【Android-Zxing框架】二維碼掃描框區域大小與不一樣手機分辨率適配問題

Zxing框架進行二維碼掃描時候會發現，隨着分辨率的增長，掃描框會愈來愈小，SurfaceView掃描窗口就看不見了，咱們能夠本身定義掃描窗口的大小，以及適配屏幕問題。

 

 Zxing包中有個類CameraManager，它是來設置掃描框的大小

 掃描框框初始化數值

  private static  int MIN_FRAME_WIDTH = 240;
  private static  int MIN_FRAME_HEIGHT = 240;
  private static  int MAX_FRAME_WIDTH = 480;
  private static  int MAX_FRAME_HEIGHT = 360;

 

此類裏面有個getFramingRect方法用來設置掃描的框的大小，若是要修改掃描框的大小能夠在這個方法裏修改

  public Rect getFramingRect() {
    Point screenResolution = configManager.getScreenResolution();
    if (framingRect == null) {
      if (camera == null) {
        return null;
      }

      MIN_FRAME_WIDTH = Dp2Px(context,180)；
      MIN_FRAME_HEIGHT =Dp2Px(context,180)；
      MAX_FRAME_WIDTH = Dp2Px(context,280)；
      MAX_FRAME_HEIGHT =Dp2Px(context,240)；

      int width = screenResolution.x * 3 / 4;
      if (width < MIN_FRAME_WIDTH) {
        width = MIN_FRAME_WIDTH;
      } else if (width > MAX_FRAME_WIDTH) {
        width = MAX_FRAME_WIDTH;
      }
      int height = screenResolution.y * 3 / 4;
      if (height < MIN_FRAME_HEIGHT) {
        height = MIN_FRAME_HEIGHT;
      } 
        else if (height > MAX_FRAME_HEIGHT) {
        height = MAX_FRAME_HEIGHT;
      }
      int leftOffset = (screenResolution.x - width) / 2;
      int topOffset = (screenResolution.y - height) / 2;
      framingRect = new Rect(leftOffset, topOffset, leftOffset + width, topOffset + height);
      Log.d(TAG, "Calculated framing rect: " + framingRect);
    }
    return framingRect;
  }

 

要讓掃描框適應不一樣的分辨率，咱們須要根據分辨率將掃描框的初始值轉化就好。

      MIN_FRAME_WIDTH = Dp2Px(context,180);
      MIN_FRAME_HEIGHT =Dp2Px(context,180) ;
      MAX_FRAME_WIDTH = Dp2Px(context,280);
      MAX_FRAME_HEIGHT =Dp2Px(context,240) ;

dp轉爲px的方法爲

  public static  int Dp2Px( Context context,float dp) { 
        final float scale = context.getResources().getDisplayMetrics().density; 
        return (int) (dp * scale + 0.5f); 
    }