菜鸟的自己今天又回顾了一下二维码的实现

这是老大给我的第二个任务，让我研究一下二维码的功能，菜鸟的自己半天实现了扫描和生成二维码的功能，记下来吧。 首先还是在gitHub小伙伴的帮助下完成的，非常感谢，希望gitHub多出点这样的精华  1.去gitHub上下载库，链接（https://github.com/XuDaojie/QRCode-Android）  2.将该demo中的qrcodelib作为module导入到你的项目，修改你的build.gradle配置，分别添加如下代码：

compile 'com.github.XuDaojie:QRCode-Android:v0.4.2'

和marven；

repositories {
maven { url "http://repo1.maven.org/maven2" }
maven { url 'https://jitpack.io' }
}

有了这些你的准备工作就完事了,让你的工程依赖你所导入的jar包

接下来开始准备代码部分：

<LinearLayout 

xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="10dp"
android:paddingLeft="2dp"
android:paddingRight="2dp"
android:paddingTop="2dp"
android:gravity="center"
android:orientation="vertical"
tools:context="com.dmdfchina.view.ZxingActivity">

<Button
android:id="@+id/btn_switch"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:text="扫描" />
<TextView
android:id="@+id/tv_result"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:textColor="@android:color/holo_blue_bright"
android:text="ss"
android:textSize="18sp" />

<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="请输入你想输入的内容"
android:id="@+id/btn_hint1"
android:layout_alignTop="@+id/btn_switch"
android:layout_centerHorizontal="true" />

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="生成二维码"
android:id="@+id/btn_hint2"
android:layout_alignTop="@+id/btn_hint1"
android:layout_alignParentEnd="true" />

<ImageView
android:id="@+id/img_shouw"
android:layout_width="wrap_content"
android:layout_gravity="center"
android:background="@mipmap/ic_launcher"
android:layout_height="wrap_content"/>

</LinearLayout>

核心代码部分：

public class ZxingActivity extends AppCompatActivity implements View.OnClickListener {private static final int REQUEST_OK=1001;private Button scan, generate;private EditText content;private ImageView mShowImg;private TextView mQRCodeResult;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_zxing);initViewById();}private void initViewById() {scan = (Button) findViewById(R.id.btn_switch);content = (EditText) findViewById(R.id.btn_hint1);generate = (Button) findViewById(R.id.btn_hint2);mShowImg= (ImageView) findViewById(R.id.img_shouw);mQRCodeResult= (TextView) findViewById(R.id.tv_result);scan.setOnClickListener(this);generate.setOnClickListener(this);}//扫描成功后震动private void vibrate() {Vibrator mVibrator= (Vibrator) getSystemService(VIBRATOR_SERVICE);mVibrator.vibrate(200);}@Overridepublic void onClick(View v) {switch (v.getId()) {//打开框扫描case R.id.btn_switch:changeLight();startActivityForResult(new Intent(ZxingActivity.this,SimpleCaptureActivity.class), 0);break;//生成二维码case R.id.btn_hint2:Handler mHandler=new Handler();mHandler.post(new Runnable() {@Overridepublic void run() {create();}});break;default:break;}}//打开扫描框需要回掉的方法@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {super.onActivityResult(requestCode, resultCode, data);if(requestCode==REQUEST_OK){Bundle bundle=data.getExtras();if (bundle!=null){String result=bundle.getString("result");mQRCodeResult.setText(result);}}}//扫描时提高屏幕的亮度public void changeLight(){WindowManager.LayoutParams lp=getWindow().getAttributes();lp.screenBrightness=1.0f;getWindow().setAttributes(lp);}private void create() {int width = DensityUtils.dip2px(this, 200);String writeContent=content.getText().toString();if (writeContent!=null) {Bitmap bitmap = EncodingUtils.createQRCode(writeContent,width, width, BitmapFactory.decodeResource(getResources(),R.mipmap.ic_launcher));mShowImg.setImageBitmap(bitmap);saveBitmap(bitmap);}else{Toast.makeText(ZxingActivity.this,"请输入你要生成二维码的文本",Toast.LENGTH_LONG).show();}}/*** 将Bitmap保存在本地*/public void saveBitmap(Bitmap bitmap) {// 首先保存图片File appDir = new File(Environment.getExternalStorageDirectory(),"zxing_image");if (!appDir.exists()) {appDir.mkdir();}String fileName = "zxing_image" + ".jpg";File file = new File(appDir, fileName);try {FileOutputStream fos = new FileOutputStream(file);bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);fos.flush();fos.close();} catch (Exception e) {e.printStackTrace();}// 把文件插入到系统图库try {MediaStore.Images.Media.insertImage(this.getContentResolver(),file.getAbsolutePath(), fileName, null);} catch (Exception e) {e.printStackTrace();}// 通知图库更新sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE,Uri.parse("file://" + "/sdcard/namecard/")));}}

比较重要的写了点注释，帮助理解吧

EncodingUtils.java这个工具是从一个地方down过来的，很不错，分享给大家吧

/*** 二维码生成工具类*/public class EncodingUtils {public static Bitmap createQRCode(String content, int widthPix, int heightPix, Bitmap logoBm) {try {if (content == null || "".equals(content)) {return null;}// 配置参数Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>();hints.put(EncodeHintType.CHARACTER_SET, "utf-8");// 容错级别hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);// 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_8888Bitmap 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;} catch (WriterException e) {e.printStackTrace();}return null;}/*** 在二维码中间添加Logo图案*/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1/5float 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;}}

到这里核心的代码就没了，但是这时候大家会发现没有SimpleCaptureActivity.java这个类，本来我们打开扫描框本来可是使用startActivityForResult(new Intent(ZxingActivity.this,CaptureActivity.class),0）来实现，但是你会发现这个扫描框的样式很吓人，因此我们通常就需要定义SimpleCaptureActivity.java继承CaptureActivity来实现比较好看的样式，注意在导入包时候一定要导入

import io.github.xudaojie.qrcodelib.CaptureActivity中的，负责样式会很吓人的。好接下来咱看一下Sim。的的代码吧！

ublic class SimpleCaptureActivity extends CaptureActivity {protected Activity mActivity = this;private AlertDialog mDialog;@Overridepublic void onCreate(Bundle savedInstanceState) {mActivity = this;super.onCreate(savedInstanceState);}@Overrideprotected void handleResult(String resultString) {if (TextUtils.isEmpty(resultString)) {Toast.makeText(mActivity, io.github.xudaojie.qrcodelib.R.string.scan_failed, Toast.LENGTH_SHORT).show();restartPreview();} else {if (mDialog == null) {mDialog = new AlertDialog.Builder(mActivity).setMessage(resultString).setPositiveButton("确定", null).create();mDialog.setOnDismissListener(new DialogInterface.OnDismissListener() {@Overridepublic void onDismiss(DialogInterface dialog) {restartPreview();}});}if (!mDialog.isShowing()) {mDialog.setMessage(resultString);mDialog.show();}}}}

Okay，这样简单的二维码的扫描和生成几乎已经搞定了，但是不要着急，你还需要在你的配置文件中添加适当的权限。

<!-- 二维码的权限 --><uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /><uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /><uses-permission android:name="android.permission.CAMERA" /><uses-permission android:name="android.permission.VIBRATE" />

这样就大致搞定了一个简单的二维码的效果。仅供参考哈。