extlib/leaflet/src/handler/ShiftDragZoom.js

   1 /*
   2  * L.Handler.ShiftDragZoom is used internally by L.Map to add shift-drag zoom (zoom to a selected bounding box).
   3  */
   4
   5 L.Handler.ShiftDragZoom = L.Handler.extend({
   6         initialize: function(map) {
   7                 this._map = map;
   8                 this._container = map._container;
   9                 this._pane = map._panes.overlayPane;
  10         },
  11
  12         enable: function() {
  13                 if (this._enabled) { return; }
  14
  15                 L.DomEvent.addListener(this._container, 'mousedown', this._onMouseDown, this);
  16
  17                 this._enabled = true;
  18         },
  19
  20         disable: function() {
  21                 if (!this._enabled) { return; }
  22
  23                 L.DomEvent.removeListener(this._container, 'mousedown', this._onMouseDown);
  24
  25                 this._enabled = false;
  26         },
  27
  28         _onMouseDown: function(e) {
  29                 if (!e.shiftKey || ((e.which != 1) && (e.button != 1))) { return false; }
  30
  31                 L.DomUtil.disableTextSelection();
  32
  33                 this._startLayerPoint = this._map.mouseEventToLayerPoint(e);
  34
  35                 this._box = L.DomUtil.create('div', 'leaflet-zoom-box', this._pane);
  36                 L.DomUtil.setPosition(this._box, this._startLayerPoint);
  37
  38                 //TODO move cursor to styles
  39                 this._container.style.cursor = 'crosshair';
  40
  41                 L.DomEvent.addListener(document, 'mousemove', this._onMouseMove, this);
  42                 L.DomEvent.addListener(document, 'mouseup', this._onMouseUp, this);
  43
  44                 L.DomEvent.preventDefault(e);
  45         },
  46
  47         _onMouseMove: function(e) {
  48                 var layerPoint = this._map.mouseEventToLayerPoint(e),
  49                         dx = layerPoint.x - this._startLayerPoint.x,
  50                         dy = layerPoint.y - this._startLayerPoint.y;
  51
  52                 var newX = Math.min(layerPoint.x, this._startLayerPoint.x),
  53                         newY = Math.min(layerPoint.y, this._startLayerPoint.y),
  54                         newPos = new L.Point(newX, newY);
  55
  56                 L.DomUtil.setPosition(this._box, newPos);
  57
  58                 this._box.style.width = (Math.abs(dx) - 4) + 'px';
  59                 this._box.style.height = (Math.abs(dy) - 4) + 'px';
  60         },
  61
  62         _onMouseUp: function(e) {
  63                 this._pane.removeChild(this._box);
  64                 this._container.style.cursor = '';
  65
  66                 L.DomUtil.enableTextSelection();
  67
  68                 L.DomEvent.removeListener(document, 'mousemove', this._onMouseMove);
  69                 L.DomEvent.removeListener(document, 'mouseup', this._onMouseUp);
  70
  71                 var layerPoint = this._map.mouseEventToLayerPoint(e);
  72
  73                 var bounds = new L.LatLngBounds(
  74                                 this._map.layerPointToLatLng(this._startLayerPoint),
  75                                 this._map.layerPointToLatLng(layerPoint));
  76
  77                 this._map.fitBounds(bounds);
  78         }
  79 });