dygraphs
Version:
dygraphs is a fast, flexible open source JavaScript charting library.
197 lines (185 loc) • 7.54 kB
JavaScript
/*global Gallery,Dygraph,data */
//galleryActive=true
Gallery.register(
'drawing',
{
name: 'Time Series Drawing Demo',
title: 'Time Series Drawing Demo',
setup: function(parent) {
parent.innerHTML = [
"<div id='toolbar'>",
"<div id='tool_zoom'></div>",
"<div id='tool_pencil'></div>",
"<div id='tool_eraser'></div>",
"</div>",
"<div id='draw_div' style='width: 600px; height: 300px;'></div>"].join("\n");
},
run: function() {
var change_tool; // defined below.
var zoom = document.getElementById('tool_zoom');
zoom.onclick = function() { change_tool(zoom); };
var pencil = document.getElementById('tool_pencil');
pencil.onclick = function() { change_tool(pencil); };
var eraser = document.getElementById('tool_eraser');
eraser.onclick = function() { change_tool(eraser); };
var start_date = new Date("2002/12/29").getTime();
var end_date = new Date().getTime();
var data = [];
for (var d = start_date; d < end_date; d += 604800 * 1000) {
var millis = d + 2 * 3600 * 1000;
data.push( [ new Date(Dygraph.dateString_(millis)), 50 ]);
}
var isDrawing = false;
var lastDrawRow = null, lastDrawValue = null;
var tool = 'pencil';
var valueRange = [0, 100];
function setPoint(event, g, context) {
var graphPos = Dygraph.findPos(g.graphDiv);
var canvasx = Dygraph.pageX(event) - graphPos.x;
var canvasy = Dygraph.pageY(event) - graphPos.y;
var xy = g.toDataCoords(canvasx, canvasy);
var x = xy[0], value = xy[1];
var rows = g.numRows();
var closest_row = -1;
var smallest_diff = -1;
// TODO(danvk): binary search
for (var row = 0; row < rows; row++) {
var date = g.getValue(row, 0); // millis
var diff = Math.abs(date - x);
if (smallest_diff < 0 || diff < smallest_diff) {
smallest_diff = diff;
closest_row = row;
}
}
if (closest_row != -1) {
if (lastDrawRow === null) {
lastDrawRow = closest_row;
lastDrawValue = value;
}
var coeff = (value - lastDrawValue) / (closest_row - lastDrawRow);
if (closest_row == lastDrawRow) coeff = 0.0;
var minRow = Math.min(lastDrawRow, closest_row);
var maxRow = Math.max(lastDrawRow, closest_row);
for (var row = minRow; row <= maxRow; row++) {
if (tool == 'pencil') {
var val = lastDrawValue + coeff * (row - lastDrawRow);
val = Math.max(valueRange[0], Math.min(val, valueRange[1]));
data[row][1] = val;
if (val === null || value === undefined || isNaN(val)) {
console.log(val);
}
} else if (tool == 'eraser') {
data[row][1] = null;
}
}
lastDrawRow = closest_row;
lastDrawValue = value;
g.updateOptions({ file: data });
g.setSelection(closest_row); // prevents the dot from being finnicky.
}
}
function finishDraw() {
isDrawing = false;
lastDrawRow = null;
lastDrawValue = null;
}
change_tool = function(tool_div) {
var ids = ['tool_zoom', 'tool_pencil', 'tool_eraser'];
for (var i = 0; i < ids.length; i++) {
var div = document.getElementById(ids[i]);
if (div == tool_div) {
div.style.backgroundPosition = -(i * 32) + 'px -32px';
} else {
div.style.backgroundPosition = -(i * 32) + 'px 0px';
}
}
tool = tool_div.id.replace('tool_', '');
var dg_div = document.getElementById("draw_div");
if (tool == 'pencil') {
dg_div.style.cursor = 'url(../common/cursor-pencil.png) 2 30, auto';
} else if (tool == 'eraser') {
dg_div.style.cursor = 'url(../common/cursor-eraser.png) 10 30, auto';
} else if (tool == 'zoom') {
dg_div.style.cursor = 'crosshair';
}
};
change_tool(document.getElementById("tool_pencil"));
new Dygraph(document.getElementById("draw_div"), data,
{
valueRange: valueRange,
labels: [ 'Date', 'Value' ],
interactionModel: {
// the next line is required when using the
// defaultInteractionModel mousedown function.
willDestroyContextMyself: true,
mousedown: function (event, g, context) {
if (tool == 'zoom') {
Dygraph.defaultInteractionModel.mousedown(event, g, context);
} else {
// prevents mouse drags from selecting page text.
if (event.preventDefault) {
event.preventDefault(); // Firefox, Chrome, etc.
} else {
event.returnValue = false; // IE
event.cancelBubble = true;
}
isDrawing = true;
setPoint(event, g, context);
}
},
mousemove: function (event, g, context) {
// note that the defaultInteractionModel dynamically binds
// its own mousemove event inside the mousedown handler
if (tool != 'zoom') {
if (!isDrawing) return;
setPoint(event, g, context);
}
},
mouseup: function(event, g, context) {
// note that the defaultInteractionModel dynamically binds
// its own mouseup event inside the mousedown handler
if (tool != 'zoom') {
finishDraw();
}
},
mouseout: function(event, g, context) {
// note that the defaultInteractionModel does not use
// the mouseout event, instead it detects when the mouse
// is outside the chart using a dynamically bound
// mousemove event
},
dblclick: function(event, g, context) {
Dygraph.defaultInteractionModel.dblclick(event, g, context);
},
mousewheel: function(event, g, context) {
var normal = event.detail ? event.detail * -1 : event.wheelDelta / 40;
var percentage = normal / 50;
var axis = g.xAxisRange();
var xOffset = g.toDomCoords(axis[0], null)[0];
var x = event.offsetX - xOffset;
var w = g.toDomCoords(axis[1], null)[0] - xOffset;
var xPct = w === 0 ? 0 : (x / w);
var delta = axis[1] - axis[0];
var increment = delta * percentage;
var foo = [increment * xPct, increment * (1 - xPct)];
var dateWindow = [ axis[0] + foo[0], axis[1] - foo[1] ];
g.updateOptions({
dateWindow: dateWindow
});
event.preventDefault();
}
},
strokeWidth: 1.5,
gridLineColor: 'rgb(196, 196, 196)',
axes: {
x: {
drawAxis: false
},
y: {
drawGrid: false
}
}
});
window.onmouseup = finishDraw;
}
});