android调用系统照相机返回到页面，保存到本地和把图片转换成字符串

本程序能通过调用android自带的照相机，返回图片到imageview上，并能读取内存卡保存到内存卡上，还能把该图片转换成字符串，以便能上传到服务器。
需要用到的架包是commons-codec-1.5.jar。
<--layout布局-->

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#FFD3D7DF" >

    <LinearLayout
        android:id="@+id/takePicturePhone"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_marginBottom="10dip"
        android:layout_marginLeft="10dip"
        android:layout_marginRight="10dip"
        android:layout_marginTop="10dip"
        android:background="@drawable/bg_frame"
        android:gravity="center_vertical"
        android:orientation="vertical"
        android:paddingBottom="2dip"
        android:paddingLeft="10dip"
        android:paddingRight="10dip"
        android:paddingTop="10dip" >

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" >

            <ImageButton
                android:id="@+id/takePhone"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:src="@drawable/takepicture" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="154dp" >

            <ImageView
                android:id="@+id/preview"
                android:layout_width="wrap_content"
                android:layout_height="92dp" />
        </LinearLayout>
    </LinearLayout>

</LinearLayout>

<--activity-->

package zhang.xue.yi;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.apache.commons.codec.binary.Base64;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.Toast;

/**
 * 拍照
 * 
 * @author Mr.Z
 * @time 2012-5-16
 * 
 */
public class TakePhotoActivity extends Activity {
	private Context context = TakePhotoActivity.this;

	private ImageButton btnTakePhone;
	private String path;
	private ImageView imageView;
	private Bitmap[] bmps = new Bitmap[6];
	private Bundle bundle;

	private LinearLayout takePicturePhone = null;

	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		this.setContentView(R.layout.locationapp);

		takePicturePhone = (LinearLayout) findViewById(R.id.takePicturePhone);
		useTakePicture();

	}

	/**
	 * 照相信息采集
	 */
	private void useTakePicture() {
		imageView = (ImageView) this.findViewById(R.id.preview);
		btnTakePhone = (ImageButton) findViewById(R.id.takePhone);
		btnTakePhone.setOnTouchListener(new OnTouchListener() {

			@Override
			public boolean onTouch(View v, MotionEvent event) {
				if (event.getAction() == MotionEvent.ACTION_DOWN) {
					// 更改为按下时的背景图片
					bmps[0] = BitmapFactory.decodeResource(getResources(), R.drawable.takepicture2);
					btnTakePhone.setImageBitmap(bmps[0]);
				} else if (event.getAction() == MotionEvent.ACTION_UP) {
					// 改为抬起时的图片
					bmps[1] = BitmapFactory.decodeResource(getResources(), R.drawable.takepicture);
					btnTakePhone.setImageBitmap(bmps[1]);
				}
				return false;
			}
		});
		btnTakePhone.setOnClickListener(new Button.OnClickListener() {
			public void onClick(View arg0) {
				Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
				startActivityForResult(intent, 1);
			}
		});
	}

	/**
	 *回显系统照片
	 */
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		super.onActivityResult(requestCode, resultCode, data);
		if (resultCode == Activity.RESULT_OK) {
			String sdStatus = Environment.getExternalStorageState();
			if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用
				Toast.makeText(context, "SD卡不存在！", 1000);
				return;
			}
			bundle = data.getExtras();
			Bitmap bitmap = (Bitmap) bundle.get("data");// 获取相机返回的数据，并转换为Bitmap图片格式
			FileOutputStream b = null;
			File file = new File("/sdcard/channel/");
			file.mkdirs();// 创建文件夹
			path = "/sdcard/channel/" + formatDatetime(new Date(), "yyyyMMddHHmmss") + ".jpg";
			try {
				System.out.println("path：" + path);
				b = new FileOutputStream(path);
				bitmap.compress(Bitmap.CompressFormat.JPEG, 100, b);// 把数据写入文件
				getImageBinary();
			} catch (FileNotFoundException e) {
				e.printStackTrace();
			} finally {
				try {
					b.flush();
					b.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			this.imageView.setImageBitmap(bitmap);// 将图片显示在ImageView里
		}
	}

	/**
	 * 图片转换成字符串[BASE64]
	 * 
	 * @return
	 */
	public String getImageBinary() {
		System.out.println("path--->" + path);
		try {
			FileInputStream fis = new FileInputStream(path);
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			byte[] buffer = new byte[8192];
			int count = 0;
			while ((count = fis.read(buffer)) >= 0) {
				baos.write(buffer, 0, count);

			}
			String uploadBuffer = new String(Base64.encodeBase64(baos.toByteArray()));
			fis.close();
			System.out.println("图片信息转换成字符串为：---->" + uploadBuffer);
			return uploadBuffer;
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		return null;
	}

	/**
	 * 根据指定的日期格式生成日期时间串
	 * 
	 * @param format 日期格式,如yyyyMMdd
	 * @return dateTimeString
	 */
	public static String formatDatetime(Date date, String format) {
		DateFormat df = new SimpleDateFormat(format);
		return df.format(date);
	}
}

<--权限-->

    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />