本文实例讲述了Android开发实现ImageView加载摄像头拍摄的大图功能。分享给大家供大家参考，具体如下：
这个方法是从官方demo中摘录的，在此记录学习。
权限
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-feature android:name="android.hardware.camera2" android:required="false" />
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); } }
更多关于Android相关内容感兴趣的读者可查看本站专题：《Android拍照与图片处理技巧总结》、《Android图形与图像处理技巧总结》、《Android开发入门与进阶教程》、《Android调试技巧与常见问题解决方法汇总》、《Android基本组件用法总结》、《Android视图View技巧总结》、《Android布局layout技巧总结》及《Android控件用法总结》
希望本文所述对大家Android程序设计有所帮助。