43 lines
1002 B
C#
43 lines
1002 B
C#
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using System;
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using System.Collections;
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namespace Browser
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{
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/// <summary>
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/// Summary description for History.
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/// </summary>
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public class HistoryView
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{
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private Stack backHistory = new Stack();
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private Stack forwardHistory = new Stack();
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private Model model;
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public HistoryView(Model model) {
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this.model = model;
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model.ObjectChangedHandler += new ObjectChangedEventHandler(this.ObjectChanged);
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}
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public void Back() {
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if (backHistory.Count > 1) {
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forwardHistory.Push(backHistory.Pop());
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object o = backHistory.Peek();
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model.ChangeObject(o);
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}
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}
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public void Forward() {
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if (forwardHistory.Count > 0) {
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backHistory.Push(forwardHistory.Pop());
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object o = backHistory.Peek();
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model.ChangeObject(o);
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}
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}
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public void ObjectChanged() {
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object o = model.CurrentObject;
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if (backHistory.Count == 0 || backHistory.Peek() != o) {
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backHistory.Push(o);
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forwardHistory.Clear();
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}
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}
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}
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}
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