Zxing掃描和生成二維碼+butterknife8.0之後的引用

**最近項目中用到二維碼掃描和生成使用到了Zxing這裏記錄下來：
先貼官方地址：**官網地址開源中國 github.

項目下載地址：http://download.csdn.net/detail/u010023795/9679251

我這裏只集成了掃碼和二維碼生成的功能這裏主要用到的兩個類：CaptureActivity 掃描和EncodingUtils生成：“
* /*
public final class CaptureActivity extends Activity implements SurfaceHolder.Callback {

private static final String TAG = CaptureActivity.class.getSimpleName();

private CameraManager cameraManager;
private CaptureActivityHandler handler;
private InactivityTimer inactivityTimer;
private BeepManager beepManager;

private SurfaceView scanPreview = null;
private RelativeLayout scanContainer;
private RelativeLayout scanCropView;
private ImageView scanLine;

private Rect mCropRect = null;
private boolean isHasSurface = false;

public Handler getHandler() {
return handler;
}

public CameraManager getCameraManager() {
return cameraManager;
}

@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
```
Window window = getWindow();
window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.activity_capture);

scanPreview = (SurfaceView) findViewById(R.id.capture_preview);
scanContainer = (RelativeLayout) findViewById(R.id.capture_container);
scanCropView = (RelativeLayout) findViewById(R.id.capture_crop_view);
scanLine = (ImageView) findViewById(R.id.capture_scan_line);

inactivityTimer = new InactivityTimer(this);
beepManager = new BeepManager(this);

TranslateAnimation animation = new TranslateAnimation(Animation.RELATIVE_TO_PARENT, 0.0f, Animation
        .RELATIVE_TO_PARENT, 0.0f, Animation.RELATIVE_TO_PARENT, 0.0f, Animation.RELATIVE_TO_PARENT,
        0.9f);
animation.setDuration(4500);
animation.setRepeatCount(-1);
animation.setRepeatMode(Animation.RESTART);
scanLine.startAnimation(animation);
```
}

@Override
protected void onResume() {
super.onResume();
```
// CameraManager must be initialized here, not in onCreate(). This is
// necessary because we don't
// want to open the camera driver and measure the screen size if we're
// going to show the help on
// first launch. That led to bugs where the scanning rectangle was the
// wrong size and partially
// off screen.
cameraManager = new CameraManager(getApplication());


handler = null;

if (isHasSurface) {
    // The activity was paused but not stopped, so the surface still
    // exists. Therefore
    // surfaceCreated() won't be called, so init the camera here.
    initCamera(scanPreview.getHolder());
} else {
    // Install the callback and wait for surfaceCreated() to init the
    // camera.
    scanPreview.getHolder().addCallback(this);
}

inactivityTimer.onResume();
```
}

@Override
protected void onPause() {
if (handler != null) {
handler.quitSynchronously();
handler = null;
}
inactivityTimer.onPause();
beepManager.close();
cameraManager.closeDriver();
if (!isHasSurface) {
scanPreview.getHolder().removeCallback(this);
}
super.onPause();
}

@Override
protected void onDestroy() {
inactivityTimer.shutdown();
super.onDestroy();
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
if (holder == null) {
Log.e(TAG, “* WARNING * surfaceCreated() gave us a null surface!”);
}
if (!isHasSurface) {
isHasSurface = true;
initCamera(holder);
}
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
isHasSurface = false;
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

}

/**
- A valid barcode has been found, so give an indication of success and show
- the results.
  *
- @param rawResult The contents of the barcode.
- @param bundle The extras
  */
  public void handleDecode(Result rawResult, Bundle bundle) {
  inactivityTimer.onActivity();
  beepManager.playBeepSoundAndVibrate();
  /*
  這裏是掃描成功之後返回數據給界面，需要返回的數據在這裏添加
  */
  Intent resultIntent = new Intent();
  bundle.putInt(“width”, mCropRect.width()); //返回生成二維碼掃描框的寬
  bundle.putInt(“height”, mCropRect.height());//返回生成二維碼掃描框的高
  bundle.putString(“result”, rawResult.getText());//返回二維碼的內容
  resultIntent.putExtras(bundle);
  this.setResult(RESULT_OK, resultIntent);
  CaptureActivity.this.finish();
  }
private void initCamera(SurfaceHolder surfaceHolder) {
if (surfaceHolder == null) {
throw new IllegalStateException(“No SurfaceHolder provided”);
}
if (cameraManager.isOpen()) {
Log.w(TAG, “initCamera() while already open – late SurfaceView callback?”);
return;
}
try {
cameraManager.openDriver(surfaceHolder);
// Creating the handler starts the preview, which can also throw a
// RuntimeException.
if (handler == null) {
handler = new CaptureActivityHandler(this, cameraManager, DecodeThread.ALL_MODE);
}
```
    initCrop();
} catch (IOException ioe) {
    Log.w(TAG, ioe);
    displayFrameworkBugMessageAndExit();
} catch (RuntimeException e) {
    // Barcode Scanner has seen crashes in the wild of this variety:
    // java.?lang.?RuntimeException: Fail to connect to camera service
    Log.w(TAG, "Unexpected error initializing camera", e);
    displayFrameworkBugMessageAndExit();
}
```
}

private void displayFrameworkBugMessageAndExit() {
// camera error
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle(getString(R.string.app_name));
builder.setMessage(“Camera error”);
builder.setPositiveButton(“OK”, new DialogInterface.OnClickListener() {
```
    @Override
    public void onClick(DialogInterface dialog, int which) {
        finish();
    }

});
builder.setOnCancelListener(new DialogInterface.OnCancelListener() {

    @Override
    public void onCancel(DialogInterface dialog) {
        finish();
    }
});
builder.show();
```
}

public void restartPreviewAfterDelay(long delayMS) {
if (handler != null) {
handler.sendEmptyMessageDelayed(R.id.restart_preview, delayMS);
}
}

public Rect getCropRect() {
return mCropRect;
}

/**
- 初始化截取的矩形區域
  */
  private void initCrop() {
  int cameraWidth = cameraManager.getCameraResolution().y;
  int cameraHeight = cameraManager.getCameraResolution().x;
  
  /* 獲取佈局中掃描框的位置信息 /
  int[] location = new int[2];
  scanCropView.getLocationInWindow(location);
  
  int cropLeft = location[0];
  int cropTop = location[1] - getStatusBarHeight();
  
  int cropWidth = scanCropView.getWidth();
  int cropHeight = scanCropView.getHeight();
  
  /* 獲取佈局容器的寬高 /
  int containerWidth = scanContainer.getWidth();
  int containerHeight = scanContainer.getHeight();
  
  /* 計算最終截取的矩形的左上角頂點x座標 /
  int x = cropLeft * cameraWidth / containerWidth;
  /* 計算最終截取的矩形的左上角頂點y座標 /
  int y = cropTop * cameraHeight / containerHeight;
  
  /* 計算最終截取的矩形的寬度 /
  int width = cropWidth * cameraWidth / containerWidth;
  /* 計算最終截取的矩形的高度 /
  int height = cropHeight * cameraHeight / containerHeight;
  
  /* 生成最終的截取的矩形 /
  mCropRect = new Rect(x, y, width + x, height + y);
  }
  private int getStatusBarHeight() {
  try {
  Class <> c = Class.forName(“com.android.internal.R$dimen”);//class<>裏面爲？
  Object obj = c.newInstance();
  Field field = c.getField(“status_bar_height”);
  int x = Integer.parseInt(field.get(obj).toString());
  return getResources().getDimensionPixelSize(x);
  } catch (Exception e) {
  e.printStackTrace();
  }
  return 0;
  }
  }
  
  下面是二維碼生成工具類：
  /**
  - 二維碼生成工具類
    */
    public class EncodingUtils {
/**
- 創建二維碼
  *
- @param content content
- @param widthPix widthPix
- @param heightPix heightPix
- @param logoBm logoBm
- @return 二維碼
  */
  public static Bitmap createQRCode(String content, int widthPix, int heightPix, Bitmap logoBm) {
  try {
  if (content == null || “”.equals(content)) {
  return null;
  }
  // 配置參數
  Map<> hints = new HashMap<>();//Map<>括號裏應該是EncodeHintType, Object不知道爲什麼csdn裏面這樣直接這樣寫會造成下面的內容全部不顯示
  hints.put(EncodeHintType.CHARACTER_SET, “utf-8”);
  // 容錯級別
  hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
  // 圖像數據轉換，使用了矩陣轉換
  BitMatrix bitMatrix = new QRCodeWriter().encode(content, BarcodeFormat.QR_CODE, widthPix,
  heightPix, hints);
  int[] pixels = new int[widthPix * heightPix];
  // 下面這裏按照二維碼的算法，逐個生成二維碼的圖片，
  // 兩個for循環是圖片橫列掃描的結果
  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;
  }
  }
  }
  // 生成二維碼圖片的格式，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);
  }
  //必須使用compress方法將bitmap保存到文件中再進行讀取。直接返回的bitmap是沒有任何壓縮的，內存消耗巨大！
  return bitmap;
  } catch (WriterException e) {
  e.printStackTrace();
  }
  return null;
  }
/**
- 在二維碼中間添加Logo圖案
  */
  private static Bitmap addLogo(Bitmap src, Bitmap logo) {
  if (src == null) {
  return null;
  }
  if (logo == null) {
  return src;
  }
  //獲取圖片的寬高
  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大小爲二維碼整體大小的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;
  }
  }

這些類都是Zxing裏面的，自己可以根據需要去封裝。

封裝好了類之後其實我們的調用就很簡單了只需要寫一個Activity。
public class MainActivity extends AppCompatActivity {

@BindView(R.id.btn_camer)
Button btnCamer;
@BindView(R.id.tv_result)
TextView tvResult;
@BindView(R.id.et_qr_string)
EditText etQrString;
@BindView(R.id.btn_creat)
Button btnCreat;
@BindView(R.id.if_logo)
CheckBox ifLogo;
@BindView(R.id.iamge_show)
ImageView iamgeShow;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    ButterKnife.bind(this); 

}


@OnClick({R.id.btn_camer, R.id.btn_creat, R.id.if_logo, R.id.iamge_show})
public void onClick(View view) {
    switch (view.getId()) {
        case R.id.btn_camer:
            startActivityForResult(new Intent(MainActivity.this, CaptureActivity.class),0);//啓動掃描界面
            break;
        case R.id.btn_creat:
            String str = etQrString.getText().toString();
            if (str.equals("")) {
                Toast.makeText(MainActivity.this, "不能爲空", Toast.LENGTH_SHORT).show();
            } else {
                // 位圖
                try {
                    /**
                     * 參數：1.文本 2 3.二維碼的寬高 4.二維碼中間的那個logo
                     */
                    Bitmap bitma = BitmapFactory.decodeResource(getResources(), R.drawable.zaizai);
                    Bitmap bitmap = EncodingUtils.createQRCode(str, 700, 700,bitma);
                    // 設置圖片
                    iamgeShow.setImageBitmap(bitmap);
                    Toast.makeText(this,"55555"+str,Toast.LENGTH_SHORT).show();
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            Toast.makeText(this,"55555",Toast.LENGTH_SHORT).show();
            break;
        case R.id.if_logo:
            break;
        case R.id.iamge_show:
            break;
    }
}
/*
掃描成功之後返回二維碼的信息在這裏接收處理
 */
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == RESULT_OK) {
        String result = data.getExtras().getString("result");
        Toast.makeText(this,result+"1",Toast.LENGTH_SHORT).show();
        tvResult.setText(result);
    }
}

}

二維碼生成和掃描就這麼寫完了，但是在運行的時候竟然報控件空指針錯誤，就是說我的控件都是沒有生成找不到的在運行的時候，但是我明明用了ButterKnife也添加進去了還可以自動生成，但是註解運行的時候就是沒成功。後來找到了資料，原來在ButterKnife8.0以後引用發生了改變。現在必需多做幾道程序下面請看圖：
先把官網地址貼出來：http://jakewharton.github.io/butterknife/
github：https://github.com/JakeWharton/butterknife

接下來我們打開第一個gradle
添加classpath ‘com.neenbedankt.gradle.plugins:android-apt:1.8’

第二步打開第二個gradle
apply plugin: ‘com.neenbedankt.android-apt’
compile ‘com.jakewharton:butterknife:8.4.0’
apt ‘com.jakewharton:butterknife-compiler:8.4.0’

最後注意添加的版本是不是一致，兩個gradle中Butter Knife版本必須一致。最後重新 clean project就完成了。
參考：http://www.cnblogs.com/zzw1994/p/5197758.html

將drawable下的圖片轉換成bitmap
1、 Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.xxx);

2、Resources r = this.getContext().getResources();
Inputstream is = r.openRawResource(R.drawable.xxx);
BitmapDrawable bmpDraw = new BitmapDrawable(is);
Bitmap bmp = bmpDraw.getBitmap();

3、Resources r = this.getContext().getResources();
Bitmap bmp=BitmapFactory.decodeResource(r, R.drawable.icon);
Bitmap bmp = Bitmap.createBitmap( 300, 300, Config.ARGB_8888 );

將drawable下的圖片轉換成Drawable
Resources resources = mContext.getResources();
Drawable drawable = resources.getDrawable(R.drawable.a);
imageview.setBackground(drawable);

Zxing掃描和生成二維碼+butterknife8.0之後的引用+將drawable文件夾下的圖片轉換成Drawable

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