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11 package org.eclipse.pde.internal.ui.editor;
12 import java.util.List  ;
13 import java.util.Vector ;
14
15 import org.eclipse.jface.action.IAction;
16 import org.eclipse.osgi.util.NLS;
17 import org.eclipse.pde.core.IModelChangeProvider;
18 import org.eclipse.pde.core.IModelChangedEvent;
19 import org.eclipse.pde.core.IModelChangedListener;
20 import org.eclipse.pde.internal.ui.PDEUIMessages;
21 import org.eclipse.ui.forms.editor.IFormPage;
22
23 public abstract class ModelUndoManager
24 implements IModelUndoManager, IModelChangedListener {
25 private boolean ignoreChanges;
26 private List operations;
27 private int undoLevelLimit = 10;
28 private int cursor = -1;
29 private IAction undoAction;
30 private IAction redoAction;
31 private PDEFormEditor editor;
32
33 public ModelUndoManager(PDEFormEditor editor) {
34 this.editor = editor;
35 operations = new Vector ();
36 }
37
38
41 public void connect(IModelChangeProvider provider) {
42 provider.addModelChangedListener(this);
43 if (operations==null) initialize();
44 }
45
46
49 public void disconnect(IModelChangeProvider provider) {
50 provider.removeModelChangedListener(this);
51 }
52
53 private void initialize() {
54 operations = new Vector ();
55 cursor = -1;
56 updateActions();
57 }
58
59
62 public boolean isUndoable() {
63 return cursor>=0;
64 }
65
66
69 public boolean isRedoable() {
70 if (operations == null) initialize();
71 return (cursor+1)<operations.size();
72 }
73
74
77 public void undo() {
78 IModelChangedEvent op = getCurrentOperation();
79 if (op==null) return;
80 ignoreChanges = true;
81 openRelatedPage(op);
82 execute(op, true);
83 cursor --;
84 updateActions();
85 ignoreChanges = false;
86 }
87
88
91 public void redo() {
92 cursor ++;
93 IModelChangedEvent op = getCurrentOperation();
94 if (op==null) return;
95 ignoreChanges = true;
96 openRelatedPage(op);
97 execute(op, false);
98 ignoreChanges = false;
99 updateActions();
100 }
101
102 protected abstract String getPageId(Object object);
103
104 protected abstract void execute(IModelChangedEvent op, boolean undo);
105
106 private void openRelatedPage(IModelChangedEvent op) {
107 Object obj = op.getChangedObjects()[0];
108 String pageId = getPageId(obj);
109 if (pageId!=null) {
110 IFormPage cpage = editor.getActivePageInstance();
111 IFormPage newPage = editor.findPage(pageId);
112 if (cpage != newPage)
113 editor.setActivePage(newPage.getId());
114 }
115 }
116
117
120 public void modelChanged(IModelChangedEvent event) {
121 if (ignoreChanges)
122 return;
123
124 if (event.getChangeType()==IModelChangedEvent.WORLD_CHANGED) {
125 initialize();
126 return;
127 }
128 addOperation(event);
129 }
130
131 private IModelChangedEvent getCurrentOperation() {
132 if (cursor == -1 || cursor == operations.size()) return null;
133 return (IModelChangedEvent)operations.get(cursor);
134 }
135
136 private IModelChangedEvent getNextOperation() {
137 int peekCursor = cursor+1;
138 if (peekCursor >= operations.size()) return null;
139 return (IModelChangedEvent)operations.get(peekCursor);
140 }
141
142 private void addOperation(IModelChangedEvent operation) {
143 operations.add(operation);
144 int size = operations.size();
145 if (size > undoLevelLimit) {
146 int extra = size-undoLevelLimit;
147 for (int i=0; i<extra; i++) {
149 operations.remove(i);
150 }
151 }
152 cursor = operations.size() -1;
153 updateActions();
154 }
155
156 public void setActions(IAction undoAction, IAction redoAction) {
157 this.undoAction = undoAction;
158 this.redoAction = redoAction;
159 updateActions();
160 }
161
162 private void updateActions() {
163 if (undoAction!=null && redoAction!=null) {
164 undoAction.setEnabled(isUndoable());
165 undoAction.setText(getUndoText());
166 redoAction.setEnabled(isRedoable());
167 redoAction.setText(getRedoText());
168 }
169 }
170
171 private String getUndoText() {
172 IModelChangedEvent op = getCurrentOperation();
173 if (op == null) {
174 return PDEUIMessages.UpdateManager_noUndo;
175 }
176 return NLS.bind(PDEUIMessages.UpdateManager_undo, getOperationText(op));
177 }
178
179 private String getRedoText() {
180 IModelChangedEvent op = getNextOperation();
181 if (op == null) {
182 return PDEUIMessages.UpdateManager_noRedo;
183 }
184 return NLS.bind(PDEUIMessages.UpdateManager_redo, getOperationText(op));
185 }
186
187 private String getOperationText(IModelChangedEvent op) {
188 String opText=""; switch (op.getChangeType()) {
190 case IModelChangedEvent.INSERT:
191 opText = PDEUIMessages.UpdateManager_op_add;
192 break;
193 case IModelChangedEvent.REMOVE:
194 opText = PDEUIMessages.UpdateManager_op_remove;
195 break;
196 case IModelChangedEvent.CHANGE:
197 opText = PDEUIMessages.UpdateManager_op_change;
198 break;
199 }
200 return opText;
201 }
202
203 public void setUndoLevelLimit(int limit) {
204 this.undoLevelLimit = limit;
205 }
206
207 public void setIgnoreChanges(boolean ignore) {
208 this.ignoreChanges = ignore;
209 }
210 }
211 |
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