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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 | /* Flot plugin for showing a crosshair, thin lines, when the mouse hovers over the plot. crosshair: { mode: null or "x" or "y" or "xy" color: color lineWidth: number } Set the mode to one of "x", "y" or "xy". The "x" mode enables a vertical crosshair that lets you trace the values on the x axis, "y" enables a horizontal crosshair and "xy" enables them both. "color" is the color of the crosshair (default is "rgba(170, 0, 0, 0.80)"), "lineWidth" is the width of the drawn lines (default is 1). The plugin also adds four public methods: - setCrosshair(pos) Set the position of the crosshair. Note that this is cleared if the user moves the mouse. "pos" should be on the form { x: xpos, y: ypos } (or x2 and y2 if you're using the secondary axes), which is coincidentally the same format as what you get from a "plothover" event. If "pos" is null, the crosshair is cleared. - clearCrosshair() Clear the crosshair. - lockCrosshair(pos) Cause the crosshair to lock to the current location, no longer updating if the user moves the mouse. Optionally supply a position (passed on to setCrosshair()) to move it to. Example usage: var myFlot = $.plot( $("#graph"), ..., { crosshair: { mode: "x" } } }; $("#graph").bind("plothover", function (evt, position, item) { if (item) { // Lock the crosshair to the data point being hovered myFlot.lockCrosshair({ x: item.datapoint[0], y: item.datapoint[1] }); } else { // Return normal crosshair operation myFlot.unlockCrosshair(); } }); - unlockCrosshair() Free the crosshair to move again after locking it. */ (function ($) { var options = { crosshair: { mode: null, // one of null, "x", "y" or "xy", color: "rgba(170, 0, 0, 0.80)", lineWidth: 1 } }; function init(plot) { // position of crosshair in pixels var crosshair = { x: -1, y: -1, locked: false }; plot.setCrosshair = function setCrosshair(pos) { if (!pos) crosshair.x = -1; else { var axes = plot.getAxes(); crosshair.x = Math.max(0, Math.min(pos.x != null ? axes.xaxis.p2c(pos.x) : axes.x2axis.p2c(pos.x2), plot.width())); crosshair.y = Math.max(0, Math.min(pos.y != null ? axes.yaxis.p2c(pos.y) : axes.y2axis.p2c(pos.y2), plot.height())); } plot.triggerRedrawOverlay(); }; plot.clearCrosshair = plot.setCrosshair; // passes null for pos plot.lockCrosshair = function lockCrosshair(pos) { if (pos) plot.setCrosshair(pos); crosshair.locked = true; } plot.unlockCrosshair = function unlockCrosshair() { crosshair.locked = false; } plot.hooks.bindEvents.push(function (plot, eventHolder) { if (!plot.getOptions().crosshair.mode) return; eventHolder.mouseout(function () { if (crosshair.x != -1) { crosshair.x = -1; plot.triggerRedrawOverlay(); } }); eventHolder.mousemove(function (e) { if (plot.getSelection && plot.getSelection()) { crosshair.x = -1; // hide the crosshair while selecting return; } if (crosshair.locked) return; var offset = plot.offset(); crosshair.x = Math.max(0, Math.min(e.pageX - offset.left, plot.width())); crosshair.y = Math.max(0, Math.min(e.pageY - offset.top, plot.height())); plot.triggerRedrawOverlay(); }); }); plot.hooks.drawOverlay.push(function (plot, ctx) { var c = plot.getOptions().crosshair; if (!c.mode) return; var plotOffset = plot.getPlotOffset(); ctx.save(); ctx.translate(plotOffset.left, plotOffset.top); if (crosshair.x != -1) { ctx.strokeStyle = c.color; ctx.lineWidth = c.lineWidth; ctx.lineJoin = "round"; ctx.beginPath(); if (c.mode.indexOf("x") != -1) { ctx.moveTo(crosshair.x, 0); ctx.lineTo(crosshair.x, plot.height()); } if (c.mode.indexOf("y") != -1) { ctx.moveTo(0, crosshair.y); ctx.lineTo(plot.width(), crosshair.y); } ctx.stroke(); } ctx.restore(); }); } $.plot.plugins.push({ init: init, options: options, name: 'crosshair', version: '1.0' }); })(jQuery); |