二维码这个东西自从出来后就一直流行到现在,无论走到哪里,二维码都可能出现在你的眼前。现在智能手机基本上都有扫一扫功能,扫的就是二维码。那我们怎 么样在手机上生成个自己的二维码呢?Android开发中生成二维码不难,用Google ZXing生成二维码很简单,下面我们就简单操作一直,把最主要的代码贴出来,还请大家多指教!
第一步:
确定我们二维码的位置,即是在我们应用的哪个页面的哪个位置,简单讲就是用一个ImageView把二维码展示出来,我们就把二维码展示在下面布局activity_qr_layout中的ImageView上:
- <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
- xmlns:sample="http://schemas.android.com/apk/res-auto"
- android:layout_width="match_parent"
- android:layout_height="match_parent"
- android:background="#dadada"
- android:focusable="true"
- android:focusableInTouchMode="true"
- android:orientation="vertical" >
- <ImageView
- android:id="@+id/qr_show"
- android:layout_gravity="center_horizontal"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_marginBottom="55dp"
- android:scaleType="fitXY"
- android:background="@null"
- android:src="@drawable/default_pic"
- />
- </LinearLayout>
接下来直接在Activity中生成二维码就可以了:
- public class MyQrActivity extends Activity {
- private ImageView qr_show;
- private SampleListLinearLayout lv_record;
- @Override
- protected void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- setContentView(R.layout.activity_qr_layout);
- initViews();
- }
- protected void initViews() {
- qr_show = (ImageView) findViewById(R.id.qr_show);
- DisplayMetrics outMetrics = new DisplayMetrics();
- getWindowManager().getDefaultDisplay().getMetrics(outMetrics);
- int w = outMetrics.widthPixels * 8 / 11;//设置宽度
- ViewGroup.LayoutParams layoutParams = qr_show.getLayoutParams();
- layoutParams.height = layoutParams.width = w;//设置高度
- qr_show.setLayoutParams(layoutParams);
- try {
- Bitmap bitmap = QRUtils.encodeToQRWidth("http://write.blog.csdn.net/", w);//要生成二维码的内容,我这就是一个网址
- qr_show.setImageBitmap(bitmap);
- }
- catch (Exception e) {
- e.printStackTrace();
- Toast.makeText(this, "生成二维码失败", Toast.LENGTH_SHORT);
- }
- }
- }
下面是生成二维码的工具类,不要忘记在项目中要导入ZXing相关的jar包:
- public class QRUtils {
- private static final int WHITE = 0xFFFFFFFF;
- private static final int BLACK = 0xFF000000;
- /**
- * 将字符串按照指定大小生成二维码图片
- */
- public static Bitmap encodeToQR(String contentsToEncode, int dimension) throws Exception{
- if(TextUtils.isEmpty(contentsToEncode))
- return null;
- BarcodeFormat format = BarcodeFormat.QR_CODE;
- Map<EncodeHintType,Object> hints = new EnumMap<EncodeHintType,Object>(EncodeHintType.class);
- hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
- BitMatrix result = new MultiFormatWriter().encode(contentsToEncode, format, dimension, dimension, hints);
- int width = result.getWidth();
- int height = result.getHeight();
- int[] pixels = new int[width * height];
- for (int y = 0; y < height; y++) {
- int offset = y * width;
- for (int x = 0; x < width; x++) {
- pixels[offset + x] = result.get(x, y) ? BLACK : WHITE;
- }
- }
- Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
- bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
- return bitmap;
- }
- public static Bitmap encodeToQRWidth(String contentsToEncode, int dimension) throws Exception{
- if(TextUtils.isEmpty(contentsToEncode))
- return null;
- BarcodeFormat format = BarcodeFormat.QR_CODE;
- Map<EncodeHintType,Object> hints = new EnumMap<EncodeHintType,Object>(EncodeHintType.class);
- hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
- BitMatrix result = new MultiFormatWriter().encode(contentsToEncode, format, dimension, dimension, hints);
- int width = result.getWidth();
- int height = result.getHeight();
- boolean isFirstBlack = true;
- int startX = 0;
- int startY = 0;
- int[] pixels = new int[width * height];
- for (int y = 0; y < height; y++) {
- int offset = y * width;
- for (int x = 0; x < width; x++) {
- pixels[offset + x] = result.get(x, y) ? BLACK : WHITE;
- if(result.get(x, y) && isFirstBlack){
- isFirstBlack = false;
- startX = x;
- startY = y;
- }
- }
- }
- Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
- bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
- Matrix m = new Matrix();
- float sx = (width + 2f*startX) / width;
- float sy = (height + 2f*startY) / height;
- m.postScale(sx, sy);
- Bitmap qrBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
- Canvas canvas = new Canvas(qrBitmap);
- canvas.translate(-startX, -startY);
- Paint paint = new Paint();
- paint.setAntiAlias(true);
- canvas.drawBitmap(bitmap, m, paint);
- canvas.save();
- return qrBitmap;
- }
- }
ok搞定,拿去扫一扫就可以啦!
来源: http://www.phpxs.com/code/1002256/