Merge pull request #4354 from paulkaplan/fix-backpack-sprite

Fix issue where you couldn't add sprites from backpack when there are no sprites

src/containers/costume-tab.jsx

@@ -206,7 +206,7 @@ class CostumeTab extends React.Component {
         this.fileInput.click();
     }
     handleDrop (dropInfo) {
-        if (dropInfo.dragType === DragConstants.COSTUME) {
+        if (dropInfo.dragType === DragConstants.COSTUME && dropInfo.newIndex !== null) {
             const sprite = this.props.vm.editingTarget.sprite;
             const activeCostume = sprite.costumes[this.state.selectedCostumeIndex];
             this.props.vm.reorderCostume(this.props.vm.editingTarget.id,

src/containers/sound-tab.jsx

@@ -130,7 +130,7 @@ class SoundTab extends React.Component {
     }
 
     handleDrop (dropInfo) {
-        if (dropInfo.dragType === DragConstants.SOUND) {
+        if (dropInfo.dragType === DragConstants.SOUND && dropInfo.newIndex !== null) {
             const sprite = this.props.vm.editingTarget.sprite;
             const activeSound = sprite.sounds[this.state.selectedSoundIndex];
 

src/containers/target-pane.jsx

@@ -163,7 +163,7 @@ class TargetPane extends React.Component {
     }
     handleDrop (dragInfo) {
         const {sprite: targetId} = this.props.hoveredTarget;
-        if (dragInfo.dragType === DragConstants.SPRITE) {
+        if (dragInfo.dragType === DragConstants.SPRITE && dragInfo.newIndex !== null) {
             // Add one to both new and target index because we are not counting/moving the stage
             this.props.vm.reorderTarget(dragInfo.index + 1, dragInfo.newIndex + 1);
         } else if (dragInfo.dragType === DragConstants.BACKPACK_SPRITE) {

src/lib/sortable-hoc.jsx

@@ -33,10 +33,9 @@ const SortableHOC = function (WrappedComponent) {
                 }
                 this.containerBox = this.ref.getBoundingClientRect();
             } else if (!newProps.dragInfo.dragging && this.props.dragInfo.dragging) {
-                const newIndex = this.getMouseOverIndex();
-                if (newIndex !== null) {
-                    this.props.onDrop(Object.assign({}, this.props.dragInfo, {newIndex}));
-                }
+                this.props.onDrop(Object.assign({}, this.props.dragInfo, {
+                    newIndex: this.getMouseOverIndex()
+                }));
             }
         }