这期内容当中小编将会给大家带来有关Android 中怎么实现点击生成二维码功能，文章内容丰富且以专业的角度为大家分析和叙述，阅读完这篇文章希望大家可以有所收获。
QRCodeUtil:
package com.example.administrator.zxing;import android.graphics.Bitmap;import android.graphics.Canvas;import com.google.zxing.BarcodeFormat;import com.google.zxing.EncodeHintType;import com.google.zxing.WriterException;import com.google.zxing.common.BitMatrix;import com.google.zxing.qrcode.QRCodeWriter;import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;import java.io.FileOutputStream;import java.io.IOException;import java.util.HashMap;import java.util.Map;public class QRCodeUtil { public static boolean createQRImage(String content, int widthPix, int heightPix, Bitmap logoBm, String filePath) { try { if (content == null || "".equals(content)) { return false; } //配置参数 Map<EncodeHintType, Object> hints = new HashMap<>(); hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); //容错级别 hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); //设置空白边距的宽度// hints.put(EncodeHintType.MARGIN, 2); //default is 4 // 图像数据转换，使用了矩阵转换 BitMatrix bitMatrix = new QRCodeWriter().encode(content, BarcodeFormat.QR_CODE, widthPix, heightPix, hints); int[] pixels = new int[widthPix * heightPix]; // 下面这里按照二维码的算法，逐个生成二维码的图片， // 两个for循环是图片横列扫描的结果 for (int y = 0; y < heightPix; y++) { for (int x = 0; x < widthPix; x++) { if (bitMatrix.get(x, y)) { pixels[y * widthPix + x] = 0xff000000; } else { pixels[y * widthPix + x] = 0xffffffff; } } } // 生成二维码图片的格式，使用ARGB_8888 Bitmap bitmap = Bitmap.createBitmap(widthPix, heightPix, Bitmap.Config.ARGB_8888); bitmap.setPixels(pixels, 0, widthPix, 0, 0, widthPix, heightPix); if (logoBm != null) { bitmap = addLogo(bitmap, logoBm); } //必须使用compress方法将bitmap保存到文件中再进行读取。直接返回的bitmap是没有任何压缩的，内存消耗巨大！ return bitmap != null && bitmap.compress(Bitmap.CompressFormat.JPEG, 100, new FileOutputStream(filePath)); } catch (WriterException | IOException e) { e.printStackTrace(); } return false; } private static Bitmap addLogo(Bitmap src, Bitmap logo) { if (src == null) { return null; } if (logo == null) { return src; } //获取图片的宽高 int srcWidth = src.getWidth(); int srcHeight = src.getHeight(); int logoWidth = logo.getWidth(); int logoHeight = logo.getHeight(); if (srcWidth == 0 || srcHeight == 0) { return null; } if (logoWidth == 0 || logoHeight == 0) { return src; } //logo大小为二维码整体大小的1/5 float scaleFactor = srcWidth * 1.0f / 5 / logoWidth; Bitmap bitmap = Bitmap.createBitmap(srcWidth, srcHeight, Bitmap.Config.ARGB_8888); try { Canvas canvas = new Canvas(bitmap); canvas.drawBitmap(src, 0, 0, null); canvas.scale(scaleFactor, scaleFactor, srcWidth / 2, srcHeight / 2); canvas.drawBitmap(logo, (srcWidth - logoWidth) / 2, (srcHeight - logoHeight) / 2, null); canvas.save(Canvas.ALL_SAVE_FLAG); canvas.restore(); } catch (Exception e) { bitmap = null; e.getStackTrace(); } return bitmap; }}MainActivity:
package com.example.administrator.zxing;import android.content.Context;import android.graphics.BitmapFactory;import android.os.Bundle;import android.os.Environment;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.Button;import android.widget.CheckBox;import android.widget.EditText;import android.widget.ImageView;import java.io.File;public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //内容 final EditText contentET = (EditText) findViewById(R.id.create_qr_content); //显示二维码图片 final ImageView imageView = (ImageView) findViewById(R.id.create_qr_iv); //是否添加Logo final CheckBox addLogoCB = (CheckBox) findViewById(R.id.create_qr_addLogo); Button createQrBtn = (Button) findViewById(R.id.create_qr_btn); createQrBtn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { final String filePath = getFileRoot(MainActivity.this) + File.separator + "qr_" + System.currentTimeMillis() + ".jpg"; //二维码图片较大时，生成图片、保存文件的时间可能较长，因此放在新线程中 new Thread(new Runnable() { @Override public void run() { boolean success = QRCodeUtil.createQRImage(contentET.getText().toString().trim(), 800, 800, addLogoCB.isChecked() ? BitmapFactory.decodeResource(getResources(), R.mipmap.qr_logo) : null, filePath); if (success) { runOnUiThread(new Runnable() { @Override public void run() { imageView.setImageBitmap(BitmapFactory.decodeFile(filePath)); } }); } } }).start(); } }); } //文件存储根目录 private String getFileRoot(Context context) { if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { File external = context.getExternalFilesDir(null); if (external != null) { return external.getAbsolutePath(); } } return context.getFilesDir().getAbsolutePath(); }}布局：
activity_main:
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context="com.example.administrator.zxing.MainActivity"> <EditText android:id="@+id/create_qr_content" android:layout_width="match_parent" android:layout_height="wrap_content" /> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="horizontal"> <Button android:id="@+id/create_qr_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="生成二维码" /> <CheckBox android:id="@+id/create_qr_addLogo" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="添加logo图案" /> </LinearLayout> <ImageView android:id="@+id/create_qr_iv" android:layout_width="match_parent" android:layout_height="wrap_content" /></LinearLayout>上述就是小编为大家分享的Android 中怎么实现点击生成二维码功能了，如果刚好有类似的疑惑，不妨参照上述分析进行理解。如果想知道更多相关知识，欢迎关注编程网行业资讯频道。
