Android Zxing调整扫描区域优化取图速度-优快云博客

Zxing 是google提供的二维码扫描工程

Demo本身默认的扫图区域最大只有 360*480 需要拉开很远的距离才能将整个二维码扫描到

因此需要我们自己调整取图大小

在CameraManager.java这个类中进行调整

默认的大小是以下这4个参数

1

2

3

4

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

根据屏幕大小调整大家可以增大这些数值 : 最小的宽高 ; 最大宽高

参数实际在 getFramingRect() 方法中起作用

以下是原本Demo中提供的

 
        /** 
       
        * Calculates the framing rect which the UI should draw to show the user where to place the 
       
        * barcode. This target helps with alignment as well as forces the user to hold the device 
       
        * far enough away to ensure the image will be in focus. 
       
        * 
       
        * @return The rectangle to draw on screen in window coordinates. 
       
        */ 
       
        public 
         Rect getFramingRect() { 
       
        Point screenResolution = configManager.getScreenResolution(); 
       
        if 
         (framingRect ==  
        null 
        ) { 
       
        if 
         (camera ==  
        null 
        ) { 
       
        return 
         null 
        ; 
       
        } 
       
        //原生 
       
        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; 
       
        }

我为了适配不同的屏幕大小将代码改成了

 
        public 
         Rect getFramingRect() { 
       
        Point screenResolution = configManager.getScreenResolution(); 
       
        if 
         (framingRect ==  
        null 
        ) { 
       
        if 
         (camera ==  
        null 
        ) { 
       
        return 
         null 
        ; 
       
        } 
       
        //修改之后   
       
        int 
         width = screenResolution.x *  
        7 
         /  
        10 
        ; 
       
        int 
         height = screenResolution.y *  
        7 
         /  
        10 
        ; 
       
        int 
         leftOffset = (screenResolution.x - width) /  
        2 
        ; 
       
        int 
         topOffset = (screenResolution.y - height) /  
        3 
        ; 
       
        framingRect =  
        new 
         Rect(leftOffset, topOffset, leftOffset + width, topOffset + height); 
       
        Log.d(TAG,  
        "Calculated framing rect: " 
         + framingRect); 
       
        } 
       
        return 
         framingRect; 
       
        }