plugins/ui-designer/src/com/intellij/uiDesigner/designSurface/EventProcessor.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.uiDesigner.designSurface;
  17
  18 import java.awt.*;
  19 import java.awt.event.KeyEvent;
  20 import java.awt.event.MouseEvent;
  21
  22 /**
  23  * @author Anton Katilin
  24  * @author Vladimir Kondratyev
  25  */
  26 public abstract class EventProcessor {
  27   private Cursor myCursor;
  28
  29   public final Cursor getCursor(){
  30     return myCursor;
  31   }
  32
  33   public final void setCursor(final Cursor cursor){
  34     myCursor = cursor;
  35   }
  36
  37   protected abstract void processKeyEvent(KeyEvent e);
  38
  39   protected abstract void processMouseEvent(MouseEvent e);
  40
  41   /**
  42    * @return true if processor cancelled its operation; false otherwise
  43    */
  44   protected abstract boolean cancelOperation();
  45
  46   public boolean isDragActive() {
  47     return false;
  48   }
  49
  50   public boolean needMousePressed() {
  51     return false;
  52   }
  53
  54   protected static ComponentDropLocation.Direction directionFromKey(final int keyCode) {
  55     switch(keyCode) {
  56       case KeyEvent.VK_RIGHT: return ComponentDropLocation.Direction.RIGHT;
  57       case KeyEvent.VK_LEFT: return ComponentDropLocation.Direction.LEFT;
  58       case KeyEvent.VK_UP: return ComponentDropLocation.Direction.UP;
  59       case KeyEvent.VK_DOWN: return ComponentDropLocation.Direction.DOWN;
  60       case KeyEvent.VK_END: return ComponentDropLocation.Direction.RIGHT;
  61       case KeyEvent.VK_HOME: return ComponentDropLocation.Direction.LEFT;
  62       case KeyEvent.VK_PAGE_UP: return ComponentDropLocation.Direction.UP;
  63       case KeyEvent.VK_PAGE_DOWN: return ComponentDropLocation.Direction.DOWN;
  64       default: return null;
  65     }
  66   }
  67
  68   private static boolean isMoveToLast(final int keyCode) {
  69     return keyCode == KeyEvent.VK_HOME || keyCode == KeyEvent.VK_END ||
  70            keyCode == KeyEvent.VK_PAGE_UP || keyCode == KeyEvent.VK_PAGE_DOWN;
  71   }
  72
  73   protected static ComponentDropLocation moveDropLocation(final GuiEditor editor, final ComponentDropLocation location,
  74                                                  final ComponentDragObject dragObject, final KeyEvent e) {
  75     ComponentDropLocation.Direction dir = directionFromKey(e.getKeyCode());
  76     boolean moveToLast = isMoveToLast(e.getKeyCode());
  77     if (dir != null && location != null) {
  78       e.consume();
  79       ComponentDropLocation adjacentLocation;
  80       if (moveToLast) {
  81         adjacentLocation = location.getAdjacentLocation(dir);
  82         ComponentDropLocation lastLocation = location;
  83         while(adjacentLocation != null) {
  84           if (adjacentLocation.canDrop(dragObject)) {
  85             lastLocation = adjacentLocation;
  86           }
  87           adjacentLocation = adjacentLocation.getAdjacentLocation(dir);
  88         }
  89         adjacentLocation = lastLocation;
  90       }
  91       else {
  92         adjacentLocation = location.getAdjacentLocation(dir);
  93         while(adjacentLocation != null && !adjacentLocation.canDrop(dragObject)) {
  94           adjacentLocation = adjacentLocation.getAdjacentLocation(dir);
  95         }
  96       }
  97
  98       if (adjacentLocation != null && adjacentLocation.canDrop(dragObject)) {
  99         adjacentLocation.placeFeedback(editor.getActiveDecorationLayer(), dragObject);
 100         return adjacentLocation;
 101       }
 102     }
 103     return location;
 104   }
 105
 106 }