二维码扫描慢解决办法

CameraManager.java

public Rect getFramingRect()//预览区域。也就是扫面是画的那个框

public Rect getFramingRectInPreview()//扫描采集区。也就是你的扫描区

这两个方法一个设置预览框大小，一个设置实际扫描区域，把实际扫描区域弄成全屏，把扫描框自定义下大小，让用户将二维码放入识别框，这就让用户不得不拉远距离，实际上从二维码进入镜头就开始识别了，提高了识别率。

下面给出调整大小的方法：

public Rect getFramingRect()
    {
        Point screenResolution = configManager.getScreenResolution();
        if(framingRect == null)
        {
            if(camera == null)
            {
                return null;
            }
            DisplayMetrics metrics = context.getResources().getDisplayMetrics();

            // 控制宽高
            int width = (int) (metrics.widthPixels * 0.3);
            int height = (int) (width * 0.9);
            
            // 控制位置
            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;
    }

    /**
     * 扫描识别采集区。也就是你的扫描区
     * Like {@link #getFramingRect} but coordinates are in terms of the preview frame,
     * not UI / screen.
     */
    public Rect getFramingRectInPreview()
    {
        if(framingRectInPreview == null)
        {
            Point screenResolution = configManager.getScreenResolution();
            DisplayMetrics metrics = context.getResources().getDisplayMetrics();

            // 控制宽高
            int width = (int) (metrics.widthPixels * 1);
            int height = (int) (metrics.heightPixels * 1);
            
            // 控制位置
            int leftOffset = (screenResolution.x - width) / 2;
            int topOffset = (screenResolution.y - height) / 2;
            framingRectInPreview = new Rect(leftOffset, topOffset, leftOffset + width, topOffset + height);
        }
        return framingRectInPreview;
    }