android andbatdog电池监控

【核心代码】

/*******************************************************************************
 * Copyright (c) 2009 Ferenc Hechler - ferenc_hechler@users.sourceforge.net
 * 
 * This file is part of the Android Battery Dog
 *
 * The Android Battery Dog is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License as published by the Free Software Foundation;
 * either version 2 of the License, or (at your option) any later version.
 * 
 * The Android Battery Dog is distributed
 * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with the Android Battery Dog;
 * if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *  
 *******************************************************************************/
package net.sf.andbatdog.batterydog;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.util.ArrayList;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Bundle;
import android.os.Environment;
import android.view.Display;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;

public class BatteryGraph extends Activity {


	private final static String TAG = "BATDOG.graph";

	private final static int MENU_4H    = 1;
    private final static int MENU_8H    = 2;
    private final static int MENU_24H   = 3;
    private final static int MENU_3DAYS = 4;
    private final static int MENU_7DAYS = 5;
    private final static int MENU_ALL   = 6;
	
	private final static int margXLeft = 5;
	private final static int margXRight = 5;
	private final static int margYTop = 60;
	private final static int margYBottom = 5;
	
	private long width = 300;
	private long height = 300;
	private long w = width  - margXLeft - margXRight;
	private long h = height - margYTop  - margYBottom;

	private long msecPerHour = 1000*60*60;
	private long mDeltaTime = 24*msecPerHour;
	private long mOffset = 0;
	private GraphView mGraphView;
	
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mGraphView = new GraphView(this);
        setContentView(mGraphView);
    }

    /**
     * Called when your activity's options menu needs to be created.
     */
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        menu.add(Menu.NONE, MENU_4H,    Menu.NONE, "4h");
        menu.add(Menu.NONE, MENU_8H,    Menu.NONE, "8h");
        menu.add(Menu.NONE, MENU_24H,   Menu.NONE, "24h");
        menu.add(Menu.NONE, MENU_3DAYS, Menu.NONE, "3 days");
        menu.add(Menu.NONE, MENU_7DAYS, Menu.NONE, "7 days");
        menu.add(Menu.NONE, MENU_ALL,   Menu.NONE, "all");
        return true;
    }
    
    /**
     * Called when a menu item is selected.
     */
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
    	if (item.getItemId() == MENU_4H) {
    		mDeltaTime = 4*60*60*1000;
			mOffset = 0;
    		mGraphView.invalidate();
    	}
    	else if (item.getItemId() == MENU_8H) {
    		mDeltaTime = 8*60*60*1000;
			mOffset = 0;
    		mGraphView.invalidate();
    	}
    	else if (item.getItemId() == MENU_24H) {
    		mDeltaTime = 24*60*60*1000;
			mOffset = 0;
    		mGraphView.invalidate();
    	}
    	else if (item.getItemId() == MENU_3DAYS) {
    		mDeltaTime = 3*24*60*60*1000;
			mOffset = 0;
    		mGraphView.invalidate();
    	}
    	else if (item.getItemId() == MENU_7DAYS) {
    		mDeltaTime = 7*24*60*60*1000;
			mOffset = 0;
    		mGraphView.invalidate();
    	}
    	else if (item.getItemId() == MENU_ALL) {
    		mDeltaTime = 0;
			mOffset = 0;
    		mGraphView.invalidate();
    	}
        mGraphView.readRecords(); // update from service
        return true;
    }
    
    @Override
    public boolean onTrackballEvent(MotionEvent event) {
    	super.onTrackballEvent(event);
    	if (event.getAction() == MotionEvent.ACTION_DOWN) {
    		mOffset = 0;
            mGraphView.readRecords(); // update from service
			mGraphView.invalidate();
    	}
    	else if (event.getAction() == MotionEvent.ACTION_MOVE) {
    		float x = event.getRawX();
    		if (x < 0) {
    			mOffset -= mDeltaTime/5;
    			mGraphView.invalidate();
    		} 
    		else if (x>0) {
    			mOffset  = mDeltaTime/5;
    			if (mOffset > 0)
    				mOffset = 0;
    			mGraphView.invalidate();
    		}
    	}
    	return true;
    }
    
    
    private class GraphView extends View {
        private Paint   mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    	private BatteryRecord[] mRecords;
    	private float mLastX;
        
        public void readRecords() {
        	try {
        		mRecords = readLog();
        	}
        	catch (Exception e) {
        		Log.e(TAG,e.getMessage(), e);
			}
        }

        @Override
        public boolean onTouchEvent(MotionEvent event) {
        	super.onTouchEvent(event);
        	if (event.getAction() == MotionEvent.ACTION_DOWN) {
        		mLastX = event.getRawX();
        	}
        	else if (event.getAction() == MotionEvent.ACTION_MOVE) {

//        		Log.i(TAG, event.toString() " - "   event.getHistorySize());
        		float x = event.getRawX();
        		float dx = x-mLastX;
        		mLastX = x;
        		long ldx = (long)(mDeltaTime*dx/width);
        		mOffset -= ldx;
    			if (mOffset > 0)
    				mOffset = 0;
    			mGraphView.invalidate();
        	}
        	return true;
        }
        
        public GraphView(Context context) {
            super(context);
            readRecords();

            Display display = ((WindowManager) context.getSystemService(WINDOW_SERVICE)).getDefaultDisplay();
            width = display.getWidth();  
            height = display.getHeight();
        	w = width - margXLeft - margXRight;
        	h = height - margYTop - margYBottom;
        }
        
		@Override protected void onDraw(Canvas canvas) {
			Paint paint = mPaint;
            paint.setStrokeWidth(1);

			Paint paintP = new Paint(Paint.ANTI_ALIAS_FLAG);
            paintP.setStrokeWidth(2);
            paintP.setColor(Color.YELLOW);
			Paint paintV = new Paint();
            paintV.setStrokeWidth(0);
            paintV.setColor(Color.RED);
			Paint paintT = new Paint();
            paintT.setStrokeWidth(0);
            paintT.setColor(Color.GREEN);
			Paint paintD = new Paint(); // discharge rate
            paintD.setStrokeWidth(0);
            paintD.setColor(Color.CYAN);
            
			canvas.drawColor(Color.BLACK);

            if ((mRecords == null) || (mRecords.length == 0)) {
                paint.setColor(Color.WHITE);
                canvas.drawText("no data found", 10, 50, paint);
                return;
            }
            
            drawMarker(canvas, paintP, paintV, paintT, paintD);
            
            int maxRec = mRecords.length;
            long minTime = mRecords[0].timestamp;
            long maxTime = mRecords[maxRec-1].timestamp;
            long dTime = maxTime-minTime;
            if (mDeltaTime != 0) {
            	// make minTime, maxTime be min and max time on screen
            	dTime = mDeltaTime;
            	minTime = maxTime-dTime mOffset;
            	maxTime = minTime mDeltaTime;
            }
            
        	BatteryRecord rec;
        	BatteryRecord oldRec;
			for (int i = 0; i <= maxRec; i  ) {
            	if (i == 0)
            		oldRec = mRecords[0];
            	else
            		oldRec = mRecords[i-1];
            	if (i == maxRec)
            		rec = mRecords[maxRec-1];
            	else
            		rec = mRecords[i];

            	if (rec.timestamp >= minTime && oldRec.timestamp <= maxTime) // clip to screen
            		drawRecordLine(canvas, rec, oldRec, minTime, dTime, paintP, paintV, paintT);
			}
			drawDischargeRateGraph(canvas, minTime, maxTime, paintD);
        }

		private void drawMarker(Canvas canvas, Paint paintP, Paint paintV, Paint paintT, Paint paintD) {
			Paint paint = new Paint();
            for (int i = 0; i <= 10; i  ) {
            	if (i == 5)
                    paint.setColor(Color.GRAY);
            	else
                    paint.setColor(Color.DKGRAY);
            	float x = margXLeft;
            	float y = margYBottom h*(10-i)/10;
            	canvas.drawLine(x, y, x w, y, paint);
			}
        	canvas.drawText("100%", margXLeft, margYBottom 13, paintP);
        	canvas.drawText("4V", margXLeft, margYBottom h*6/10 13, paintV);
        	canvas.drawText("30?, margXLeft, margYBottom h*7/10 13, paintT);
        	canvas.drawText("10%/hr", margXLeft, margYBottom h*9/10 13, paintD);

        	canvas.drawText("100%", margXLeft w-26, margYBottom 13, paintP);
        	canvas.drawText("4V", margXLeft w-20, margYBottom h*6/10 13, paintV);
        	canvas.drawText("30?, margXLeft w-20, margYBottom h*7/10 13, paintT);
        	canvas.drawText("2V", margXLeft w-20, margYBottom h*10/10, paintV);
        	canvas.drawText("10%/hr", margXLeft w-45, margYBottom h*9/10 13, paintD);
		}

		private void drawRecordLine(Canvas canvas, 
				BatteryRecord rec, BatteryRecord oldRec,
				long minTime, long dTime,
				Paint paintP, Paint paintV, Paint paintT
				) {

			float x1 = margXLeft (w*(oldRec.timestamp-minTime)) / dTime; 
			float yP1 = margYBottom h-(h*oldRec.level) / rec.scale; 
			float yV1 = margYBottom h-(h*2*(oldRec.voltage-2000)) / 10000; 
			float yT1 = margYBottom h-(h*oldRec.temperature) / 1000; 
			float x2 = margXLeft (w*(   rec.timestamp-minTime)) / dTime; 
			float yP2 = margYBottom h-(h*rec.level) / rec.scale;
			float yV2 = margYBottom h-(h*2*(rec.voltage-2000)) / 10000;
			float yT2 = margYBottom h-(h*rec.temperature) / 1000;
			
			if (x1 < 0) { 
				// clip to left edge; very large -ve X values cause gfx probs on Android.
				// Maybe it's using shorts internally somewhere.
				float dx_frac=(-x1)/(x2-x1);
				yP1 = (yP2-yP1)*dx_frac yP1;
				yV1 = (yV2-yV1)*dx_frac yV1;
				yT1 = (yT2-yT1)*dx_frac yT1;
				x1 = 0;
			}
			canvas.drawLine(x1, yP1, x2, yP2, paintP);
			canvas.drawLine(x1, yV1, x2, yV2, paintV);
			canvas.drawLine(x1, yT1, x2, yT2, paintT);
		}

		private void drawDischargeRateGraph(Canvas canvas, long minTime, long maxTime, Paint paint) {
			int nSteps = (int)width/2; // save time by not drawing every single point
			long timeSpan = maxTime-minTime;
			long dTime = timeSpan/60; // time to integrate charge over.  Increase constant for smoother graph, decrease for more detail.
			long timeStep = timeSpan/nSteps;
			float chargeScale = mRecords[0].scale;
			BatteryRecordCursor now = new BatteryRecordCursor(mRecords);
			BatteryRecordCursor prev = new BatteryRecordCursor(mRecords);
			float x1 = margXLeft;
			float y1 = margYBottom; 
			for (int i = 0; i < nSteps; i  ) {
				long t = minTime   timeStep * i;
				now.moveToTime(t);
				prev.moveToTime(t-dTime);
				float chargeNow = now.getCharge();
				float chargePrev = prev.getCharge();
				// dCharge is discharge rate in percent per hour
				float dCharge = -(chargeNow-chargePrev) / dTime * msecPerHour;
				float x2 = margXLeft (w*(t-minTime)) / timeSpan; 
				float y2 = margYBottom h-(h*dCharge) / chargeScale; 
				if (i>0)
					canvas.drawLine(x1, y1, x2, y2, paint);
				x1 = x2;
				y1 = y2;
			}
		}
    }

//    class BatRecCache {
//    	float x;
//    	float yP;
//    	float yV;
//    	float yT;
//    	public BatRecCache(BatteryRecord rec) {
//    	}
//    }
//    
    class BatteryRecord {
		int count;
    	long timestamp;
    	int level;
    	int scale;
    	int voltage;
    	int temperature;
    	public BatteryRecord(int count, long timestamp, int level, int scale, int voltage, int temperature) {
    		this.count = count;
    		this.timestamp = timestamp;
    		this.level = level;
    		this.scale = scale;
    		this.voltage = voltage;
    		this.temperature = temperature;
    		
		}
    }
    
	static long lastRecordFileModtime = -1;
	static BatteryRecord[] lastLog;
    private BatteryRecord[] readLog() throws Exception {
    	ArrayList<BatteryRecord> result = new ArrayList<BatteryRecord>();
		File root = Environment.getExternalStorageDirectory();
		if (root == null)
	    	throw new Exception("external storage dir not found");
		File batteryLogFile = new File(root,BatteryDog_Service.LOGFILEPATH);
		if (!batteryLogFile.exists())
			throw new Exception("logfile '" batteryLogFile "' not found");
		if (!batteryLogFile.canRead())
			throw new Exception("logfile '" batteryLogFile "' not readable");
		long modtime = batteryLogFile.lastModified();
		if (modtime == lastRecordFileModtime)
			return lastLog;
		// file exists, is readable, and is recently modified -- reread it.
		lastRecordFileModtime = modtime;
		FileReader reader = new FileReader(batteryLogFile);
		BufferedReader in = new BufferedReader(reader);
		long currentTime = -1;
		String line = in.readLine();
		while (line != null) {
			BatteryRecord rec = parseLine(line);
			if (rec == null)
				Log.e(TAG, "could not parse line: '" line "'");
			else if (rec.timestamp < currentTime)
				Log.e(TAG, "ignoring '" line "' since it's older than prev log line");
			else {
				result.add(rec);
				currentTime = rec.timestamp;
			}
			line = in.readLine();
		}
		in.close();
		lastLog = (BatteryRecord[]) result.toArray(new BatteryRecord[result.size()]);
		return lastLog;
    }

	private BatteryRecord parseLine(String line) {
		if (line == null)
			return null;
		String[] split = line.split("[;]");
		if (split.length < 6)
			return null;
		if (split[0].equals("Nr"))
			return null;
		try {
			int count = Integer.parseInt(split[0]);
			long timestamp = Long.parseLong(split[1]);
			int level = Integer.parseInt(split[2]);
			int scale = Integer.parseInt(split[3]);
			int voltage = Integer.parseInt(split[4]);
			int temperature = Integer.parseInt(split[5]);
			return new BatteryRecord(count, timestamp, level, scale, voltage, temperature);
		}
		catch (Exception e) {
			Log.e(TAG,"Invalid format in line '" line "'");
			return null;
		}
	}
    
	// BatteryRecordCursor allows looking up the charge level 
	// at any point in time, and quickly finding the charge at 
	// a later time (incrementally)
	class BatteryRecordCursor {
		long currentTime;
		int currentRec;
		BatteryRecord[] records;

		public BatteryRecordCursor(BatteryRecord[] records) {
			// preset to latest time
			this.records = records;
			currentRec = records.length-1;
			currentTime = records[currentRec].timestamp;
		}
		float getCharge() {
			// get the charge at the currentTime (assumes currentRec is set correctly)
			BatteryRecord r0 = records[currentRec];
			BatteryRecord r1 = records[currentRec >= records.length ? currentRec : currentRec 1];
			long t0 = r0.timestamp;
			long t1 = r1.timestamp;
			float c0 = r0.level;
			float c1 = r1.level;
			return c0   (c1 - c0)*((currentTime-t0)/(float)(t1-t0));
		}
		void setTime(long t) {
			// find the record containing t (the latest with timestamp <= t)
			// This is slow, linear search from the end.
			currentRec = 0;
			currentTime = records[0].timestamp;
			for (int i = records.length-1; i > 0; i--) {
				if (records[i].timestamp <= t) {
					currentRec = i;
					currentTime = t;
					break;
				}
			}
		}
		float moveToTime(long t) {
			// Move from the current time to new time t.
			// If t is ahead of current time but not by much, this is fast.
			if (t < currentTime) { 
				// moving backward: this is slow
				setTime(t);
				return getCharge();
			}
			else {
				// moving forward; search from current location
				// This is the intended use.
				while (currentRec < records.length - 1 && records[currentRec 1].timestamp <= t) {
					currentRec  ;
				}
				currentTime = t;
				return getCharge();
			}
		}
	}

}