13 +262,18 @@ public class DropTargetExtensionConnector extends AbstractExtensionConnector {
             nativeEvent.preventDefault();
             nativeEvent.stopPropagation();
 
-            String dataTransferText = nativeEvent.getDataTransfer()
-                    .getData(DragSourceState.DATA_TYPE_TEXT);
-
-            String dropEffect = DragSourceExtensionConnector
-                    .getDropEffect(nativeEvent.getDataTransfer());
-
-            sendDropEventToServer(dataTransferText, dropEffect, nativeEvent);
+            JsArrayString typesJsArray = getTypes(
+                    nativeEvent.getDataTransfer());
+            List<String> types = new ArrayList<>();
+            Map<String, String> data = new HashMap<>();
+            for (int i = 0; i < typesJsArray.length(); i++) {
+                String type = typesJsArray.get(i);
+                types.add(type);
+                data.put(type, nativeEvent.getDataTransfer().getData(type));
+            }
+
+            sendDropEventToServer(types, data, DragSourceExtensionConnector
+                    .getDropEffect(nativeEvent.getDataTransfer()), nativeEvent);
         }
 
         removeTargetClassIndicator(nativeEvent);
@@ -291,17 +301,18 @@ public class DropTargetExtensionConnector extends AbstractExtensionConnector {
     /**
      * Initiates a server RPC for the drop event.
      *
-     * @param dataTransferText
-     *            Client side textual data that can be set for the drag source
-     *            and is transferred to the drop target.
+     * @param types
+     *         List of data types from {@code DataTransfer.types} object.
+     * @param data
+     *         Map containing all types and corresponding data from the {@code
+     *         DataTransfer} object.
      * @param dropEffect
-     *            the desired drop effect
-     * @param dropEvent
-     *            Client side drop event.
+     *         The desired drop effect.
      */
-    protected void sendDropEventToServer(String dataTransferText,
-            String dropEffect, NativeEvent dropEvent) {
-        getRpcProxy(DropTargetRpc.class).drop(dataTransferText, dropEffect);
+    protected void sendDropEventToServer(List<String> types,
+            Map<String, String> data, String dropEffect,
+            NativeEvent dropEvent) {
+        getRpcProxy(DropTargetRpc.class).drop(types, data, dropEffect);
     }
 
     /**
@@ -337,6 +348,11 @@ public class DropTargetExtensionConnector extends AbstractExtensionConnector {
         getDropTargetElement().removeClassName(styleDragCenter);
     }
 
+    private native JsArrayString getTypes(DataTransfer dataTransfer)
+    /*-{
+        return dataTransfer.types;
+    }-*/;
+
     private native boolean executeScript(NativeEvent event, String script)
     /*-{
         return new Function('event', script)(event);