- 声明需要相机支持
<manifest ... >
<uses-feature android:name="android.hardware.camera"
android:required="true" />
...
</manifest>
- 拍照
// request code
static final int REQUEST_IMAGE_CAPTURE = 1;
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// 确保有app响应这个拍照的请求
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
// 调用相机，并等待结果
startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
}
}
- 简单方式取回拍照后的缩略图(thumbnail)
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
Bundle extras = data.getExtras();
Bitmap imageBitmap = (Bitmap) extras.get("data");
mImageView.setImageBitmap(imageBitmap);
}
}
注意：官方文档说，data参数获取到的数据，用于作为icon显示比较好。毕竟是缩略图嘛。
- 保存刚刚拍的照片呢
申请权限先；
<manifest ...>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
...
</manifest>
用一个第三方库EasyPermission，去解决申请权限，参考官方文档或参考这里
1. 照片仅当前app可见
a. 通过使用getExternalFilesDir()获取到存储照片内部存储路径；举个例子有个app是takepic，它内部存储如下：Android/data/com.deao.takepic；文档中提到，Android4.4及其以后版本，访问内部存储不需要申请权限，反之，须声明。
b. 创建保存的图片文件名
// 后续，用于添加到相册，需要这个图片的绝对路径
String mCurrentPhotoPath;
private File createImageFile() throws IOException {
// Create an image file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = "JPEG_" + timeStamp + "_";
File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
/*File storageDir = getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
if (!storageDir.exists()) {
Log.d("TAG", "createImageFile: " + storageDir.mkdir());
}*/
// image 名称大概是：JPEG_20181216_200254_34**53.jpeg
File image = File.createTempFile(
imageFileName, /* prefix */
".jpg", /* suffix */
storageDir /* directory */
);
// Save a file: path for use with ACTION_VIEW intents
mCurrentPhotoPath = image.getAbsolutePath();
return image;
}
创建Intent并调用它如下:
static final int REQUEST_TAKE_PHOTO = 1;
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// Ensure that there's a camera activity to handle the intent
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
// Create the File where the photo should go
File photoFile = null;
try {
photoFile = createImageFile();
} catch (IOException ex) {
// Error occurred while creating the File
...
}
// Continue only if the File was successfully created
if (photoFile != null) {
// authorities="com.deao.takepic.fileprovider"
Uri photoURI = FileProvider.getUriForFile(this,
"com.deao.takepic.fileprovider",
photoFile);
// MUST be thrown FileUriExposedException
// Uri photoURI = Uri.from(photo_file_path);
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
}
}
}
为适配7.0(API 24)或更高版本，通常要用FileProvider来处理路径了。如果还像之前那样传一个类似file://的URI，则会报FileUriExposedException。现在传的是content://的URL。
走，去AndroidManifest文件配置 FileProvider
<application>
...
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="com.deao.takepic.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths"></meta-data>
</provider>
...
</application>
然后，到res/xml/file_paths查看下我们的文件路径配置；
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
<external-files-path name="my_images" path="Android/data/com.deao.takepic/files/Pictures" />
<external-path name="my_images" path="Pictures" />
</paths>
解释：类似于对FileProvider的声明，以上声明了两个路径的请求内容的URI(request content URI)。<external-files-path name="my_images" path="Android/data/com.deao.takepic/files/Pictures" />，声明图片保存到takepic app的私人文件夹内，其他应用都不能访问；<external-path name="my_images" path="Pictures" />，声明到图片保存到外置存储器的Pictures目录下，对设备上所有app可见，当然，添加到相册也是可以的。
更多细节参考这里FileProvider#SpecifyFiles
下面再onActivityResult回调中等待结果。
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
Bundle extras = data.getExtras();
Bitmap imageBitmap = (Bitmap) extras.get("data");
mImageView.setImageBitmap(imageBitmap);
}
// galleryAddPic();
}
2. 照片所有app可见
...
添加到相册(Gallery)
// mCurrentPhotoPath = ""
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);
}
注意事项：如果相片是存储该app到getExternalFileDir()目录下的，media scanner是无法访问的，也就无法添加到相册；其他app也无法访问。
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