Android基于google Zxing实现各类二维码扫描效果

2020-04-11 10:48:41

字体：大中小

来源：转载

供稿：网友

随着微信的到来，二维码越来越火爆，随处能看到二维码，比如商城里面，肯德基，餐厅等等，对于二维码扫描我们使用的是google的开源框架Zxing,我们可以去http://code.google.com/p/zxing/下载源码和Jar包，之前我项目中的二维码扫描功能只实现了扫描功能，其UI真的是其丑无比，一个好的应用软件，其UI界面也要被大众所接纳，不然人家就不会用你的软件啦，所以说应用软件功能和界面一样都很重要，例如微信，相信微信UI被很多应用软件所模仿，我也仿照微信扫描二维码效果进行模仿，虽然没有微信做的那么精致，但是效果还是可以的，所以将自己修改UI的代码和扫描二维码的代码分享给大家，一是自己以后项目遇到同样的功能直接拷贝来用，二是给还没有加入二维码功能的人一个参考，站在巨人的肩膀上,哈哈，我之前也是站在巨人的肩膀上加上此功能，接下来跟着我一步一步来实现此项功能，里面去除了很多不必要的文件

我们先看下项目的结构

如果你项目也想加入此功能，你直接将com.mining.app.zxing.camera，com.mining.app.zxing.decoding，com.mining.app.zxing.view这三个包拷贝到你的项目中，然后引入相对应的资源进去，我也是从我的项目中直接引用过来的，包名都没改呢，当然还需要引用Zxing.jar
com.example.qr_codescan包里面有一个MipcaActivityCapture,也是直接引入我之前项目的代码的，这个Activity主要处理扫描界面的类，比如，扫描成功有声音和振动等等，主要关注里面的handleDecode(Result result, Bitmap barcode)方法，扫描完成之后将扫描到的结果和二维码的bitmap当初参数传递到handleDecode(Result result, Bitmap barcode)里面，我们只需要在里面写出相对应的处理代码即可，其他的地方都不用改得，我这里处理扫描结果和扫描拍的照片

/**  * 处理扫描结果  * @param result  * @param barcode  */ public void handleDecode(Result result, Bitmap barcode) {  inactivityTimer.onActivity();  playBeepSoundAndVibrate();  String resultString = result.getText();  if (resultString.equals("")) {   Toast.makeText(MipcaActivityCapture.this, "Scan failed!", Toast.LENGTH_SHORT).show();  }else {   Intent resultIntent = new Intent();   Bundle bundle = new Bundle();   bundle.putString("result", resultString);   bundle.putParcelable("bitmap", barcode);   resultIntent.putExtras(bundle);   this.setResult(RESULT_OK, resultIntent);  }  MipcaActivityCapture.this.finish(); }

我对MipcaActivityCapture界面的布局做了自己的改动，先看下效果图，主要是用到FrameLayout,里面嵌套RelativeLayout。

布局代码如下

<?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"  android:layout_width="fill_parent"   android:layout_height="fill_parent" >   <RelativeLayout   android:layout_width="fill_parent"   android:layout_height="fill_parent" >    <SurfaceView    android:id="@+id/preview_view"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:layout_gravity="center" />    <com.mining.app.zxing.view.ViewfinderView    android:id="@+id/viewfinder_view"    android:layout_width="wrap_content"    android:layout_height="wrap_content" />    <include    android:id="@+id/include1"    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:layout_alignParentTop="true"    layout="@layout/activity_title" />  </RelativeLayout>  </FrameLayout>

在里面我将界面上面部分写在另一个布局里面，然后include进来，因为这个activity_title在我项目里面还供其他的Activity使用，我也是直接拷贝出来的

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:background="@drawable/mmtitle_bg_alpha" >   <Button   android:id="@+id/button_back"   android:layout_width="75.0dip"   android:text="返回"   android:background="@drawable/mm_title_back_btn"   android:textColor="@android:color/white"   android:layout_height="wrap_content"   android:layout_centerVertical="true"   android:layout_marginLeft="2dip" />   <TextView   android:id="@+id/textview_title"   android:layout_width="wrap_content"   android:layout_height="wrap_content"   android:layout_alignBaseline="@+id/button_back"   android:layout_alignBottom="@+id/button_back"   android:layout_centerHorizontal="true"   android:gravity="center_vertical"   android:text="二维码扫描"   android:textColor="@android:color/white"   android:textSize="18sp" />  </RelativeLayout>

在我这个demo里面，有一个主界面MainActivity，里面一个Button，一个ImageView和一个TextView,点击Button进入到二维码扫描界面，当扫描OK的时候，回到主界面，将扫描的结果显示到TextView，将图片显示到ImageView里面，然后你可以不处理图片，我这里随带的加上图片，主界面的布局很简单如下

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:background="#ffe1e0de" >   <Button   android:id="@+id/button1"   android:layout_width="fill_parent"   android:layout_height="wrap_content"   android:layout_alignParentTop="true"   android:text="扫描二维码" />   <TextView   android:id="@+id/result"   android:layout_width="fill_parent"   android:layout_height="wrap_content"   android:layout_below="@+id/button1"   android:lines="2"   android:gravity="center_horizontal"   android:textColor="@android:color/black"   android:textSize="16sp" />   <ImageView   android:id="@+id/qrcode_bitmap"   android:layout_width="fill_parent"   android:layout_height="fill_parent"   android:layout_alignParentLeft="true"   android:layout_below="@+id/result"/> </RelativeLayout>

MainActivity里面的代码如下，里面的功能在上面已经说了

package com.example.qr_codescan;   import android.app.Activity; import android.content.Intent; import android.graphics.Bitmap; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.ImageView; import android.widget.TextView;  public class MainActivity extends Activity {  private final static int SCANNIN_GREQUEST_CODE = 1;  /**   * 显示扫描结果   */  private TextView mTextView ;  /**   * 显示扫描拍的图片   */  private ImageView mImageView;     @Override  protected void onCreate(Bundle savedInstanceState) {   super.onCreate(savedInstanceState);   setContentView(R.layout.activity_main);      mTextView = (TextView) findViewById(R.id.result);   mImageView = (ImageView) findViewById(R.id.qrcode_bitmap);      //点击按钮跳转到二维码扫描界面，这里用的是startActivityForResult跳转   //扫描完了之后调到该界面   Button mButton = (Button) findViewById(R.id.button1);   mButton.setOnClickListener(new OnClickListener() {        @Override    public void onClick(View v) {     Intent intent = new Intent();     intent.setClass(MainActivity.this, MipcaActivityCapture.class);     intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);     startActivityForResult(intent, SCANNIN_GREQUEST_CODE);    }   });  }      @Override  protected void onActivityResult(int requestCode, int resultCode, Intent data) {   super.onActivityResult(requestCode, resultCode, data);   switch (requestCode) {   case SCANNIN_GREQUEST_CODE:    if(resultCode == RESULT_OK){     Bundle bundle = data.getExtras();     //显示扫描到的内容     mTextView.setText(bundle.getString("result"));     //显示     mImageView.setImageBitmap((Bitmap) data.getParcelableExtra("bitmap"));    }    break;   }  }   }

上面的代码还是比较简单，但是要想做出像微信那样只的扫描框，紧紧上面的代码是没有那种效果的，我们必须重写com.mining.app.zxing.view包下面的ViewfinderView类，微信里面的都是用的图片，我是自己画出来的，代码注释的比较清楚，大家直接看代码吧，相信你能理解的，如果你要修改扫描框的大小，去CameraManager类里面修改

/*  * Copyright (C) 2008 ZXing authors  *  * Licensed under the Apache License, Version 2.0 (the "License");  * you may not use this file except in compliance with the License.  * You may obtain a copy of the License at  *  *  *  * Unless required by applicable law or agreed to in writing, software  * distributed under the License is distributed on an "AS IS" BASIS,  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  * See the License for the specific language governing permissions and  * limitations under the License.  */  package com.mining.app.zxing.view;  import java.util.Collection; import java.util.HashSet;  import android.content.Context; import android.content.res.Resources; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Rect; import android.graphics.Typeface; import android.util.AttributeSet; import android.view.View;  import com.example.qr_codescan.R; import com.google.zxing.ResultPoint; import com.mining.app.zxing.camera.CameraManager;  /**  * This view is overlaid on top of the camera preview. It adds the viewfinder  * rectangle and partial transparency outside it, as well as the laser scanner  * animation and result points.  *  */ public final class ViewfinderView extends View {  private static final String TAG = "log";  /**   * 刷新界面的时间   */  private static final long ANIMATION_DELAY = 10L;  private static final int OPAQUE = 0xFF;   /**   * 四个绿色边角对应的长度   */  private int ScreenRate;    /**   * 四个绿色边角对应的宽度   */  private static final int CORNER_WIDTH = 10;  /**   * 扫描框中的中间线的宽度   */  private static final int MIDDLE_LINE_WIDTH = 6;    /**   * 扫描框中的中间线的与扫描框左右的间隙   */  private static final int MIDDLE_LINE_PADDING = 5;    /**   * 中间那条线每次刷新移动的距离   */  private static final int SPEEN_DISTANCE = 5;    /**   * 手机的屏幕密度   */  private static float density;  /**   * 字体大小   */  private static final int TEXT_SIZE = 16;  /**   * 字体距离扫描框下面的距离   */  private static final int TEXT_PADDING_TOP = 30;    /**   * 画笔对象的引用   */  private Paint paint;    /**   * 中间滑动线的最顶端位置   */  private int slideTop;    /**   * 中间滑动线的最底端位置   */  private int slideBottom;    private Bitmap resultBitmap;  private final int maskColor;  private final int resultColor;    private final int resultPointColor;  private Collection<ResultPoint> possibleResultPoints;  private Collection<ResultPoint> lastPossibleResultPoints;   boolean isFirst;    public ViewfinderView(Context context, AttributeSet attrs) {   super(context, attrs);      density = context.getResources().getDisplayMetrics().density;   //将像素转换成dp   ScreenRate = (int)(20 * density);    paint = new Paint();   Resources resources = getResources();   maskColor = resources.getColor(R.color.viewfinder_mask);   resultColor = resources.getColor(R.color.result_view);    resultPointColor = resources.getColor(R.color.possible_result_points);   possibleResultPoints = new HashSet<ResultPoint>(5);  }   @Override  public void onDraw(Canvas canvas) {   //中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改   Rect frame = CameraManager.get().getFramingRect();   if (frame == null) {    return;   }      //初始化中间线滑动的最上边和最下边   if(!isFirst){    isFirst = true;    slideTop = frame.top;    slideBottom = frame.bottom;   }      //获取屏幕的宽和高   int width = canvas.getWidth();   int height = canvas.getHeight();    paint.setColor(resultBitmap != null ? resultColor : maskColor);      //画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面   //扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边   canvas.drawRect(0, 0, width, frame.top, paint);   canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);   canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1,     paint);   canvas.drawRect(0, frame.bottom + 1, width, height, paint);          if (resultBitmap != null) {    // Draw the opaque result bitmap over the scanning rectangle    paint.setAlpha(OPAQUE);    canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);   } else {     //画扫描框边上的角，总共8个部分    paint.setColor(Color.GREEN);    canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate,      frame.top + CORNER_WIDTH, paint);    canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH, frame.top      + ScreenRate, paint);    canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right,      frame.top + CORNER_WIDTH, paint);    canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right, frame.top      + ScreenRate, paint);    canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left      + ScreenRate, frame.bottom, paint);    canvas.drawRect(frame.left, frame.bottom - ScreenRate,      frame.left + CORNER_WIDTH, frame.bottom, paint);    canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH,      frame.right, frame.bottom, paint);    canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate,      frame.right, frame.bottom, paint);         //绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE    slideTop += SPEEN_DISTANCE;    if(slideTop >= frame.bottom){     slideTop = frame.top;    }    canvas.drawRect(frame.left + MIDDLE_LINE_PADDING, slideTop - MIDDLE_LINE_WIDTH/2, frame.right - MIDDLE_LINE_PADDING,slideTop + MIDDLE_LINE_WIDTH/2, paint);            //画扫描框下面的字    paint.setColor(Color.WHITE);    paint.setTextSize(TEXT_SIZE * density);    paint.setAlpha(0x40);    paint.setTypeface(Typeface.create("System", Typeface.BOLD));    canvas.drawText(getResources().getString(R.string.scan_text), frame.left, (float) (frame.bottom + (float)TEXT_PADDING_TOP *density), paint);             Collection<ResultPoint> currentPossible = possibleResultPoints;    Collection<ResultPoint> currentLast = lastPossibleResultPoints;    if (currentPossible.isEmpty()) {     lastPossibleResultPoints = null;    } else {     possibleResultPoints = new HashSet<ResultPoint>(5);     lastPossibleResultPoints = currentPossible;     paint.setAlpha(OPAQUE);     paint.setColor(resultPointColor);     for (ResultPoint point : currentPossible) {      canvas.drawCircle(frame.left + point.getX(), frame.top        + point.getY(), 6.0f, paint);     }    }    if (currentLast != null) {     paint.setAlpha(OPAQUE / 2);     paint.setColor(resultPointColor);     for (ResultPoint point : currentLast) {      canvas.drawCircle(frame.left + point.getX(), frame.top        + point.getY(), 3.0f, paint);     }    }         //只刷新扫描框的内容，其他地方不刷新    postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top,      frame.right, frame.bottom);       }  }   public void drawViewfinder() {   resultBitmap = null;   invalidate();  }   /**   * Draw a bitmap with the result points highlighted instead of the live   * scanning display.   *   * @param barcode   *   An image of the decoded barcode.   */  public void drawResultBitmap(Bitmap barcode) {   resultBitmap = barcode;   invalidate();  }   public void addPossibleResultPoint(ResultPoint point) {   possibleResultPoints.add(point);  }  }

上面的代码中，中间那根线微信是用的图片，我这里是画的，如果你想更加仿真点就将下面的代码

canvas.drawRect(frame.left + MIDDLE_LINE_PADDING, slideTop - MIDDLE_LINE_WIDTH/2, frame.right - MIDDLE_LINE_PADDING,slideTop + MIDDLE_LINE_WIDTH/2, paint);

改成

Rect lineRect = new Rect();    lineRect.left = frame.left;    lineRect.right = frame.right;    lineRect.top = slideTop;    lineRect.bottom = slideTop + 18;    canvas.drawBitmap(((BitmapDrawable)(getResources().getDrawable(R.drawable.qrcode_scan_line))).getBitmap(), null, lineRect, paint);

那条扫描线自己去微信里面找一下，我贴出来的失真了，下载微信apk,将后缀名改成zip,然后解压就行了
画扫描框下面字体的代码需要修改下，这样子能根据字体自动排列在中间，如果字太长我没有处理，那个要自动换行，你可以自行处理

paint.setColor(Color.WHITE); paint.setTextSize(TEXT_SIZE * density); paint.setAlpha(0x40); paint.setTypeface(Typeface.DEFAULT_BOLD); String text = getResources().getString(R.string.R.string.scan_text); float textWidth = paint.measureText(text);  canvas.drawText(text, (width - textWidth)/2, (float) (frame.bottom + (float)TEXT_PADDING_TOP *density), paint)

运行界面截图，其中中间的那根绿色的线会上下移动，跟微信的效果差不多，当然运行你还需要相对应的权限问题。