it.jaschke.alexandria.BarcodeTrackerFactory.java Source code

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/*
 * Copyright (C) The Android Open Source Project
 *
 * 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 it.jaschke.alexandria;

import android.content.Context;
import android.content.Intent;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.support.v4.content.LocalBroadcastManager;

import it.jaschke.alexandria.CameraPreview.GraphicOverlay;
import com.google.android.gms.vision.MultiProcessor;
import com.google.android.gms.vision.Tracker;
import com.google.android.gms.vision.barcode.Barcode;

/**
 * Factory for creating a tracker and associated graphic to be associated with a new barcode.  The
 * multi-processor uses this factory to create barcode trackers as needed -- one for each barcode.
 */
class BarcodeTrackerFactory implements MultiProcessor.Factory<Barcode> {

    private GraphicOverlay mGraphicOverlay;
    private Context mContext;

    BarcodeTrackerFactory(GraphicOverlay graphicOverlay, Context ctx) {

        mGraphicOverlay = graphicOverlay;
        mContext = ctx;
    }

    @Override
    public Tracker<Barcode> create(Barcode barcode) {
        BarcodeGraphic graphic = new BarcodeGraphic(mGraphicOverlay, mContext);
        return new GraphicTracker<>(mGraphicOverlay, graphic);
    }

}

/**
 * Graphic instance for rendering barcode position, size, and ID within an associated graphic
 * overlay view.
 */
class BarcodeGraphic extends TrackedGraphic<Barcode> {
    private static final int COLOR_CHOICES[] = { Color.BLUE, Color.CYAN, Color.GREEN };
    private static int mCurrentColorIndex = 0;

    private Paint mRectPaint;
    private Paint mTextPaint;
    private volatile Barcode mBarcode;
    private Context mContext;

    BarcodeGraphic(GraphicOverlay overlay, Context ctx) {
        super(overlay);

        mContext = ctx;
        mCurrentColorIndex = (mCurrentColorIndex + 1) % COLOR_CHOICES.length;
        final int selectedColor = COLOR_CHOICES[mCurrentColorIndex];

        mRectPaint = new Paint();
        mRectPaint.setColor(selectedColor);
        mRectPaint.setStyle(Paint.Style.STROKE);
        mRectPaint.setStrokeWidth(4.0f);

        mTextPaint = new Paint();
        mTextPaint.setColor(selectedColor);
        mTextPaint.setTextSize(80.0f);
    }

    /**
     * Updates the barcode instance from the detection of the most recent frame.  Invalidates the
     * relevant portions of the overlay to trigger a redraw.
     */
    void updateItem(Barcode barcode) {
        mBarcode = barcode;
        postInvalidate();
    }

    /**
     * Draws the barcode annotations for position, size, and raw value on the supplied canvas.
     */
    @Override
    public void draw(Canvas canvas) {
        Barcode barcode = mBarcode;
        if (barcode == null) {
            return;
        }

        // Draws the bounding box around the barcode.
        RectF rect = new RectF(barcode.getBoundingBox());
        rect.left = translateX(rect.left);
        //rect.top = translateY(rect.top);
        //rect.right = translateX(rect.right);
        rect.bottom = translateY(rect.bottom);
        //canvas.drawRect(rect, mRectPaint);

        // Draws a label at the bottom of the barcode indicate the barcode value that was detected.
        canvas.drawText(barcode.rawValue, rect.left, rect.bottom, mTextPaint);

        sendMessage(barcode.rawValue);
    }

    private void sendMessage(String s) {
        Intent intent = new Intent("BarcodeDetected");
        // add data
        intent.putExtra("RawValue", s);
        LocalBroadcastManager.getInstance(mContext).sendBroadcast(intent);
    }
}