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| 58d006 | 1 | /* Flot plugin for showing crosshairs when the mouse hovers over the plot. |
| A | 2 | |
| 3 | Copyright (c) 2007-2013 IOLA and Ole Laursen. | |
| 4 | Licensed under the MIT license. | |
| 5 | ||
| 6 | The plugin supports these options: | |
| 7 | ||
| 8 | crosshair: { | |
| 9 | mode: null or "x" or "y" or "xy" | |
| 10 | color: color | |
| 11 | lineWidth: number | |
| 12 | } | |
| 13 | ||
| 14 | Set the mode to one of "x", "y" or "xy". The "x" mode enables a vertical | |
| 15 | crosshair that lets you trace the values on the x axis, "y" enables a | |
| 16 | horizontal crosshair and "xy" enables them both. "color" is the color of the | |
| 17 | crosshair (default is "rgba(170, 0, 0, 0.80)"), "lineWidth" is the width of | |
| 18 | the drawn lines (default is 1). | |
| 19 | ||
| 20 | The plugin also adds four public methods: | |
| 21 | ||
| 22 | - setCrosshair( pos ) | |
| 23 | ||
| 24 | Set the position of the crosshair. Note that this is cleared if the user | |
| 25 | moves the mouse. "pos" is in coordinates of the plot and should be on the | |
| 26 | form { x: xpos, y: ypos } (you can use x2/x3/... if you're using multiple | |
| 27 | axes), which is coincidentally the same format as what you get from a | |
| 28 | "plothover" event. If "pos" is null, the crosshair is cleared. | |
| 29 | ||
| 30 | - clearCrosshair() | |
| 31 | ||
| 32 | Clear the crosshair. | |
| 33 | ||
| 34 | - lockCrosshair(pos) | |
| 35 | ||
| 36 | Cause the crosshair to lock to the current location, no longer updating if | |
| 37 | the user moves the mouse. Optionally supply a position (passed on to | |
| 38 | setCrosshair()) to move it to. | |
| 39 | ||
| 40 | Example usage: | |
| 41 | ||
| 42 | var myFlot = $.plot( $("#graph"), ..., { crosshair: { mode: "x" } } }; | |
| 43 | $("#graph").bind( "plothover", function ( evt, position, item ) { | |
| 44 | if ( item ) { | |
| 45 | // Lock the crosshair to the data point being hovered | |
| 46 | myFlot.lockCrosshair({ | |
| 47 | x: item.datapoint[ 0 ], | |
| 48 | y: item.datapoint[ 1 ] | |
| 49 | }); | |
| 50 | } else { | |
| 51 | // Return normal crosshair operation | |
| 52 | myFlot.unlockCrosshair(); | |
| 53 | } | |
| 54 | }); | |
| 55 | ||
| 56 | - unlockCrosshair() | |
| 57 | ||
| 58 | Free the crosshair to move again after locking it. | |
| 59 | */ | |
| 60 | ||
| 61 | (function ($) { | |
| 62 | var options = { | |
| 63 | crosshair: { | |
| 64 | mode: null, // one of null, "x", "y" or "xy", | |
| 65 | color: "rgba(170, 0, 0, 0.80)", | |
| 66 | lineWidth: 1 | |
| 67 | } | |
| 68 | }; | |
| 69 | ||
| 70 | function init(plot) { | |
| 71 | // position of crosshair in pixels | |
| 72 | var crosshair = { x: -1, y: -1, locked: false }; | |
| 73 | ||
| 74 | plot.setCrosshair = function setCrosshair(pos) { | |
| 75 | if (!pos) | |
| 76 | crosshair.x = -1; | |
| 77 | else { | |
| 78 | var o = plot.p2c(pos); | |
| 79 | crosshair.x = Math.max(0, Math.min(o.left, plot.width())); | |
| 80 | crosshair.y = Math.max(0, Math.min(o.top, plot.height())); | |
| 81 | } | |
| 82 | ||
| 83 | plot.triggerRedrawOverlay(); | |
| 84 | }; | |
| 85 | ||
| 86 | plot.clearCrosshair = plot.setCrosshair; // passes null for pos | |
| 87 | ||
| 88 | plot.lockCrosshair = function lockCrosshair(pos) { | |
| 89 | if (pos) | |
| 90 | plot.setCrosshair(pos); | |
| 91 | crosshair.locked = true; | |
| 92 | }; | |
| 93 | ||
| 94 | plot.unlockCrosshair = function unlockCrosshair() { | |
| 95 | crosshair.locked = false; | |
| 96 | }; | |
| 97 | ||
| 98 | function onMouseOut(e) { | |
| 99 | if (crosshair.locked) | |
| 100 | return; | |
| 101 | ||
| 102 | if (crosshair.x != -1) { | |
| 103 | crosshair.x = -1; | |
| 104 | plot.triggerRedrawOverlay(); | |
| 105 | } | |
| 106 | } | |
| 107 | ||
| 108 | function onMouseMove(e) { | |
| 109 | if (crosshair.locked) | |
| 110 | return; | |
| 111 | ||
| 112 | if (plot.getSelection && plot.getSelection()) { | |
| 113 | crosshair.x = -1; // hide the crosshair while selecting | |
| 114 | return; | |
| 115 | } | |
| 116 | ||
| 117 | var offset = plot.offset(); | |
| 118 | crosshair.x = Math.max(0, Math.min(e.pageX - offset.left, plot.width())); | |
| 119 | crosshair.y = Math.max(0, Math.min(e.pageY - offset.top, plot.height())); | |
| 120 | plot.triggerRedrawOverlay(); | |
| 121 | } | |
| 122 | ||
| 123 | plot.hooks.bindEvents.push(function (plot, eventHolder) { | |
| 124 | if (!plot.getOptions().crosshair.mode) | |
| 125 | return; | |
| 126 | ||
| 127 | eventHolder.mouseout(onMouseOut); | |
| 128 | eventHolder.mousemove(onMouseMove); | |
| 129 | }); | |
| 130 | ||
| 131 | plot.hooks.drawOverlay.push(function (plot, ctx) { | |
| 132 | var c = plot.getOptions().crosshair; | |
| 133 | if (!c.mode) | |
| 134 | return; | |
| 135 | ||
| 136 | var plotOffset = plot.getPlotOffset(); | |
| 137 | ||
| 138 | ctx.save(); | |
| 139 | ctx.translate(plotOffset.left, plotOffset.top); | |
| 140 | ||
| 141 | if (crosshair.x != -1) { | |
| 142 | var adj = plot.getOptions().crosshair.lineWidth % 2 === 0 ? 0 : 0.5; | |
| 143 | ||
| 144 | ctx.strokeStyle = c.color; | |
| 145 | ctx.lineWidth = c.lineWidth; | |
| 146 | ctx.lineJoin = "round"; | |
| 147 | ||
| 148 | ctx.beginPath(); | |
| 149 | if (c.mode.indexOf("x") != -1) { | |
| 150 | var drawX = Math.round(crosshair.x) + adj; | |
| 151 | ctx.moveTo(drawX, 0); | |
| 152 | ctx.lineTo(drawX, plot.height()); | |
| 153 | } | |
| 154 | if (c.mode.indexOf("y") != -1) { | |
| 155 | var drawY = Math.round(crosshair.y) + adj; | |
| 156 | ctx.moveTo(0, drawY); | |
| 157 | ctx.lineTo(plot.width(), drawY); | |
| 158 | } | |
| 159 | ctx.stroke(); | |
| 160 | } | |
| 161 | ctx.restore(); | |
| 162 | }); | |
| 163 | ||
| 164 | plot.hooks.shutdown.push(function (plot, eventHolder) { | |
| 165 | eventHolder.unbind("mouseout", onMouseOut); | |
| 166 | eventHolder.unbind("mousemove", onMouseMove); | |
| 167 | }); | |
| 168 | } | |
| 169 | ||
| 170 | $.plot.plugins.push({ | |
| 171 | init: init, | |
| 172 | options: options, | |
| 173 | name: 'crosshair', | |
| 174 | version: '1.0' | |
| 175 | }); | |
| 176 | })(jQuery); | |
