cameraButton.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View v) {
  Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
  startActivityForResult(intent,TAKE_PHOTO);
 }
});

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 super.onActivityResult(requestCode, resultCode, data);
 if(resultCode==RESULT_OK){
  Bundle bundle=data.getExtras();
  Bitmap bitmap=(Bitmap)bundle.get("data");
  photoImageView.setImageBitmap(bitmap);
 }
}

 /**
  * 自定义图片名，获取照片的file
  */
 private File createImgFile(){
  //确定文件名
  String fileName="img_"+new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date())+".jpg";
//  File dir=getExternalFilesDir(Environment.DIRECTORY_PICTURES);
//  File dir=Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
//  File dir=Environment.getExternalStorageDirectory();
  File dir;
  if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
   dir=Environment.getExternalStorageDirectory();
  }else{
   dir=getExternalFilesDir(Environment.DIRECTORY_PICTURES);
  }
  File tempFile=new File(dir,fileName);
  try{
   if(tempFile.exists()){
    tempFile.delete();
   }
   tempFile.createNewFile();
  }catch (IOException e){
   e.printStackTrace();
  }
  //获取文件路径
  photoPath=tempFile.getAbsolutePath();
  return tempFile;
 }
 
 //拍照
 cameraButton.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View view) {
   //只是加了一个uri作为地址传入
   Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
   File photoFile=createImgFile();
   photoUri=Uri.fromFile(photoFile);
   intent.putExtra(MediaStore.EXTRA_OUTPUT,photoUri);
   startActivityForResult(intent,TAKE_PHOTO);
  }
 });

 /**
  * 压缩图片
  */
 private void setImageBitmap(){
  //获取imageview的宽和高
  int targetWidth=photoImageView.getWidth();
  int targetHeight=photoImageView.getHeight();

  //根据图片路径，获取bitmap的宽和高
  BitmapFactory.Options options=new BitmapFactory.Options();
  options.inJustDecodeBounds=true;
  BitmapFactory.decodeFile(photoPath,options);
  int photoWidth=options.outWidth;
  int photoHeight=options.outHeight;

  //获取缩放比例
  int inSampleSize=1;
  if(photoWidth>targetWidth||photoHeight>targetHeight){
   int widthRatio=Math.round((float)photoWidth/targetWidth);
   int heightRatio=Math.round((float)photoHeight/targetHeight);
   inSampleSize=Math.min(widthRatio,heightRatio);
  }

  //使用现在的options获取Bitmap
  options.inSampleSize=inSampleSize;
  options.inJustDecodeBounds=false;
  Bitmap bitmap=BitmapFactory.decodeFile(photoPath,options);
  photoImageView.setImageBitmap(bitmap);
 }

 //将图片添加进手机相册
 private void galleryAddPic(){
  Intent mediaScanIntent=new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
  mediaScanIntent.setData(photoUri);
  this.sendBroadcast(mediaScanIntent);
 }

 //从相册获取照片
 albumButton.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View view) {
   //Intent intent=new Intent(Intent.ACTION_PICK);
   Intent intent=new Intent(Intent.ACTION_GET_CONTENT);
   intent.setType("image/*");
   startActivityForResult(intent,PICK_PHOTO);
  }
 });
 
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
  super.onActivityResult(requestCode, resultCode, data);
  if(resultCode==RESULT_OK){
   switch (requestCode){
    case TAKE_PHOTO:
     setImageBitmap();
     galleryAddPic();
     break;
    case PICK_PHOTO:
     //data中自带有返回的uri
     photoUri=data.getData();
     //获取照片路径
     String[] filePathColumn={MediaStore.Audio.Media.DATA};
     Cursor cursor=getContentResolver().query(photoUri,filePathColumn,null,null,null);
     cursor.moveToFirst();
     photoPath=cursor.getString(cursor.getColumnIndex(filePathColumn[0]));
     cursor.close();
     //有了照片路径，之后就是压缩图片，和之前没有什么区别
     setImageBitmap();
     break;
   }
  }
 }