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1
11 package org.eclipse.core.internal.databinding.observable.masterdetail;
12
13 import java.util.HashSet  ;
14 import java.util.Set ;
15
16 import org.eclipse.core.databinding.observable.Diffs;
17 import org.eclipse.core.databinding.observable.IObserving;
18 import org.eclipse.core.databinding.observable.masterdetail.IObservableFactory;
19 import org.eclipse.core.databinding.observable.set.IObservableSet;
20 import org.eclipse.core.databinding.observable.set.ISetChangeListener;
21 import org.eclipse.core.databinding.observable.set.ObservableSet;
22 import org.eclipse.core.databinding.observable.set.SetChangeEvent;
23 import org.eclipse.core.databinding.observable.value.IObservableValue;
24 import org.eclipse.core.databinding.observable.value.IValueChangeListener;
25 import org.eclipse.core.databinding.observable.value.ValueChangeEvent;
26 import org.eclipse.core.runtime.Assert;
27
28
32 public class DetailObservableSet extends ObservableSet implements IObserving {
33
34 private boolean updating = false;
35
36 private ISetChangeListener innerChangeListener = new ISetChangeListener() {
37 public void handleSetChange(SetChangeEvent event) {
38 if (!updating) {
39 fireSetChange(event.diff);
40 }
41 }
42 };
43
44 private Object currentOuterValue;
45
46 private IObservableSet innerObservableSet;
47
48 private IObservableValue outerObservableValue;
49
50 private IObservableFactory factory;
51
52
57 public DetailObservableSet(IObservableFactory factory,
58 IObservableValue outerObservableValue, Object detailType) {
59 super(outerObservableValue.getRealm(), new HashSet (), detailType);
60 this.factory = factory;
61 this.outerObservableValue = outerObservableValue;
62 updateInnerObservableValue(outerObservableValue);
63
64 outerObservableValue.addValueChangeListener(outerChangeListener);
65 }
66
67 IValueChangeListener outerChangeListener = new IValueChangeListener() {
68 public void handleValueChange(ValueChangeEvent event) {
69 Set oldSet = new HashSet (wrappedSet);
70 updateInnerObservableValue(outerObservableValue);
71 fireSetChange(Diffs.computeSetDiff(oldSet, wrappedSet));
72 }
73 };
74
75 private void updateInnerObservableValue(
76 IObservableValue outerObservableValue) {
77 currentOuterValue = outerObservableValue.getValue();
78 if (innerObservableSet != null) {
79 innerObservableSet.removeSetChangeListener(innerChangeListener);
80 innerObservableSet.dispose();
81 }
82 if (currentOuterValue == null) {
83 innerObservableSet = null;
84 wrappedSet = new HashSet ();
85 } else {
86 this.innerObservableSet = (IObservableSet) factory
87 .createObservable(currentOuterValue);
88 wrappedSet = innerObservableSet;
89
90 if (elementType != null) {
91 Object innerValueType = innerObservableSet.getElementType();
92
93 Assert.isTrue(elementType.equals(innerValueType),
94 "Cannot change value type in a nested observable set"); }
96
97 innerObservableSet.addSetChangeListener(innerChangeListener);
98 }
99 }
100
101 public void dispose() {
102 super.dispose();
103
104 if (outerObservableValue != null) {
105 outerObservableValue.removeValueChangeListener(outerChangeListener);
106 outerObservableValue.dispose();
107 }
108 if (innerObservableSet != null) {
109 innerObservableSet.removeSetChangeListener(innerChangeListener);
110 innerObservableSet.dispose();
111 }
112 currentOuterValue = null;
113 factory = null;
114 innerObservableSet = null;
115 innerChangeListener = null;
116 }
117
118 public Object getObserved() {
119 if (innerObservableSet instanceof IObserving) {
120 return ((IObserving)innerObservableSet).getObserved();
121 }
122 return null;
123 }
124
125 }
126 |
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