android拍照并保存图片至sdcard例子_

package com.example.photograph;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
 
 

import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.text.TextUtils;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener{

	
	Button finish,agin,savebtn;
	  ImageView photoshow;
    RelativeLayout takephoto,imageshowlayout;
	 private Button Camerabtn;
	 EditText editname;
	 Bitmap bitmap,mBitmap;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		editname=(EditText) findViewById(R.id.editname);
		Camerabtn=(Button) findViewById(R.id.Camerabtn);
		  finish=(Button) findViewById(R.id.finish);
		  agin=(Button) findViewById(R.id.agin);
		  savebtn=(Button) findViewById(R.id.savebtn);
		  photoshow=(ImageView) findViewById(R.id.photoshow);
		  takephoto=(RelativeLayout) findViewById(R.id.takephoto);
		  imageshowlayout=(RelativeLayout) findViewById(R.id.imageshowlayout);
		Camerabtn.setOnClickListener(this);
		agin.setOnClickListener(this);
		savebtn.setOnClickListener(this);
		finish.setOnClickListener(this);
		
	}


	@Override
	public void onClick(View v) {
		// TODO Auto-generated method stub
		Intent cameraIntent=null;
		Uri imageUri=null;
		switch (v.getId()) {
		case R.id.Camerabtn:
//		  Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
//			startActivityForResult(intent, 1);
		 cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
			 imageUri = Uri.fromFile(new File(Environment.getExternalStorageDirectory(),"workupload.jpg")); 
			//指定照片保存路径（SD卡），workupload.jpg为一个临时文件，每次拍照后这个图片都会被替换 
			cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
			startActivityForResult(cameraIntent, 1);
			break;
		case R.id.finish:
			takephoto.setVisibility(View.VISIBLE);
			imageshowlayout.setVisibility(View.GONE);
			break;
		case R.id.agin:
		  cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
			 imageUri = Uri.fromFile(new File(Environment.getExternalStorageDirectory(),"workupload.jpg")); 
			//指定照片保存路径（SD卡），workupload.jpg为一个临时文件，每次拍照后这个图片都会被替换 
			cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
			startActivityForResult(cameraIntent, 1);
			break;
		case R.id.savebtn:
			 String imagename=editname.getText().toString().trim();
			 if(TextUtils.isEmpty(imagename)){
				 Toast.makeText(MainActivity.this, "请输入照片名称", Toast.LENGTH_LONG).show();
			  return;
			 }
			 String sdStatus = Environment.getExternalStorageState();
				if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用
					Log.v("TestFile",
							"SD card is not avaiable/writeable right now.");
					return;
				}
			FileOutputStream b = null;
			String filename=getResources().getString(R.string.filename);
			File file = new File(filename);
			file.mkdirs();// 创建文件夹
			String fileName = filename imagename ".png";

			try {
				b = new FileOutputStream(fileName);
				bitmap.compress(Bitmap.CompressFormat.PNG, 100, b);// 把数据写入文件
			} catch (FileNotFoundException e) {
				e.printStackTrace();
			} finally {
				try {
					b.flush();
					b.close();
				} catch (IOException e) {
					e.printStackTrace();
				}
				Toast.makeText(MainActivity.this, "照片保存成功", Toast.LENGTH_LONG).show();
			}
		 
		  break;
		}
		
 

		}
	
	
	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		super.onActivityResult(requestCode, resultCode, data);

		if (resultCode == Activity.RESULT_OK) {
			takephoto.setVisibility(View.GONE);
			imageshowlayout.setVisibility(View.VISIBLE);
	 Bitmap camorabitmap = BitmapFactory.decodeFile(Environment.getExternalStorageDirectory() "/workupload.jpg"); 
	 if(null != camorabitmap ){
     // 下面这两句是对图片按照一定的比例缩放，这样就可以完美地显示出来。
     int scale = ImageThumbnail.reckonThumbnail(camorabitmap.getWidth(),camorabitmap.getHeight(), 500, 600);  
     bitmap = ImageThumbnail.PicZoom(camorabitmap, camorabitmap.getWidth() / scale,camorabitmap.getHeight() / scale); 
     //由于Bitmap内存占用较大，这里需要回收内存，否则会报out of memory异常 
     camorabitmap.recycle(); 
    //将处理过的图片显示在界面上  
    photoshow.setImageBitmap(bitmap);  
 
    }

		}
	}
		
  @Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
	// TODO Auto-generated method stub
	  if (keyCode == KeyEvent.KEYCODE_BACK) { // 监控/拦截/屏蔽返回键
			if (imageshowlayout.getVisibility() == View.VISIBLE) {
				imageshowlayout.setVisibility(View.GONE);
				takephoto.setVisibility(View.VISIBLE);
			} else {
				finish();
			}
			return false;
		}
	  
	return super.onKeyDown(keyCode, event);
}
	 
	
	}