mcs/class/Managed.Windows.Forms/System.Windows.Forms/Timer.cs

   1 // Permission is hereby granted, free of charge, to any person obtaining
   2 // a copy of this software and associated documentation files (the
   3 // "Software"), to deal in the Software without restriction, including
   4 // without limitation the rights to use, copy, modify, merge, publish,
   5 // distribute, sublicense, and/or sell copies of the Software, and to
   6 // permit persons to whom the Software is furnished to do so, subject to
   7 // the following conditions:
   8 //
   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  13 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  16 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2004 Novell, Inc.
  21 //
  22 // Authors:
  23 //      Jackson Harper (jackson@ximian.com)
  24
  25
  26 using System;
  27 using System.Threading;
  28 using System.ComponentModel;
  29
  30 namespace System.Windows.Forms {
  31         [DefaultProperty("Interval")]
  32         [DefaultEvent("Tick")]
  33         [ToolboxItemFilter("System.Windows.Forms", ToolboxItemFilterType.Allow)]
  34         public class Timer : Component {
  35
  36                 private bool enabled;
  37                 private int interval = 100;
  38                 private DateTime expires;
  39                 internal Thread thread;
  40
  41 #if NET_2_0
  42                 object control_tag;
  43 #endif
  44                 internal static readonly int Minimum = 15;
  45
  46                 public Timer ()
  47                 {
  48                         enabled = false;
  49                 }
  50
  51                 public Timer (IContainer container) : this ()
  52                 {
  53                         container.Add (this);
  54                 }
  55
  56                 [DefaultValue (false)]
  57                 public virtual bool Enabled {
  58                         get {
  59                                 return enabled;
  60                         }
  61                         set {
  62                                 if (value != enabled) {
  63                                         enabled = value;
  64                                         if (value) {
  65                                                 // Use AddTicks so we get some rounding
  66                                                 expires = DateTime.UtcNow.AddMilliseconds (interval > Minimum ? interval : Minimum);
  67
  68                                                 thread = Thread.CurrentThread;
  69                                                 XplatUI.SetTimer (this);
  70                                         } else {
  71                                                 XplatUI.KillTimer (this);
  72                                                 thread = null;
  73                                         }
  74                                 }
  75                         }
  76                 }
  77
  78                 [DefaultValue (100)]
  79                 public int Interval {
  80                         get {
  81                                 return interval;
  82                         }
  83                         set {
  84                                 if (interval == value) {
  85                                         return;
  86                                 }
  87
  88                                 interval = value;
  89
  90                                 // Use AddTicks so we get some rounding
  91                                 expires = DateTime.UtcNow.AddMilliseconds (interval > Minimum ? interval : Minimum);
  92
  93                                 if (enabled == true) {
  94                                         XplatUI.KillTimer (this);
  95                                         XplatUI.SetTimer (this);
  96                                 }
  97                         }
  98                 }
  99
 100 #if NET_2_0
 101                 [Localizable(false)]
 102                 [Bindable(true)]
 103                 [TypeConverter(typeof(StringConverter))]
 104                 [DefaultValue(null)]
 105                 [MWFCategory("Data")]
 106                 public object Tag {
 107                         get {
 108                                 return control_tag;
 109                         }
 110
 111                         set {
 112                                 control_tag = value;
 113                         }
 114                 }
 115 #endif
 116
 117                 public void Start ()
 118                 {
 119                         Enabled = true;
 120                 }
 121
 122                 public void Stop ()
 123                 {
 124                         Enabled = false;
 125                 }
 126
 127                 internal DateTime Expires {
 128                         get {
 129                                 return expires;
 130                         }
 131                 }
 132
 133                 public event EventHandler Tick;
 134
 135                 public override string ToString ()
 136                 {
 137                         return base.ToString () + ", Interval: " + Interval;
 138                 }
 139
 140                 internal void Update (DateTime update)
 141                 {
 142                         expires = update.AddMilliseconds (interval > Minimum ? interval : Minimum);
 143                 }
 144
 145                 internal void FireTick ()
 146                 {
 147                         OnTick (EventArgs.Empty);
 148                 }
 149
 150
 151                 protected virtual void OnTick (EventArgs e)
 152                 {
 153                         if (Tick != null)
 154                                 Tick (this, e);
 155                 }
 156
 157                 protected override void Dispose (bool disposing)
 158                 {
 159                         base.Dispose (disposing);
 160                         Enabled = false;
 161                 }
 162
 163                 internal void TickHandler (object sender, EventArgs e)
 164                 {
 165                         OnTick (e);
 166                 }
 167         }
 168 }
 169