Android 二维码扫描框 加四个角及中间横线自动下滑

 

 红色为加四个角  黄色为扫描线自动下滑

 

/* * Copyright (C) 2008 ZXing authors * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package com.zxing.view;import java.util.Collection;import java.util.HashSet;import android.content.Context;import android.content.res.Resources;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Rect;import android.util.AttributeSet;import android.view.View;import com.bawei.zxingdemo.R;import com.google.zxing.ResultPoint;import com.zxing.camera.CameraManager;/** * 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. 锟皆讹拷锟斤拷锟絍iew锟斤拷锟斤拷锟斤拷时锟叫硷拷锟斤拷示锟斤拷 */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;    /**      * 四个绿色边角对应的长度      */      private int ScreenRate;            /**      * 四个绿色边角对应的宽度      */      private static final int CORNER_WIDTH = 10;      /**      * 手机的屏幕密度      */      private static float density;      private Collection<ResultPoint> possibleResultPoints;    private Collection<ResultPoint> lastPossibleResultPoints;    int  count=0;    // 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);          density = context.getResources().getDisplayMetrics().density;              //将像素转换成dp              ScreenRate = (int)(20 * density);     }    @Override    public void onDraw(Canvas canvas) {        // 涓棿鐨勬壂鎻忔锛屼綘瑕佷慨鏀规壂鎻忔鐨勫ぇ灏忥紝鍘籆ameraManager閲岄潰淇敼        Rect frame = CameraManager.get().getFramingRect();        if (frame == null) {            return;        }        // 鑾峰彇灞忓箷鐨勫鍜岄珮        int width = canvas.getWidth();        int height = canvas.getHeight();        // Draw the exterior (i.e. outside the framing rect) darkened        //鐢诲嚭鎵弿妗嗗闈㈢殑闃村奖閮ㄥ垎锛屽叡鍥涗釜閮ㄥ垎锛屾壂鎻忔鐨勪笂闈㈠埌灞忓箷涓婇潰锛屾壂鎻忔鐨勪笅闈㈠埌灞忓箷涓嬮潰          //鎵弿妗嗙殑宸﹁竟闈㈠埌灞忓箷宸﹁竟锛屾壂鎻忔鐨勫彸杈瑰埌灞忓箷鍙宠竟          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 {            //鐢绘壂鎻忔杈逛笂鐨勮锛屾�诲叡8涓儴鍒�             // Draw a two pixel solid black border inside the framing rect            paint.setColor(frameColor);            canvas.drawRect(frame.left, frame.top, frame.right + 1,                    frame.top + 2, paint);            canvas.drawRect(frame.left, frame.top + 2, frame.left + 2,                    frame.bottom - 1, paint);            canvas.drawRect(frame.right - 1, frame.top, frame.right + 1,                    frame.bottom - 1, paint);            canvas.drawRect(frame.left, frame.bottom - 1, frame.right + 1,                    frame.bottom + 1, paint);                         // Draw a red "laser scanner" line through the middle to show            // decoding is active             //鐢绘壂鎻忔涓嬮潰鐨勫瓧            paint.setColor(laserColor);            paint.setAlpha(SCANNER_ALPHA[scannerAlpha]);            scannerAlpha = (scannerAlpha + 1) % SCANNER_ALPHA.length;            int middle = count%frame.height()  + frame.top;            canvas.drawRect(frame.left + 2, middle - 1, frame.right - 1,                    middle + 2, paint);              count+=3;                     //画扫描框边上的角，总共8个部分               paint.setColor(Color.GREEN);                canvas.drawRect(frame.left, frame.top, frame.left + ScreenRate,                        frame.top + CORNER_WIDTH, paint);                canvas.drawRect(frame.left, frame.top, frame.left + CORNER_WIDTH, frame.top                        + ScreenRate, paint);                canvas.drawRect(frame.right - ScreenRate, frame.top, frame.right,                        frame.top + CORNER_WIDTH, paint);                canvas.drawRect(frame.right - CORNER_WIDTH, frame.top, frame.right, frame.top                        + ScreenRate, paint);                canvas.drawRect(frame.left, frame.bottom - CORNER_WIDTH, frame.left                        + ScreenRate, frame.bottom, paint);                canvas.drawRect(frame.left, frame.bottom - ScreenRate,                        frame.left + CORNER_WIDTH, frame.bottom, paint);                canvas.drawRect(frame.right - ScreenRate, frame.bottom - CORNER_WIDTH,                        frame.right, frame.bottom, paint);                canvas.drawRect(frame.right - CORNER_WIDTH, frame.bottom - ScreenRate,                        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.            //鍙埛鏂版壂鎻忔鐨勫唴瀹癸紝鍏朵粬鍦版柟涓嶅埛鏂�            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);    }}