Set current image data (#41)

src/main/java/qupath/ext/instanseg/core/InstanSeg.java

@@ -11,6 +11,7 @@
 import qupath.lib.objects.PathObject;
 import qupath.lib.plugins.TaskRunner;
 import qupath.lib.plugins.TaskRunnerUtils;
+import qupath.lib.scripting.QP;
 
 import java.awt.image.BufferedImage;
 import java.io.IOException;
@@ -158,6 +159,16 @@ public Builder imageData(ImageData<BufferedImage> imageData) {
             return this;
         }
 
+        /**
+         * Set the imageData to be used as the current image data.
+         * @return A modified builder
+         */
+        public Builder currentImageData() {
+            this.imageData = QP.getCurrentImageData();
+            return this;
+        }
+
+
         /**
          * Set the channels to be used in inference
          * @param channels A collection of channels to be used in inference
@@ -369,10 +380,10 @@ public Builder outputAnnotations() {
          */
         public InstanSeg build() {
             if (imageData == null) {
-                throw new IllegalStateException("imageData cannot be null!");
+                // assignment is just to suppress IDE suggestion for void return
+                var tmp = currentImageData();
             }
             if (channels == null) {
-                // assignment is just to suppress IDE suggestion for void return
                 var tmp = allChannels();
             }
             if (outputClasses == null) {