android 直接访问相册图片

官方总结

https://developer.android.google.cn/training/data-storage?hl=zh-cn

Demo (MediaStore 访问相册图片)

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

/data/data/com.android.providers.media.module/databases/external.db
不同系统版本该文件位于不同目录下，/data/data/com.android.providers.media xxx/external.db

package com.cuncaojin.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.Manifest;
import android.annotation.SuppressLint;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.widget.ImageView;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import pub.devrel.easypermissions.AfterPermissionGranted;
import pub.devrel.easypermissions.EasyPermissions;

/**
 * 外部存储数据库文件：/data/data/com.android.providers.media.module/databases/external.db,
 * 不同版本位置略有不同，有的在/data/data/com.android.providers.media/databases/external.db
 * 

 * su root
 * 

 * cd /data/data/com.android.providers.media.module/databases && ls -l
 * 

 * -rw-rw---- 1 u0_a119 u0_a119 131072 2022-03-07 14:23 external.db
 * -rw------- 1 u0_a119 u0_a119  32768 2022-03-07 16:31 external.db-shm
 * -rw------- 1 u0_a119 u0_a119 477952 2022-03-07 16:31 external.db-wal
 * -rw-rw---- 1 u0_a119 u0_a119 233472 2022-03-07 16:31 internal.db
 * -rw------- 1 u0_a119 u0_a119  32768 2022-03-07 16:31 internal.db-shm
 * -rw------- 1 u0_a119 u0_a119 524288 2022-03-07 16:31 internal.db-wal
 */
public class MainActivity extends AppCompatActivity {
    public static final String SIMPLE_IMAGE_NAME = "IMG_20220307_142202.jpg";
    public static final String SIMPLE_IMAGE_NAME2 = "IMG_20220307_141816.jpg";

    private ImageView iv;
    private ImageView iv2;
    private Uri mUri;
    private Uri mUri2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        iv = findViewById(R.id.imageView);
        iv2 = findViewById(R.id.imageView2);

        requiresPermissions();
    }

    public static Uri getImageStreamFromExternal(String imageName) {
        File externalPubPath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
        File imageFile = new File(externalPubPath, imageName);
        // 等价
        // File imageFile = new File("/storage/emulated/0/Pictures/IMG_20220307_142202.jpg");

        Uri uri = null;
        if (imageFile.exists()) {
            uri = Uri.fromFile(imageFile);
        }
        return uri;
    }

    @SuppressLint("Range")
    public static Uri getMediaUriFromPath(Context context, String path) {
        Uri mediaUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        Cursor cursor = context.getContentResolver().query(mediaUri,
                null,
                MediaStore.Images.Media.DISPLAY_NAME + "= ?",
                new String[]{path.substring(path.lastIndexOf("/") + 1)},
                null);

        Uri uri = null;
        if (cursor.moveToFirst()) {
            uri = ContentUris.withAppendedId(mediaUri,
                    cursor.getLong(cursor.getColumnIndex(MediaStore.Images.Media._ID)));
        }
        cursor.close();
        return uri;
    }

    public List<Uri> getAllShownImagesPath() {
        Uri uriExternal = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        Cursor cursor;
        int columnIndexID;
        List<Uri> listOfAllImages = new ArrayList<>();
        // /data/data/com.android.providers.media.module/databases/external.db
        // SELECT _id,
        //        _display_name
        //        _data,
        //   FROM images;
        // 45	/storage/emulated/0/Pictures/IMG_20220307_142051.jpg	IMG_20220307_142051.jpg
        String[] projection = new String[]{MediaStore.Images.Media._ID, MediaStore.Images.Media.DISPLAY_NAME, MediaStore.Images.Media.DATA};
        Long imageId;
        cursor = getContentResolver().query(uriExternal, projection, null, null, null);
        if (cursor != null) {
            columnIndexID = cursor.getColumnIndexOrThrow(MediaStore.Images.Media._ID);
            int simpleNamePathId = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DISPLAY_NAME);
            // 废弃字段，不要用
            int fullNamePathId = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            while (cursor.moveToNext()) {
                imageId = cursor.getLong(columnIndexID);
                String simpleNamePath = cursor.getString(simpleNamePathId);
                String fullNamePath = cursor.getString(fullNamePathId);

                if (SIMPLE_IMAGE_NAME2.equals(simpleNamePath)) {
                    mUri2 = ContentUris.withAppendedId(uriExternal, imageId);// 或 Uri uriImage = Uri.withAppendedPath(uriExternal, "" + imageId);
                }
                Uri uriImage = ContentUris.withAppendedId(uriExternal, imageId);// 或 Uri uriImage = Uri.withAppendedPath(uriExternal, "" + imageId);
                listOfAllImages.add(uriImage);
            }
            cursor.close();
        }
        return listOfAllImages;
    }

    private void showAlbumPicture() {
        try {
            // 左图
            mUri = getImageStreamFromExternal(SIMPLE_IMAGE_NAME);
            Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), mUri);
            iv.setImageBitmap(bitmap);

            // 右图
            getAllShownImagesPath();
            Bitmap bitmap2 = MediaStore.Images.Media.getBitmap(getContentResolver(), mUri2);
            iv2.setImageBitmap(bitmap2);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /// EasyPermissions start /
    public static final int EXTERNAL_STORAGE_REQUEST_CODE = 111;

    @AfterPermissionGranted(EXTERNAL_STORAGE_REQUEST_CODE)
    private void requiresPermissions() {
        String[] perms = {Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE};
        if (EasyPermissions.hasPermissions(this, perms)) {
            // Already have permission, do the thing
            showAlbumPicture();
        } else {
            // Do not have permissions, request them now
            EasyPermissions.requestPermissions(this, getString(R.string.app_name),
                    EXTERNAL_STORAGE_REQUEST_CODE, perms);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        // Forward results to EasyPermissions
        EasyPermissions.onRequestPermissionsResult(requestCode, permissions, grantResults, this);
    }
    /// EasyPermissions end /
}