代码片段

package com.tang.paint;import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.media.MediaScannerConnection;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.Toast;
import android.os.Build;public class MainActivity extends Activity {private ImageView iv;private Bitmap basemap;private Canvas canvas;private Paint paint;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);iv = (ImageView) findViewById(R.id.pic);paint = new Paint();paint.setStrokeWidth(5);paint.setColor(Color.GREEN);basemap = Bitmap.createBitmap(768, 1100, Bitmap.Config.ARGB_8888);canvas = new Canvas(basemap);canvas.drawColor(Color.WHITE); //设置颜色iv.setOnTouchListener(new OnTouchListener() {int startX;int startY;public boolean onTouch(View view, MotionEvent event) {switch (event.getAction()) {case MotionEvent.ACTION_DOWN: //下笔startX = (int) event.getX();startY = (int) event.getY();break;case MotionEvent.ACTION_MOVE: //移动int newX = (int) event.getX();int newY = (int) event.getY();canvas.drawLine(startX, startY, newX, newY, paint);startX = (int) event.getX();startY = (int) event.getY();iv.setImageBitmap(basemap);break;case MotionEvent.ACTION_UP: //抬笔break;}return true;}});}public void save(View view){System.out.println(Environment.getDataDirectory());System.out.println(Environment.getExternalStorageDirectory());try {String fileName = System.currentTimeMillis()+".jpg";File file = new File(Environment.getExternalStorageDirectory(), fileName);FileOutputStream stream;stream = new FileOutputStream(file);basemap.compress(CompressFormat.JPEG, 100, stream);//通知相册//Intent intent = new Intent(Intent.ACTION_MEDIA_MOUNTED);//intent.setData(Uri.fromFile(Environment.getExternalStorageDirectory()));//sendBroadcast(intent);//4.4以后MediaScannerConnection.scanFile(this, new String[]{Environment.getExternalStorageDirectory()+"/" + fileName}, null, null);Toast.makeText(this, "保存成功", Toast.LENGTH_SHORT).show();} catch (Exception e) {// TODO Auto-generated catch blockToast.makeText(this, "保存失败", Toast.LENGTH_SHORT).show();e.printStackTrace();}}
}