Android开发实现ImageView加载摄像头拍摄的大图功能
来源：爱站网时间：2020-05-06编辑：网友分享
Android开发中拍照功能是最基本的功能之一，我们要实现ImageView加载摄像头拍摄的大图功能，首先要快速调用系统相机，而后对图片进行裁剪，才能显示在我们需要的界面，快进入下文学习爱站技术频道的介绍吧！
Android开发中拍照功能是最基本的功能之一，我们要实现ImageView加载摄像头拍摄的大图功能，首先要快速调用系统相机，而后对图片进行裁剪，才能显示在我们需要的界面，快进入下文学习爱站技术频道的介绍吧！
权限
另：关于权限控制还可参考：Android Manifest功能与权限描述大全
设置变量保存文件存储路径
private String mCurrentPhotoPath; /** * 拍照flag */ private static final int REQUEST_IMAGE_CAPTURE_O = 2;
创建存储路径及文件名
/**
* 创建拍摄的图片的存储路径及文件名
* @return
* @throws IOException
*/
private File createImageFile() throws IOException{
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "JPEG_" + timeStamp + "_";
File storageDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
Log.d("TrainingFirstActivity", "storageDir:" + storageDir);
File image = File.createTempFile(imageFileName, ".jpg", storageDir);
mCurrentPhotoPath = image.getAbsolutePath();
Log.d("image.getAbsolutePath()", image.getAbsolutePath() + "");
return image;
}
拍摄图片并保存
Intent takePictureOintent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (takePictureOintent.resolveActivity(getPackageManager()) != null){
File photoFile = null;
try {
photoFile = createImageFile();
} catch (IOException e) {
e.printStackTrace();
}
if (photoFile != null){
takePictureOintent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile));
startActivityForResult(takePictureOintent, REQUEST_IMAGE_CAPTURE_O);
}
}
处理并压缩拍照结果,takePhotoThenToShowImg是一个ImageView控件
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_IMAGE_CAPTURE_O && resultCode == RESULT_OK){
int targetW = takePhotoThenToShowImg.getWidth();
int targetH = takePhotoThenToShowImg.getHeight();
/* Get the size of the image */
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
int photoW = bmOptions.outWidth;
int photoH = bmOptions.outHeight;
/* Figure out which way needs to be reduced less */
int scaleFactor = 1;
if ((targetW > 0) || (targetH > 0)) {
scaleFactor = Math.min(photoW/targetW, photoH/targetH);
}
/* Set bitmap options to scale the image decode target */
bmOptions.inJustDecodeBounds = false;
bmOptions.inSampleSize = scaleFactor;
bmOptions.inPurgeable = true;
/* Decode the JPEG file into a Bitmap */
Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
/* Associate the Bitmap to the ImageView */
takePhotoThenToShowImg.setImageBitmap(bitmap);
galleryAddPic();
}
}
最后可以将拍摄到的照片添加到Media Provider的数据库中，以便图库或者其他程序读取照片
/**
* 将拍摄到的照片添加到Media Provider的数据库中
*/
private void galleryAddPic(){
Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
File f = new File(mCurrentPhotoPath);
Uri contentUri = Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
this.sendBroadcast(mediaScanIntent);
}
如果只需要缩略图的话，只要调摄像头拍摄直接处理结果就行
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK){//展示图片
Bundle extras = data.getExtras();
Bitmap imageBitmap = (Bitmap) extras.get("data");
takePhotoThenToShowImg.setImageBitmap(imageBitmap);
}
}
读完爱站技术频道介绍的Android开发实现ImageView加载摄像头拍摄的大图功能，大家是不是都有了答案呢？我们可以按上述的方法试试，祝大家学习到更多的知识。
