KancolleSniffer/View/ListScroller.cs

   1 // Copyright (C) 2019 Kazuhiro Fujieda <fujieda@users.osdn.me>\r
   2 //\r
   3 // Licensed under the Apache License, Version 2.0 (the "License");\r
   4 // you may not use this file except in compliance with the License.\r
   5 // You may obtain a copy of the License at\r
   6 //\r
   7 //    http://www.apache.org/licenses/LICENSE-2.0\r
   8 //\r
   9 // Unless required by applicable law or agreed to in writing, software\r
  10 // distributed under the License is distributed on an "AS IS" BASIS,\r
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  12 // See the License for the specific language governing permissions and\r
  13 // limitations under the License.\r
  14 \r
  15 using System;\r
  16 using System.Drawing;\r
  17 using System.Windows.Forms;\r
  18 \r
  19 namespace KancolleSniffer.View\r
  20 {\r
  21     public class ListScroller\r
  22     {\r
  23         private readonly Panel _panel;\r
  24 \r
  25         public int Padding { get; set; }\r
  26 \r
  27         public int Position { get; set; }\r
  28 \r
  29         public int Lines { get; set; }\r
  30 \r
  31         public int DataCount { get; set; }\r
  32 \r
  33         public event Action Update;\r
  34 \r
  35         public ListScroller(Panel panel, Label[] topLabels, Label[] bottomLabels)\r
  36         {\r
  37             _panel = panel;\r
  38             panel.Paint += (obj, ev) => DrawMark();\r
  39             SetTopEventHandler(topLabels);\r
  40             SetBottomEventHandler(bottomLabels);\r
  41         }\r
  42 \r
  43         public void SetTopEventHandler(Label[] top)\r
  44         {\r
  45             foreach (var label in top)\r
  46             {\r
  47                 label.MouseEnter += TopLineOnMouseEnter;\r
  48                 label.MouseLeave += TopLineOnMouseLeave;\r
  49             }\r
  50             _topScrollRepeatTimer.Tick += TopLineOnMouseEnter;\r
  51         }\r
  52 \r
  53         public void SetBottomEventHandler(Label[] bottom)\r
  54         {\r
  55             foreach (var label in bottom)\r
  56             {\r
  57                 label.MouseEnter += BottomLineOnMouseEnter;\r
  58                 label.MouseLeave += BottomLineOnMouseLeave;\r
  59             }\r
  60             _bottomScrollRepeatTimer.Tick += BottomLineOnMouseEnter;\r
  61         }\r
  62 \r
  63         private readonly Timer _topScrollRepeatTimer = new Timer {Interval = 100};\r
  64         private readonly Timer _bottomScrollRepeatTimer = new Timer {Interval = 100};\r
  65 \r
  66         private void TopLineOnMouseEnter(object sender, EventArgs e)\r
  67         {\r
  68             if (Position == 0)\r
  69                 return;\r
  70             Position--;\r
  71             Update?.Invoke();\r
  72             _topScrollRepeatTimer.Start();\r
  73         }\r
  74 \r
  75         private void TopLineOnMouseLeave(object sender, EventArgs e)\r
  76         {\r
  77             _topScrollRepeatTimer.Stop();\r
  78         }\r
  79 \r
  80         private void BottomLineOnMouseEnter(object sender, EventArgs e)\r
  81         {\r
  82             if (Position + Lines >= DataCount)\r
  83                 return;\r
  84             Position++;\r
  85             Update?.Invoke();\r
  86             _bottomScrollRepeatTimer.Start();\r
  87         }\r
  88 \r
  89         private void BottomLineOnMouseLeave(object sender, EventArgs e)\r
  90         {\r
  91             _bottomScrollRepeatTimer.Stop();\r
  92         }\r
  93 \r
  94         public void DrawMark()\r
  95         {\r
  96             using (var g = _panel.CreateGraphics())\r
  97             {\r
  98                 var topBrush = Position > 0 ? Brushes.Black : new SolidBrush(_panel.BackColor);\r
  99                 g.FillPolygon(topBrush,\r
 100                     new[]\r
 101                     {\r
 102                         new PointF(_panel.Width * 0.45f, Padding), new PointF(_panel.Width * 0.55f, Padding),\r
 103                         new PointF(_panel.Width * 0.5f, 0), new PointF(_panel.Width * 0.45f, Padding)\r
 104                     });\r
 105                 var bottomBrush = Position + Lines < DataCount\r
 106                     ? Brushes.Black\r
 107                     : new SolidBrush(_panel.BackColor);\r
 108                 g.FillPolygon(bottomBrush,\r
 109                     new[]\r
 110                     {\r
 111                         new PointF(_panel.Width * 0.45f, _panel.Height - Padding - 2),\r
 112                         new PointF(_panel.Width * 0.55f, _panel.Height - Padding - 2),\r
 113                         new PointF(_panel.Width * 0.5f, _panel.Height - 2),\r
 114                         new PointF(_panel.Width * 0.45f, _panel.Height - Padding - 2)\r
 115                     });\r
 116             }\r
 117         }\r
 118     }\r
 119 }