我正在使用 QuaggaJs 扫描条形码。对于桌面版扫描仪来说,一切都很好而且很流畅。但是当来到移动版网站时它会被破坏,而且主要是在 iPhone 上。
我在 safari 和 Chrome 中都进行了测试,对于不同的手机,它的行为不同。对于某些手机摄像头挂起,对于某些摄像头根本没有启动。
此外,画布大小未在父 div 中设置。相机正在 DOM 之外。
这就是我所做的。
HTML
<div class="scanner-box">
<div id="scanner-container" class="main_scanner"></div>
</div>
JS
$(document).ready(function(){
if($(".scanner-box").length > 0){
var canvas_width = $(".scanner-box").width();
var canvas_height = $(".scanner-box").height();
if (_scannerIsRunning) {
Quagga.stop();
} else {
startScanner(canvas_width,canvas_height);
}
}
}
var _scannerIsRunning = false;
function startScanner(canvasRatio,canvasHeight) {
Quagga.init({
inputStream: {
name: "Live",
type: "LiveStream",
target: document.querySelector('#scanner-container'),
constraints: {
width: "100%",
height: "100%",
facingMode: "environment"
},
},
decoder: {
readers: [
"ean_reader",
"ean_8_reader"
],
debug: {
showCanvas: true,
showPatches: true,
showFoundPatches: true,
showSkeleton: true,
showLabels: true,
showPatchLabels: true,
showRemainingPatchLabels: true,
boxFromPatches: {
showTransformed: true,
showTransformedBox: true,
showBB: true
}
}
},
},
function (err) {
if (err) {
$("#error").text(err);
return
}
console.log("Initialization finished. Ready to start");
Quagga.start();
_scannerIsRunning = true;
});
Quagga.onProcessed(function (result) {
var drawingCtx = Quagga.canvas.ctx.overlay,
drawingCanvas = Quagga.canvas.dom.overlay;
if (result) {
if (result.boxes) {
drawingCtx.clearRect(0, 0, parseInt(drawingCanvas.getAttribute("width")), parseInt(drawingCanvas.getAttribute("height")));
result.boxes.filter(function (box) {
return box !== result.box;
}).forEach(function (box) {
Quagga.ImageDebug.drawPath(box, { x: 0, y: 1 }, drawingCtx, { color: "green", lineWidth: 2 });
});
}
if (result.box) {
Quagga.ImageDebug.drawPath(result.box, { x: 0, y: 1 }, drawingCtx, { color: "#00F", lineWidth: 2 });
}
if (result.codeResult && result.codeResult.code) {
Quagga.ImageDebug.drawPath(result.line, { x: 'x', y: 'y' }, drawingCtx, { color: 'red', lineWidth: 3 });
}
}
});
Quagga.onDetected(function (result) {
var barcodeResult = $("#result").text(result.codeResult.code);
var barcode = result.codeResult.code;
if(barcode.toString().length < '13'){
}else{
checkBarCode(barcode,canvasRatio,canvasHeight);
if (_scannerIsRunning) {
Quagga.stop();
}
}
console.log("Barcode detected and processed : [" + result.codeResult.code + "]", result);
});
}
CSS
.scanner-box{width:480px;height:320px;background-color:#9a9a9a;position:relative;margin-top:10px;}
#scanner-container{position:relative;height:inherit;}