Android 10:通过带有位置信息的 MediaStore 获取图库

Android 10: fetch the gallery via MediaStore with location information

查看 Android 10 here 中引入的存储访问更改,现在默认情况下会编辑位置信息。

Google 要求我们使用媒体的 uri 作为参数在“MediaStore”对象上调用 setRequireOriginal()。这在您一个接一个地获取媒体时有效,但是当我们为整个画廊查询 ContentResolver 时呢?

查看此示例:

String[] projection = {
        MediaStore.Files.FileColumns._ID,
        MediaStore.Files.FileColumns.DATA,
        MediaStore.Files.FileColumns.MEDIA_TYPE,
        MediaStore.Images.Media.DATE_TAKEN,
        MediaStore.Images.Media.WIDTH,
        MediaStore.Images.Media.HEIGHT,
        MediaStore.Images.Media.LATITUDE, // <----- THIS
        MediaStore.Images.Media.LONGITUDE, // <----- THIS
        MediaStore.Images.Media.MIME_TYPE,
};

String selection = MediaStore.Files.FileColumns.MEDIA_TYPE + "="
        + MediaStore.Files.FileColumns.MEDIA_TYPE_IMAGE;

Uri queryUri = MediaStore.Files.getContentUri("external");

Cursor cursor = null;
MediaStore a ;

try {
    cursor = context.getContentResolver().query(queryUri, projection, selection,
            null, MediaStore.Images.Media.DATE_TAKEN + " DESC");


}
catch (NullPointerException ex){
}

启动Q,纬度和经度始终设置为0。假设在Manifest中添加了ACCESS_MEDIA_LOCATION权限,是否有办法获取一批媒体的位置数据?

不幸的是,MediaStore.Images.Media.LATITUDE 和 MediaStore.Images.Media.LONGITUDE 是 deprecated in Android Q

The work around 就是这样使用 ExifInterface

Cursor cursor = null;
try {
    String[] projection = {
            MediaStore.Files.FileColumns._ID,
            MediaStore.Images.Media.DATE_TAKEN,
            MediaStore.Images.Media.WIDTH,
            MediaStore.Images.Media.HEIGHT,
            MediaStore.MediaColumns.TITLE,
            MediaStore.Images.Media.MIME_TYPE,
            MediaStore.Images.Media.LATITUDE,
            MediaStore.Images.Media.LONGITUDE
    };
    cursor = getContentResolver().query(
            MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
            projection,
            null,
            null,
            MediaStore.Images.Media.DATE_TAKEN + " DESC");


    int idColumn = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns._ID);
    int titleColumn = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.TITLE);
    int latColumn = BuildCompat.isAtLeastQ() ? -1
            : cursor.getColumnIndexOrThrow(MediaStore.Images.Media.LATITUDE);
    int longColumn = BuildCompat.isAtLeastQ() ? -1
            : cursor.getColumnIndexOrThrow(MediaStore.Images.Media.LONGITUDE);
    while (cursor.moveToNext()) {

        Uri photoUri = Uri.withAppendedPath(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                cursor.getString(idColumn));
        String title = cursor.getString(titleColumn);

        final double[] latLong;
        if (BuildCompat.isAtLeastQ()) {
            photoUri = MediaStore.setRequireOriginal(photoUri);
            InputStream stream = getContentResolver().openInputStream(photoUri);
            if (stream == null) {
                Log.w(TAG, "Got a null input stream for " + photoUri);
                continue;
            }

            ExifInterface exifInterface = new ExifInterface(stream);
            double[] returnedLatLong = exifInterface.getLatLong();
            // If it returns null, fall back to {0.0, 0.0}.
            latLong = returnedLatLong != null ? returnedLatLong : new double[2];

            // After using ExifInterface, the stream should not be reused.
            stream.close();
        } else {
            latLong = new double[]{
                    cursor.getFloat(latColumn),
                    cursor.getFloat(longColumn)
            };
        }

        Log.i(TAG, title + " | lat: " + latLong[0] + " | lng: " + latLong[1]);
    }
} catch (NullPointerException | IOException ex) {
    Log.e(TAG, "Caught exception", ex);
} finally {
    if (cursor != null) {
        cursor.close();
    }
}

这是目前在 Android Q 上获取照片经纬度的唯一方法。

这需要按住 ACCESS_MEDIA_LOCATION permission. Note, this permission is not "user visible in the settings UI" (source),这意味着用户不会看到请求权限的弹出窗口,即使它是运行时权限。这意味着您必须在运行时请求许可(与清单文件不同),但用户不必同意。在这里添加它是因为您可能想知道为什么没有显示额外的 UI 弹出窗口。