python/educational-core/student/src/com/jetbrains/edu/learning/actions/StudyPrevWindowAction.java

   1 package com.jetbrains.edu.learning.actions;
   2
   3 import com.jetbrains.edu.courseFormat.AnswerPlaceholder;
   4 import com.jetbrains.edu.learning.StudyUtils;
   5 import icons.InteractiveLearningIcons;
   6 import org.jetbrains.annotations.NotNull;
   7 import org.jetbrains.annotations.Nullable;
   8
   9 import java.util.List;
  10
  11 /**
  12  * author: liana
  13  * data: 6/30/14.
  14  */
  15 public class StudyPrevWindowAction extends StudyWindowNavigationAction {
  16   public static final String ACTION_ID = "PrevWindowAction";
  17   public static final String SHORTCUT = "ctrl shift pressed COMMA";
  18
  19   public StudyPrevWindowAction() {
  20     super("Navigate to the Previous Answer Placeholder", "Navigate to the previous answer placeholder", InteractiveLearningIcons.Prev);
  21   }
  22
  23
  24   @Nullable
  25   @Override
  26   protected AnswerPlaceholder getNextAnswerPlaceholder(@NotNull final AnswerPlaceholder window) {
  27     int prevIndex = window.getIndex() - 1;
  28     List<AnswerPlaceholder> windows = window.getTaskFile().getAnswerPlaceholders();
  29     if (StudyUtils.indexIsValid(prevIndex, windows)) {
  30       return windows.get(prevIndex);
  31     }
  32     return null;
  33   }
  34 }