added task list editor date cell factory

src/main/java/ch/zhaw/gartenverwaltung/TaskFormularController.java

@@ -1,14 +1,22 @@
 package ch.zhaw.gartenverwaltung;
 
 import ch.zhaw.gartenverwaltung.types.Crop;
+import ch.zhaw.gartenverwaltung.types.GrowthPhaseType;
 import ch.zhaw.gartenverwaltung.types.Task;
 import javafx.fxml.FXML;
+import javafx.fxml.Initializable;
+import javafx.scene.control.DateCell;
 import javafx.scene.control.DatePicker;
 import javafx.scene.control.TextArea;
 import javafx.scene.control.TextField;
+import javafx.util.Callback;
 
-public class TaskFormularController {
-    Crop crop;
+import java.net.URL;
+import java.time.LocalDate;
+import java.util.ResourceBundle;
+
+public class TaskFormularController implements Initializable {
+    private Crop crop;
 
     @FXML
     private TextArea description_area;
@@ -44,4 +52,32 @@ public class TaskFormularController {
         end_datePicker.setValue(task.getEndDate().get());
         interval_field.setText(task.getInterval().get().toString());
     }
+
+    private Callback<DatePicker, DateCell> getDayCellFactory() {
+
+        return (datePicker) -> new DateCell() {
+            private final LocalDate today = LocalDate.now();
+
+            @Override
+            public void updateItem(LocalDate item, boolean empty) {
+                super.updateItem(item, empty);
+                setDisable(true);
+                setStyle("-fx-background-color: #ffc0cb;");
+
+                if (item.compareTo(today) > 0 && item.compareTo(crop.getStartDate()) > 0) {
+                    setDisable(false);
+                    setStyle("-fx-background-color: #32CD32;");
+                }
+            }
+        };
+    }
+
+    @Override
+    public void initialize(URL location, ResourceBundle resources) {
+        start_datePicker.setDayCellFactory(getDayCellFactory());
+        start_datePicker.setEditable(false);
+
+        end_datePicker.setDayCellFactory(getDayCellFactory());
+        end_datePicker.setEditable(false);
+    }
 }