Reprinted from: [ https://blog.csdn.net/zz110753/article/details/60877594]
Some questions about Android7.0 calling the system camera to take pictures and access albums:
In Android 6.0, Google proposed the Api to dynamically apply for permissions, calling the camera to take pictures, accessing SDcard and other operations need to first apply for the corresponding permissions as follows:
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />Google is against relaxing the access rights of private directories, so it is the future development trend of Android to put away access rights to private files.
In Android 7.0, trying to pass a file:// URI will trigger a FileUriExposedException, because after Android 7.0, Google believes that it is unsafe to use the local root directory, that is, the file:// URI. Direct access will throw a FileUriExposedExCeption exception, which It means that before Android 7.0, when we access the camera's photo storage, if we use the URI method to directly store the cropped image, this exception will be caused, so how to solve this problem? (A link to the demo will be attached at the end of the article)
Supplementary note: The Demo in this article is to access the camera and album directly in the activity. After the release, many brothers left a message saying that they need to be used in Fragment. For everyone's convenience, the blogger added a Demo called in the fragment. At the end of the article, I will Links to two demos will be attached.
Google provides us with the FileProvider class to provide a special kind of content. FileProvider is a subclass of ContentProvide. It uses a mechanism similar to the content provider to protect data and can selectively share the encapsulated Uri with external, thereby improving the security of the application. Let's take a look at how to use this content provider for data access:
Using FileProvider to obtain Uri will replace the previous file:// URI with content:// URI to achieve a secure data access between applications. As one of the four components of Android, the content provider also needs to be used in the list. Registered in the file AndroidManifest.xml, the registration method is as follows:
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="com.zz.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths" />
</provider>The value of android:name in the provider tag is the fixed value of FileProvider's package name + class name. The value of android:authorities is equivalent to a flag. When we use the getUriForFile method of FileProvider, a parameter needs to be consistent with the registration of the manifest file. Here I use: com.zz.fileprovider can be defined by itself. exported: The requirement must be false. If it is true, a security exception will be reported. grantUriPermissions:true, which grants temporary access to the URI. The label is used to specify the shared path. android:resource=”@xml/file_paths” is the xml file of our shared path configuration. The configuration of the xml file is as follows:
Create an xml folder in the res directory. The content of the file_paths.xml file is as follows:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<paths>
<external-path
name="camera_photos"
path="" />
</paths>
</resources>The external-path tag is used to specify the Uri shared. The value of the name attribute can be customized. The value of the path attribute indicates the specific location of the sharing. If it is set to empty, it means that the entire SD card is shared, and the file directory under the corresponding SD card can also be specified. , and define it according to your needs. The next step is to call the system camera to take pictures. The code is as follows:
First get the camera and access SDcard permissions:
/**
* 自动获取相机权限
*/
private void autoObtainCameraPermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED
|| ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)) {
ToastUtils.showShort(this, "您已经拒绝过一次");
}
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA, Manifest.permission.READ_EXTERNAL_STORAGE}, CAMERA_PERMISSIONS_REQUEST_CODE);
} else {//有权限直接调用系统相机拍照
if (hasSdcard()) {
imageUri = Uri.fromFile(fileUri);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
imageUri = FileProvider.getUriForFile(MainActivity.this, "com.zz.fileprovider", fileUri);//通过FileProvider创建一个content类型的Uri
PhotoUtils.takePicture(this, imageUri, CODE_CAMERA_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
}
}Callback method for dynamically applying for permissions:
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case CAMERA_PERMISSIONS_REQUEST_CODE: {//调用系统相机申请拍照权限回调
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (hasSdcard()) {
imageUri = Uri.fromFile(fileUri);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
imageUri = FileProvider.getUriForFile(MainActivity.this, "com.zz.fileprovider", fileUri);//通过FileProvider创建一个content类型的Uri
PhotoUtils.takePicture(this, imageUri, CODE_CAMERA_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
} else {
ToastUtils.showShort(this, "请允许打开相机！！");
}
break;
}
case STORAGE_PERMISSIONS_REQUEST_CODE://调用系统相册申请Sdcard权限回调
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
PhotoUtils.openPic(this, CODE_GALLERY_REQUEST);
} else {
ToastUtils.showShort(this, "请允许打操作SDCard！！");
}
break;
}
}*Note: PhotoUtils is the encapsulation of bloggers for taking photos and photos from albums. It will be given below. The PhotoUtils class and the complete MainActivity class
focus on the acquisition of imageUri. In the code, imageUri is the Uri used to store the photos after taking pictures. Call the camera to take pictures. First judge the system version before. AndroidN, that is, the system above Android 7.0 obtains the Uri method through FileProvider. The parameters are, respectively, the context object, the android:authorities configured in the manifest file, and the corresponding picture stored in the camera. After that, the system camera is called through PhotoUtils to take pictures.
The corresponding code of PhotoUtils is as follows:
/**
* @param activity 当前activity
* @param imageUri 拍照后照片存储路径
* @param requestCode 调用系统相机请求码
*/
public static void takePicture(Activity activity, Uri imageUri, int requestCode) {
//调用系统相机
Intent intentCamera = new Intent();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
intentCamera.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION); //添加这一句表示对目标应用临时授权该Uri所代表的文件
}
intentCamera.setAction(MediaStore.ACTION_IMAGE_CAPTURE);
//将拍照结果保存至photo_file的Uri中，不保留在相册中
intentCamera.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
activity.startActivityForResult(intentCamera, requestCode);
}Method description: Use the Intent to call the system camera to take pictures. If the local version is greater than or equal to anroid7.0, you need to temporarily authorize the Uri's access rights as follows:
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
Other parts are the same as the normal call to the system camera before.
The next step is to crop the finished photo:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
switch (requestCode) {
case CODE_CAMERA_REQUEST://拍照完成回调
cropImageUri = Uri.fromFile(fileCropUri);
PhotoUtils.cropImageUri(this, imageUri, cropImageUri, 1, 1, output_X, output_Y, CODE_RESULT_REQUEST);
break;
case CODE_GALLERY_REQUEST://访问相册完成回调
if (hasSdcard()) {
cropImageUri = Uri.fromFile(fileCropUri);
Uri newUri = Uri.parse(PhotoUtils.getPath(this, data.getData()));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
newUri = FileProvider.getUriForFile(this, "com.zz.fileprovider", new File(newUri.getPath()));
PhotoUtils.cropImageUri(this, newUri, cropImageUri, 1, 1, output_X, output_Y, CODE_RESULT_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
break;
case CODE_RESULT_REQUEST:
Bitmap bitmap = PhotoUtils.getBitmapFromUri(cropImageUri, this);
if (bitmap != null) {
showImages(bitmap);
}
break;
}
}
}The clipping code is as follows:
/**
* @param activity 当前activity
* @param orgUri 剪裁原图的Uri
* @param desUri 剪裁后的图片的Uri
* @param aspectX X方向的比例
* @param aspectY Y方向的比例
* @param width 剪裁图片的宽度
* @param height 剪裁图片高度
* @param requestCode 剪裁图片的请求码
*/
public static void cropImageUri(Activity activity, Uri orgUri, Uri desUri, int aspectX, int aspectY, int width, int height, int requestCode) {
Intent intent = new Intent("com.android.camera.action.CROP");
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
}
intent.setDataAndType(orgUri, "image/*");
intent.putExtra("crop", "true");
intent.putExtra("aspectX", aspectX);
intent.putExtra("aspectY", aspectY);
intent.putExtra("outputX", width);
intent.putExtra("outputY", height);
intent.putExtra("scale", true);
//将剪切的图片保存到目标Uri中
intent.putExtra(MediaStore.EXTRA_OUTPUT, desUri);
intent.putExtra("return-data", false);
intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
intent.putExtra("noFaceDetection", true);
activity.startActivityForResult(intent, requestCode);
}It is basically the same as the previous normal clipping code. It is the same as the above intention to open the camera. If the local version is greater than or equal to anroid7.0, the access rights of Uri need to be temporarily authorized as follows: intent.addFlags
(Intent.FLAG_GRANT_READ_URI_PERMISSION);
The cropping is completed, and the cropped photo is stored in the corresponding path of cropImageUri.
The code to access the album is as follows:
/**
* @param activity 当前activity
* @param requestCode 打开相册的请求码
*/
public static void openPic(Activity activity, int requestCode) {
Intent photoPickerIntent = new Intent(Intent.ACTION_GET_CONTENT);
photoPickerIntent.setType("image/*");
activity.startActivityForResult(photoPickerIntent, requestCode);
}The callback of onActivityResult after accessing the album has been posted above, and the main operation is the same to parse the Uri call to crop the picture:
if (hasSdcard()) {
cropImageUri = Uri.fromFile(fileCropUri);
Uri newUri = Uri.parse(PhotoUtils.getPath(this, data.getData()));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
newUri = FileProvider.getUriForFile(this, "com.zz.fileprovider", new File(newUri.getPath()));
PhotoUtils.cropImageUri(this, newUri, cropImageUri, 1, 1, output_X, output_Y, CODE_RESULT_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
break;*Note: After Android 4.4, the selected picture no longer returns the real Uri, but the encapsulated Uri, so in 4.4 and above, the Uri must be parsed, that is, the PhotoUtils.getPath() method above,
specifically For the analysis of Uri, see PhotoUtils class. Before android4.4, the real Uri can be obtained directly by data.getData without parsing.
After parsing and obtaining the real Uri, the same image can be cropped after judging that the system version starts to obtain the new Uri through the FileProvider.
The MainActivity code is as follows:
package choicemmed.com.android60permissionsdemo;
import android.Manifest;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.Matrix;
import android.media.ExifInterface;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import com.google.android.gms.common.api.GoogleApiClient;
import com.lidroid.xutils.ViewUtils;
import com.lidroid.xutils.view.annotation.ViewInject;
import com.lidroid.xutils.view.annotation.event.OnClick;
import java.io.File;
import de.hdodenhof.circleimageview.CircleImageView;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private static final String TAG = "MainActivity";
@ViewInject(R.id.photo)
private CircleImageView photo;
@ViewInject(R.id.takePic)
private Button takePic;
@ViewInject(R.id.takeGallery)
private Button takeGallery;
@ViewInject(R.id.test)
private Button test;
private static final int CODE_GALLERY_REQUEST = 0xa0;
private static final int CODE_CAMERA_REQUEST = 0xa1;
private static final int CODE_RESULT_REQUEST = 0xa2;
private static final int CAMERA_PERMISSIONS_REQUEST_CODE = 0x03;
private static final int STORAGE_PERMISSIONS_REQUEST_CODE = 0x04;
private File fileUri = new File(Environment.getExternalStorageDirectory().getPath() + "/photo.jpg");
private File fileCropUri = new File(Environment.getExternalStorageDirectory().getPath() + "/crop_photo.jpg");
private Uri imageUri;
private Uri cropImageUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewUtils.inject(this);
}
@OnClick({R.id.takePic, R.id.takeGallery})
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.takePic:
autoObtainCameraPermission();
break;
case R.id.takeGallery:
autoObtainStoragePermission();
break;
}
}
/**
* 自动获取相机权限
*/
private void autoObtainCameraPermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED
|| ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)) {
ToastUtils.showShort(this, "您已经拒绝过一次");
}
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA, Manifest.permission.READ_EXTERNAL_STORAGE}, CAMERA_PERMISSIONS_REQUEST_CODE);
} else {//有权限直接调用系统相机拍照
if (hasSdcard()) {
imageUri = Uri.fromFile(fileUri);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
imageUri = FileProvider.getUriForFile(MainActivity.this, "com.zz.fileprovider", fileUri);//通过FileProvider创建一个content类型的Uri
PhotoUtils.takePicture(this, imageUri, CODE_CAMERA_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case CAMERA_PERMISSIONS_REQUEST_CODE: {//调用系统相机申请拍照权限回调
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (hasSdcard()) {
imageUri = Uri.fromFile(fileUri);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
imageUri = FileProvider.getUriForFile(MainActivity.this, "com.zz.fileprovider", fileUri);//通过FileProvider创建一个content类型的Uri
PhotoUtils.takePicture(this, imageUri, CODE_CAMERA_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
} else {
ToastUtils.showShort(this, "请允许打开相机！！");
}
break;
}
case STORAGE_PERMISSIONS_REQUEST_CODE://调用系统相册申请Sdcard权限回调
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
PhotoUtils.openPic(this, CODE_GALLERY_REQUEST);
} else {
ToastUtils.showShort(this, "请允许打操作SDCard！！");
}
break;
}
}
private int output_X = 480;
private int output_Y = 480;
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
switch (requestCode) {
case CODE_CAMERA_REQUEST://拍照完成回调
cropImageUri = Uri.fromFile(fileCropUri);
PhotoUtils.cropImageUri(this, imageUri, cropImageUri, 1, 1, output_X, output_Y, CODE_RESULT_REQUEST);
break;
case CODE_GALLERY_REQUEST://访问相册完成回调
if (hasSdcard()) {
cropImageUri = Uri.fromFile(fileCropUri);
Uri newUri = Uri.parse(PhotoUtils.getPath(this, data.getData()));
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N)
newUri = FileProvider.getUriForFile(this, "com.zz.fileprovider", new File(newUri.getPath()));
PhotoUtils.cropImageUri(this, newUri, cropImageUri, 1, 1, output_X, output_Y, CODE_RESULT_REQUEST);
} else {
ToastUtils.showShort(this, "设备没有SD卡！");
}
break;
case CODE_RESULT_REQUEST:
Bitmap bitmap = PhotoUtils.getBitmapFromUri(cropImageUri, this);
if (bitmap != null) {
showImages(bitmap);
}
break;
}
}
}
/**
* 自动获取sdk权限
*/
private void autoObtainStoragePermission() {
if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, STORAGE_PERMISSIONS_REQUEST_CODE);
} else {
PhotoUtils.openPic(this, CODE_GALLERY_REQUEST);
}
}
private void showImages(Bitmap bitmap) {
photo.setImageBitmap(bitmap);
}
/**
* 检查设备是否存在SDCard的工具方法
*/
public static boolean hasSdcard() {
String state = Environment.getExternalStorageState();
return state.equals(Environment.MEDIA_MOUNTED);
}
}The PhotoUtils code is as follows:
package choicemmed.com.android60permissionsdemo;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.ContentUris;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
/**
* Created by:zheng zhong on 2016/8/6 16:16
* Email [email protected]
*/
public class PhotoUtils {
private static final String TAG = "PhotoUtils";
/**
* @param activity 当前activity
* @param imageUri 拍照后照片存储路径
* @param requestCode 调用系统相机请求码
*/
public static void takePicture(Activity activity, Uri imageUri, int requestCode) {
//调用系统相机
Intent intentCamera = new Intent();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
intentCamera.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION); //添加这一句表示对目标应用临时授权该Uri所代表的文件
}
intentCamera.setAction(MediaStore.ACTION_IMAGE_CAPTURE);
//将拍照结果保存至photo_file的Uri中，不保留在相册中
intentCamera.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
activity.startActivityForResult(intentCamera, requestCode);
}
/**
* @param activity 当前activity
* @param requestCode 打开相册的请求码
*/
public static void openPic(Activity activity, int requestCode) {
Intent photoPickerIntent = new Intent(Intent.ACTION_GET_CONTENT);
photoPickerIntent.setType("image/*");
activity.startActivityForResult(photoPickerIntent, requestCode);
}
/**
* @param activity 当前activity
* @param orgUri 剪裁原图的Uri
* @param desUri 剪裁后的图片的Uri
* @param aspectX X方向的比例
* @param aspectY Y方向的比例
* @param width 剪裁图片的宽度
* @param height 剪裁图片高度
* @param requestCode 剪裁图片的请求码
*/
public static void cropImageUri(Activity activity, Uri orgUri, Uri desUri, int aspectX, int aspectY, int width, int height, int requestCode) {
Intent intent = new Intent("com.android.camera.action.CROP");
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
}
intent.setDataAndType(orgUri, "image/*");
intent.putExtra("crop", "true");
intent.putExtra("aspectX", aspectX);
intent.putExtra("aspectY", aspectY);
intent.putExtra("outputX", width);
intent.putExtra("outputY", height);
intent.putExtra("scale", true);
//将剪切的图片保存到目标Uri中
intent.putExtra(MediaStore.EXTRA_OUTPUT, desUri);
intent.putExtra("return-data", false);
intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
intent.putExtra("noFaceDetection", true);
activity.startActivityForResult(intent, requestCode);
}
/**
* 读取uri所在的图片
*
* @param uri 图片对应的Uri
* @param mContext 上下文对象
* @return 获取图像的Bitmap
*/
public static Bitmap getBitmapFromUri(Uri uri, Context mContext) {
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(mContext.getContentResolver(), uri);
return bitmap;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* @param context 上下文对象
* @param uri 当前相册照片的Uri
* @return 解析后的Uri对应的String
*/
@SuppressLint("NewApi")
public static String getPath(final Context context, final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
String pathHead = "file:///";
// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
if ("primary".equalsIgnoreCase(type)) {
return pathHead + Environment.getExternalStorageDirectory() + "/" + split[1];
}
}
// DownloadsProvider
else if (isDownloadsDocument(uri)) {
final String id = DocumentsContract.getDocumentId(uri);
final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
return pathHead + getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
} else if ("video".equals(type)) {
contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
} else if ("audio".equals(type)) {
contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
}
final String selection = "_id=?";
final String[] selectionArgs = new String[]{split[1]};
return pathHead + getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {
return pathHead + getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return pathHead + uri.getPath();
}
return null;
}
/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
private static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
Cursor cursor = null;
final String column = "_data";
final String[] projection = {column};
try {
cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
if (cursor != null && cursor.moveToFirst()) {
final int column_index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(column_index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
private static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
private static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
private static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
}Finally attached:
1. GitHub address for calling demo in Activity: Click to open the link
2. The GitHub address for calling Demo in Fragment: Click to open the link
About Android7.0 calling the system camera to take pictures and accessing the system photo album is probably like this. If you have any other questions, please leave a message and correct me