主要修改onDraw方法里面的属性……
/** * 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 int[] SCANNER_ALPHA = {0, 64, 128, 192, 255, 192, 128, 64}; private static final long ANIMATION_DELAY = 100L; private static final int OPAQUE = 0xFF; private final Paint paint; private Bitmap resultBitmap; private final int maskColor; private final int resultColor; private final int frameColor; private final int laserColor; private final int resultPointColor; private int scannerAlpha; private Collection<ResultPoint> possibleResultPoints; private Collection<ResultPoint> lastPossibleResultPoints; // This constructor is used when the class is built from an XML resource. public ViewfinderView(Context context, AttributeSet attrs) { super(context, attrs); // Initialize these once for performance rather than calling them every time in onDraw(). paint = new Paint(); Resources resources = getResources(); maskColor = resources.getColor(R.color.viewfinder_mask); resultColor = resources.getColor(R.color.result_view); frameColor = resources.getColor(R.color.viewfinder_frame); laserColor = resources.getColor(R.color.viewfinder_laser); resultPointColor = resources.getColor(R.color.possible_result_points); scannerAlpha = 0; possibleResultPoints = new HashSet<ResultPoint>(5); } /** * 中间那条线每次刷新移动的距离 */ private static final int SPEEN_DISTANCE = 20; /** * 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; /** * 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 = 10; boolean isFirst; @Override public void onDraw(Canvas canvas) { 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(); // Draw the exterior (i.e. outside the framing rect) darkened //画出扫描框外面的阴影部分 paint.setColor(resultBitmap != null ? resultColor : maskColor); 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 { //绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE paint.setColor(laserColor); slideTop += SPEEN_DISTANCE; if (slideTop >= frame.bottom) { slideTop = frame.top; } canvas.drawRect(frame.left + 2, slideTop - 1, frame.right - 1, slideTop + 2, paint); // 画出四个角 // Draw four corners paint.setColor(getResources().getColor(R.color.colorBillStatus1)); // 左上角(top left corner) canvas.drawRect(frame.left, frame.top, frame.left + 35, frame.top + 8, paint); canvas.drawRect(frame.left, frame.top, frame.left + 8, frame.top + 35, paint); // 右上角(top right corner) canvas.drawRect(frame.right - 35, frame.top, frame.right, frame.top + 8, paint); canvas.drawRect(frame.right - 8, frame.top, frame.right, frame.top + 35, paint); // 左下角(Bottom left corner) canvas.drawRect(frame.left, frame.bottom - 8, frame.left + 35, frame.bottom, paint); canvas.drawRect(frame.left, frame.bottom - 35, frame.left + 8, frame.bottom, paint); // 右下角(Bottom right corner) canvas.drawRect(frame.right - 35, frame.bottom - 8, frame.right, frame.bottom, paint); canvas.drawRect(frame.right - 8, frame.bottom - 35, frame.right, frame.bottom, 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); } } // Request another update at the animation interval, but only repaint the laser line, // not the entire viewfinder mask. //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); } }
