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                 internal bool Busy;
  41                 internal IntPtr window;
  42                 object control_tag;
  43
  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 (value <= 0)
  85                                         throw new ArgumentOutOfRangeException ("Interval", string.Format ("'{0}' is not a valid value for Interval. Interval must be greater than 0.", value));
  86
  87                                 if (interval == value) {
  88                                         return;
  89                                 }
  90
  91                                 interval = value;
  92
  93                                 // Use AddTicks so we get some rounding
  94                                 expires = DateTime.UtcNow.AddMilliseconds (interval > Minimum ? interval : Minimum);
  95
  96                                 if (enabled == true) {
  97                                         XplatUI.KillTimer (this);
  98                                         XplatUI.SetTimer (this);
  99                                 }
 100                         }
 101                 }
 102
 103                 [Localizable(false)]
 104                 [Bindable(true)]
 105                 [TypeConverter(typeof(StringConverter))]
 106                 [DefaultValue(null)]
 107                 [MWFCategory("Data")]
 108                 public object Tag {
 109                         get {
 110                                 return control_tag;
 111                         }
 112
 113                         set {
 114                                 control_tag = value;
 115                         }
 116                 }
 117
 118                 public void Start ()
 119                 {
 120                         Enabled = true;
 121                 }
 122
 123                 public void Stop ()
 124                 {
 125                         Enabled = false;
 126                 }
 127
 128                 internal DateTime Expires {
 129                         get {
 130                                 return expires;
 131                         }
 132                 }
 133
 134                 public event EventHandler Tick;
 135
 136                 public override string ToString ()
 137                 {
 138                         return base.ToString () + ", Interval: " + Interval;
 139                 }
 140
 141                 internal void Update (DateTime update)
 142                 {
 143                         expires = update.AddMilliseconds (interval > Minimum ? interval : Minimum);
 144                 }
 145
 146                 internal void FireTick ()
 147                 {
 148                         OnTick (EventArgs.Empty);
 149                 }
 150
 151
 152                 protected virtual void OnTick (EventArgs e)
 153                 {
 154                         if (Tick != null)
 155                                 Tick (this, e);
 156                 }
 157
 158                 protected override void Dispose (bool disposing)
 159                 {
 160                         base.Dispose (disposing);
 161                         Enabled = false;
 162                 }
 163
 164                 internal void TickHandler (object sender, EventArgs e)
 165                 {
 166                         OnTick (e);
 167                 }
 168         }
 169 }
 170