package com.example.change1;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.RandomAccessFile;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Activity;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Menu;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
public class MainActivity extends Activity {
/** Called when the activity is first created. */
Button btnSimpleDraw, btnTimerDraw;
SurfaceView sfv;
SurfaceHolder sfh;
private Timer mTimer;
private MyTimerTask mTimerTask;
int Y_axis[],//保存Y轴上的点
centerY,//中心线
oldX,oldY,//上一个XY点
currentX;//当前绘制到的X轴上的点
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnSimpleDraw = (Button) this.findViewById(R.id.drawbotton);
btnTimerDraw = (Button) this.findViewById(R.id.timerbotton);
btnSimpleDraw.setOnClickListener(new ClickEvent());
btnTimerDraw.setOnClickListener(new ClickEvent());
sfv = (SurfaceView) this.findViewById(R.id.surfaceview);
sfh = sfv.getHolder();
//动态绘制
mTimer = new Timer();
mTimerTask = new MyTimerTask();
String string = "";
String mString = null;
//File file = new File("/mnt/sdcard/abc.txt");//读取txt中数据
try {
FileInputStream fis=new FileInputStream(Environment.getExternalStorageDirectory()+"/abc.txt");
byte buffer[]=new byte[1024];
ByteArrayOutputStream baops=new ByteArrayOutputStream();
int length=0;
try {
while((length=fis.read(buffer))!=-1){
baops.write(buffer, 0, length);
string=baops.toString();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (FileNotFoundException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
//RandomAccessFile randomAccessFile = null;
// try {
//
// //randomAccessFile = new RandomAccessFile(file,"rw");
// } catch (FileNotFoundException e) {
// // TODO 自动生成的 catch 块
// e.printStackTrace();
// }
// try {
// while((mString=randomAccessFile.readLine())!= null) ;
//
// System.out.println(mString+"只拿去了");
// string += mString;
// } catch (Exception e) {
// // TODO: handle exception
// }
String[] strings = string.split(",");
int[] array = new int[strings.length];
for(int i=0;i<array.length;i++){
if(strings[i]=="" || strings[i].equals("")){
}else{
array[i] = Integer.valueOf(strings[i]);
}
}
// 初始化y轴数据
centerY = (getWindowManager().getDefaultDisplay().getHeight() - sfv
.getTop()) / 2;
Y_axis = new int[getWindowManager().getDefaultDisplay().getWidth()];
for (int i = 1; i < Y_axis.length; i++) {// array中的数据复制给Y_axis
Y_axis[i-1] = array[i];
}
}
class ClickEvent implements View.OnClickListener { //点击事件
@Override
public void onClick(View v) {
if (v == btnSimpleDraw) {
SimpleDraw(Y_axis.length-1);//直接绘制
} else if (v == btnTimerDraw) {
oldY = centerY;
mTimer.schedule(mTimerTask, 0, 5);//动态绘制
}
}
}
class MyTimerTask extends TimerTask {
@Override
public void run() {
SimpleDraw(currentX);
currentX++;//往前进
if (currentX == Y_axis.length - 1) {//如果到了终点,则清屏重来
ClearDraw();
currentX = 0;
oldY = centerY;
}
}
}
/*
* 绘制指定区域
*/
void SimpleDraw(int length) {
if (length == 0)
oldX = 0;
Canvas canvas = sfh.lockCanvas(new Rect(oldX, 0, oldX + length,
getWindowManager().getDefaultDisplay().getHeight()));// 关键:获取画布
Log.i("Canvas:",
String.valueOf(oldX) + "," + String.valueOf(oldX + length));
Paint mPaint = new Paint();
mPaint.setColor(Color.GREEN);// 画笔为绿色
mPaint.setStrokeWidth(2);// 设置画笔粗细
int y;
for (int i = oldX + 1; i < length; i++) {// 绘画正弦波
y = Y_axis[i - 1];
canvas.drawLine(oldX, oldY, i, y, mPaint);
oldX = i;
oldY = y;
}
sfh.unlockCanvasAndPost(canvas);// 解锁画布,提交画好的图像
}
void ClearDraw() {
Canvas canvas = sfh.lockCanvas(null);
canvas.drawColor(Color.BLACK);// 清除画布
sfh.unlockCanvasAndPost(canvas);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}