javascript - Toggle between data in Google Heat Map

Question

Just wondering if there is a easy way to toggle between 2 or more sets of data array variables using the heat map layer with Google Maps?

The classic example of:

var taxiData = [
new google.maps.LatLng(37.782551, -122.445368),
new google.maps.LatLng(37.782745, -122.444586), ...
];

pointArray = new google.maps.MVCArray(taxiData);
heatmap = new google.maps.visualization.HeatmapLayer({
data: pointArray
});
heatmap.setMap(map);

But what if I want to have a vartaxiDataJan, vartaxiDataFeb and toggle between the 2? I want to create a toggle button, and then switch between the data sets, in this case, between 2 months.

I looked at the following: Updating heatmap data, simple google HeatMap

But that only adds a new record to the bottom of the array, whereas I want to replace the complete array

Thanks in advance!

Answer 1

Seems you can only have one HeatMapLayer object at a time. This works for me:

function toggleHeatmap() {
  if (firstData) {
    heatmap.setData(pointArray2);
    firstData=false;
  } else {
    heatmap.setData(pointArray);
    firstData=true;
  }
}

working example

code snippet:

function initialize() {
  var mapOptions = {
    zoom: 10,
    center: new google.maps.LatLng(37.774546, -122.433523),
    mapTypeId: google.maps.MapTypeId.SATELLITE
  };

  map = new google.maps.Map(document.getElementById('map-canvas'),
    mapOptions);

  pointArray = new google.maps.MVCArray(taxiData);
  pointArray2 = new google.maps.MVCArray(taxiData2);

  heatmap = new google.maps.visualization.HeatmapLayer({
    data: pointArray
  })

  heatmap.setMap(map);
  //  heatmap2.setMap(map);
}

function toggleHeatmap() {
  if (firstData) {
    heatmap.setData(pointArray2);
    firstData = false;
  } else {
    heatmap.setData(pointArray);
    firstData = true;
  }
}

function changeGradient() {
  var gradient = [
    'rgba(0, 255, 255, 0)',
    'rgba(0, 255, 255, 1)',
    'rgba(0, 191, 255, 1)',
    'rgba(0, 127, 255, 1)',
    'rgba(0, 63, 255, 1)',
    'rgba(0, 0, 255, 1)',
    'rgba(0, 0, 223, 1)',
    'rgba(0, 0, 191, 1)',
    'rgba(0, 0, 159, 1)',
    'rgba(0, 0, 127, 1)',
    'rgba(63, 0, 91, 1)',
    'rgba(127, 0, 63, 1)',
    'rgba(191, 0, 31, 1)',
    'rgba(255, 0, 0, 1)'
  ]
  heatmap.setOptions({
    gradient: heatmap.get('gradient') ? null : gradient
  });
}

function changeRadius() {
  heatmap.setOptions({
    radius: heatmap.get('radius') ? null : 20
  });
}

function changeOpacity() {
  heatmap.setOptions({
    opacity: heatmap.get('opacity') ? null : 0.2
  });
}

google.maps.event.addDomListener(window, 'load', initialize);

// Adding 500 Data Points
var map = null;
var heatmap = null;
var heatmap2 = null;
var pointArray = null;
var pointArray2 = null;
var firstData = true;
var taxiData = [
  new google.maps.LatLng(37.782551, -122.445368),
  new google.maps.LatLng(37.782745, -122.444586),
  new google.maps.LatLng(37.782842, -122.443688),
  new google.maps.LatLng(37.782919, -122.442815),
  new google.maps.LatLng(37.782992, -122.442112),
  new google.maps.LatLng(37.783100, -122.441461),
  new google.maps.LatLng(37.783206, -122.440829),
  new google.maps.LatLng(37.783273, -122.440324),
  new google.maps.LatLng(37.783316, -122.440023),
  new google.maps.LatLng(37.783357, -122.439794),
  new google.maps.LatLng(37.783371, -122.439687),
  new google.maps.LatLng(37.783368, -122.439666),
  new google.maps.LatLng(37.783383, -122.439594),
  new google.maps.LatLng(37.783508, -122.439525),
  new google.maps.LatLng(37.783842, -122.439591),
  new google.maps.LatLng(37.784147, -122.439668),
  new google.maps.LatLng(37.784206, -122.439686),
  new google.maps.LatLng(37.784386, -122.439790),
  new google.maps.LatLng(37.784701, -122.439902),
  new google.maps.LatLng(37.784965, -122.439938),
  new google.maps.LatLng(37.785010, -122.439947),
  new google.maps.LatLng(37.785360, -122.439952),
  new google.maps.LatLng(37.785715, -122.440030),
  new google.maps.LatLng(37.786117, -122.440119),
  new google.maps.LatLng(37.786564, -122.440209),
  new google.maps.LatLng(37.786905, -122.440270),
  new google.maps.LatLng(37.786956, -122.440279),
  new google.maps.LatLng(37.800224, -122.433520),
  new google.maps.LatLng(37.800155, -122.434101),
  new google.maps.LatLng(37.800160, -122.434430),
  new google.maps.LatLng(37.800378, -122.434527),
  new google.maps.LatLng(37.800738, -122.434598),
  new google.maps.LatLng(37.800938, -122.434650),
  new google.maps.LatLng(37.801024, -122.434889),
  new google.maps.LatLng(37.800955, -122.435392),
  new google.maps.LatLng(37.800886, -122.435959),
  new google.maps.LatLng(37.800811, -122.436275),
  new google.maps.LatLng(37.800788, -122.436299),
  new google.maps.LatLng(37.800719, -122.436302),
  new google.maps.LatLng(37.800702, -122.436298),
  new google.maps.LatLng(37.800661, -122.436273),
  new google.maps.LatLng(37.800395, -122.436172),
  new google.maps.LatLng(37.800228, -122.436116),
  new google.maps.LatLng(37.800169, -122.436130),
  new google.maps.LatLng(37.800066, -122.436167),
  new google.maps.LatLng(37.784345, -122.422922),
  new google.maps.LatLng(37.784389, -122.422926),
  new google.maps.LatLng(37.784437, -122.422924),
  new google.maps.LatLng(37.784746, -122.422818),
  new google.maps.LatLng(37.785436, -122.422959),
  new google.maps.LatLng(37.786120, -122.423112),
  new google.maps.LatLng(37.786433, -122.423029),
  new google.maps.LatLng(37.786631, -122.421213),
  new google.maps.LatLng(37.786660, -122.421033),
  new google.maps.LatLng(37.786801, -122.420141),
  new google.maps.LatLng(37.786823, -122.420034),
  new google.maps.LatLng(37.786831, -122.419916),
  new google.maps.LatLng(37.787034, -122.418208),
  new google.maps.LatLng(37.787056, -122.418034),
  new google.maps.LatLng(37.787169, -122.417145),
  new google.maps.LatLng(37.787217, -122.416715),
  new google.maps.LatLng(37.786144, -122.416403),
  new google.maps.LatLng(37.785292, -122.416257),
  new google.maps.LatLng(37.780666, -122.390374),
  new google.maps.LatLng(37.780501, -122.391281),
  new google.maps.LatLng(37.780148, -122.392052),
  new google.maps.LatLng(37.780173, -122.391148),
  new google.maps.LatLng(37.780693, -122.390592),
  new google.maps.LatLng(37.781261, -122.391142),
  new google.maps.LatLng(37.781808, -122.391730),
  new google.maps.LatLng(37.782340, -122.392341),
  new google.maps.LatLng(37.782812, -122.393022),
  new google.maps.LatLng(37.783300, -122.393672),
  new google.maps.LatLng(37.783809, -122.394275),
  new google.maps.LatLng(37.784246, -122.394979),
  new google.maps.LatLng(37.784791, -122.395958),
  new google.maps.LatLng(37.785675, -122.396746),
  new google.maps.LatLng(37.786262, -122.395780),
  new google.maps.LatLng(37.786776, -122.395093),
  new google.maps.LatLng(37.787282, -122.394426),
  new google.maps.LatLng(37.787783, -122.393767),
  new google.maps.LatLng(37.788343, -122.393184),
  new google.maps.LatLng(37.788895, -122.392506),
  new google.maps.LatLng(37.789371, -122.391701),
  new google.maps.LatLng(37.789722, -122.390952),
  new google.maps.LatLng(37.790315, -122.390305),
  new google.maps.LatLng(37.790738, -122.389616),
  new google.maps.LatLng(37.779448, -122.438702),
  new google.maps.LatLng(37.779023, -122.438585),
  new google.maps.LatLng(37.768244, -122.428138),
  new google.maps.LatLng(37.767942, -122.428581),
  new google.maps.LatLng(37.767482, -122.429094),
  new google.maps.LatLng(37.767031, -122.429606),
  new google.maps.LatLng(37.766732, -122.429986),
  new google.maps.LatLng(37.766680, -122.430058),
  new google.maps.LatLng(37.766633, -122.430109),
  new google.maps.LatLng(37.766580, -122.430211),
  new google.maps.LatLng(37.766367, -122.430594),
  new google.maps.LatLng(37.765910, -122.431137),
  new google.maps.LatLng(37.765353, -122.431806),
  new google.maps.LatLng(37.764962, -122.432298),
  new google.maps.LatLng(37.764868, -122.432486),
  new google.maps.LatLng(37.764518, -122.432913),
  new google.maps.LatLng(37.763435, -122.434173),
  new google.maps.LatLng(37.762847, -122.434953),
  new google.maps.LatLng(37.762291, -122.435935),
  new google.maps.LatLng(37.762224, -122.436074),
  new google.maps.LatLng(37.761957, -122.436892),
  new google.maps.LatLng(37.761652, -122.438886),
  new google.maps.LatLng(37.761284, -122.439955),
  new google.maps.LatLng(37.761210, -122.440068),
  new google.maps.LatLng(37.761064, -122.440720),
  new google.maps.LatLng(37.761040, -122.441411),
  new google.maps.LatLng(37.761048, -122.442324),
  new google.maps.LatLng(37.760851, -122.443118),
  new google.maps.LatLng(37.759977, -122.444591),
  new google.maps.LatLng(37.759913, -122.444698),
  new google.maps.LatLng(37.759623, -122.445065),
  new google.maps.LatLng(37.758902, -122.445158),
  new google.maps.LatLng(37.758428, -122.444570),
  new google.maps.LatLng(37.757687, -122.443340),
  new google.maps.LatLng(37.757583, -122.443240),
  new google.maps.LatLng(37.757019, -122.442787),
  new google.maps.LatLng(37.756603, -122.442322),
  new google.maps.LatLng(37.756380, -122.441602),
  new google.maps.LatLng(37.755790, -122.441382),
  new google.maps.LatLng(37.754493, -122.442133),
  new google.maps.LatLng(37.754361, -122.442206),
  new google.maps.LatLng(37.753719, -122.442650),
  new google.maps.LatLng(37.753096, -122.442915),
  new google.maps.LatLng(37.751617, -122.443211),
  new google.maps.LatLng(37.751496, -122.443246),
  new google.maps.LatLng(37.750733, -122.443428),
  new google.maps.LatLng(37.750126, -122.443536),
  new google.maps.LatLng(37.750103, -122.443784),
  new google.maps.LatLng(37.750390, -122.444010),
  new google.maps.LatLng(37.750448, -122.444013),
  new google.maps.LatLng(37.750536, -122.444040),
  new google.maps.LatLng(37.750493, -122.444141),
  new google.maps.LatLng(37.790859, -122.402808),
  new google.maps.LatLng(37.790864, -122.402768),
  new google.maps.LatLng(37.790995, -122.402539),
  new google.maps.LatLng(37.791148, -122.402172),
  new google.maps.LatLng(37.791385, -122.401312),
  new google.maps.LatLng(37.791405, -122.400776),
  new google.maps.LatLng(37.791288, -122.400528),
  new google.maps.LatLng(37.791113, -122.400441),
  new google.maps.LatLng(37.791027, -122.400395),
  new google.maps.LatLng(37.791094, -122.400311),
  new google.maps.LatLng(37.791211, -122.400183),
  new google.maps.LatLng(37.791060, -122.399334),
  new google.maps.LatLng(37.790538, -122.398718),
  new google.maps.LatLng(37.790095, -122.398086),
  new google.maps.LatLng(37.789644, -122.397360),
  new google.maps.LatLng(37.789254, -122.396844),
  new google.maps.LatLng(37.788855, -122.396397),
  new google.maps.LatLng(37.788483, -122.395963),
  new google.maps.LatLng(37.788015, -122.395365),
  new google.maps.LatLng(37.787558, -122.394735),
  new google.maps.LatLng(37.787472, -122.394323),
  new google.maps.LatLng(37.787630, -122.394025),
  new google.maps.LatLng(37.787767, -122.393987),
  new google.maps.LatLng(37.787486, -122.394452),
  new google.maps.LatLng(37.786977, -122.395043),
  new google.maps.LatLng(37.786583, -122.395552),
  new google.maps.LatLng(37.786540, -122.395610),
  new google.maps.LatLng(37.786516, -122.395659),
  new google.maps.LatLng(37.786378, -122.395707),
  new google.maps.LatLng(37.786044, -122.395362),
  new google.maps.LatLng(37.785598, -122.394715),
  new google.maps.LatLng(37.785321, -122.394361),
  new google.maps.LatLng(37.785207, -122.394236),
  new google.maps.LatLng(37.785751, -122.394062),
  new google.maps.LatLng(37.785996, -122.393881),
  new google.maps.LatLng(37.786092, -122.393830),
  new google.maps.LatLng(37.785998, -122.393899),
  new google.maps.LatLng(37.785114, -122.394365),
  new google.maps.LatLng(37.785022, -122.394441),
  new google.maps.LatLng(37.784823, -122.394635),
  new google.maps.LatLng(37.784719, -122.394629),
  new google.maps.LatLng(37.785069, -122.394176),
  new google.maps.LatLng(37.785500, -122.393650),
  new google.maps.LatLng(37.785770, -122.393291),
  new google.maps.LatLng(37.785839, -122.393159),
  new google.maps.LatLng(37.782651, -122.400628),
  new google.maps.LatLng(37.782616, -122.400599),
  new google.maps.LatLng(37.782702, -122.400470),
  new google.maps.LatLng(37.782915, -122.400192),
  new google.maps.LatLng(37.783137, -122.399887),
  new google.maps.LatLng(37.7