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POHow to resolve the canvas error in QR Code generation
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  1. POHow to resolve the canvas error in QR Code generation
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    copied!<p>I am trying to execute the QR Code tutorial according to this website <a href="http://www.onbarcode.com/products/android_barcode/barcodes/qrcode.html" rel="nofollow">http://www.onbarcode.com/products/android_barcode/barcodes/qrcode.html</a>, where only one error shoots up "canvas cannot be resolved to a variable</p> <p>Here is the Java code</p> <pre><code> package com.qrcode; import com.onbarcode.barcode.android.AndroidColor; import com.onbarcode.barcode.android.IBarcode; import com.onbarcode.barcode.android.QRCode; import android.app.Activity; import android.graphics.Canvas; import android.graphics.RectF; import android.os.Bundle; public class QrcodeActivity extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); QRCode barcode = new QRCode(); /* QRCode Valid data char set: numeric data (digits 0 - 9); alphanumeric data (digits 0 - 9; upper case letters A -Z; nine other characters: space, $ % * + - . / : ); byte data (default: ISO/IEC 8859-1); Kanji characters */ barcode.setData("http://www.onbarcode.com"); barcode.setDataMode(QRCode.M_AUTO); barcode.setVersion(10); barcode.setEcl(QRCode.ECL_M); // if you want to encode GS1 compatible QR Code, you need set FNC1 mode to IBarcode.FNC1_ENABLE barcode.setFnc1Mode(IBarcode.FNC1_NONE); // Set the processTilde property to true, if you want use the tilde character "~" to // specify special characters in the input data. Default is false. // 1-byte character: ~ddd (character value from 0 ~ 255) // ASCII (with EXT): from ~000 to ~255 // 2-byte character: ~6ddddd (character value from 0 ~ 65535) // Unicode: from ~600000 to ~665535 // ECI: from ~7000000 to ~7999999 // SJIS: from ~9ddddd (Shift JIS 0x8140 ~ 0x9FFC and 0xE040 ~ 0xEBBF) barcode.setProcessTilde(false); // unit of measure for X, Y, LeftMargin, RightMargin, TopMargin, BottomMargin barcode.setUom(IBarcode.UOM_PIXEL); // barcode module width in pixel barcode.setX(3f); barcode.setLeftMargin(15f); barcode.setRightMargin(15f); barcode.setTopMargin(15f); barcode.setBottomMargin(15f); // barcode image resolution in dpi barcode.setResolution(72); // barcode bar color and background color in Android device barcode.setForeColor(AndroidColor.black); barcode.setBackColor(AndroidColor.white); /* specify your barcode drawing area */ RectF bounds = new RectF(30, 30, 0, 0); ************************ERROR Shoots up in the below line stating "canvas cannot be resolved into a variable*************** barcode.drawBarcode(canvas, bounds); } } </code></pre> <p>Here is my main.xml</p> <pre><code> &lt;?xml version="1.0" encoding="utf-8"?&gt; &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" &gt; &lt;/LinearLayout&gt; </code></pre> <p>Am a naive in qr generation, so please help me with the rest of the code friends</p>
 

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