Question

SDK版本 - 1.6

我正在使用以下意图打开android的默认图库：

Intent intent = new Intent();
                intent.setType("image/*");
                intent.setAction(Intent.ACTION_GET_CONTENT);
                startActivityForResult(
                        Intent.createChooser(intent, "Select Picture"), 101);

现在在onActivityResult，我能够获得所选图像的原始Uri和路径，但是我无法获得所选图像的缩略图的Uri和路径。

获取原始图像的代码Uri和路径：

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        try {

            if (requestCode == 101 && data != null) {

                Uri selectedImageUri = data.getData();
                String selectedImagePath = getPath(selectedImageUri);
} else {
                Toast toast = Toast.makeText(this, "No Image is selected.",
                        Toast.LENGTH_LONG);
                toast.show();
            }

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public String getPath(Uri uri) {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(uri, projection, null, null, null);
        int column_index = cursor
                .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);

        cursor.moveToFirst();
        return cursor.getString(column_index);
    }

PS：1）我不打算像question那样调整图片大小。我特意寻找由Android OS本身生成的缩略图。

2）使用SDK版本1.6，因此对ThumbnailUtils类不感兴趣。

Answer 1

您可以使用它来获取缩略图：

Bitmap bitmap = MediaStore.Images.Thumbnails.getThumbnail(
                             getContentResolver(), selectedImageUri,
                             MediaStore.Images.Thumbnails.MINI_KIND,
                             (BitmapFactory.Options) null );

有两种类型的缩略图：
MINI_KIND：512 x 384缩略图
MICRO_KIND：96 x 96缩略图

或者使用几乎相同参数的[queryMiniThumbnails] [1]来获取缩略图的路径。

修改

Cursor cursor = MediaStore.Images.Thumbnails.queryMiniThumbnails( getContentResolver(), selectedImageUri, MediaStore.Images.Thumbnails.MINI_KIND, null ); if( cursor != null && cursor.getCount() > 0 ) { cursor.moveToFirst();//**EDIT** String uri = cursor.getString( cursor.getColumnIndex( MediaStore.Images.Thumbnails.DATA ) ); }

HTH！

[1]：https://developer.android.com/reference/android/provider/MediaStore.Images.Thumbnails.html#queryMiniThumbnails(android.content.ContentResolver，android.net.Uri，int，java.lang.String []）

Answer 2

This解决方案对我有用！

final int THUMBSIZE = 128;

Bitmap thumbImage = ThumbnailUtils.extractThumbnail(
                         BitmapFactory.decodeFile(file.getAbsolutePath()), 
                         THUMBSIZE, 
                         THUMBSIZE);

Answer 3

它可能是其他方式已经在他们的答案中提到的替代方式，但我发现获取缩略图的简单方法是使用ExifInterface

ExifInterface exif = new ExifInterface(pictureFile.getPath());
byte[] imageData=exif.getThumbnail();
Bitmap  thumbnail= BitmapFactory.decodeByteArray(imageData,0,imageData.length);

Answer 4

两种没有弃用方法的变体。

 public String getThumbnailPath(Uri uri) {
    String[] proj = { MediaStore.Images.Media.DATA };

    // This method was deprecated in API level 11
    // Cursor cursor = managedQuery(contentUri, proj, null, null, null);

    CursorLoader cursorLoader = new CursorLoader(activity, uri, proj, null, null, null);
Cursor cursor = cursorLoader.loadInBackground();

    int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media._ID);

    cursor.moveToFirst();
    long imageId = cursor.getLong(column_index);
    //cursor.close();
    String result="";
    cursor = MediaStore.Images.Thumbnails.queryMiniThumbnail(activity.getContentResolver(), imageId,
            MediaStore.Images.Thumbnails.MINI_KIND, null);
    if (cursor != null && cursor.getCount() > 0) {
        cursor.moveToFirst();
        result = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Thumbnails.DATA));
        cursor.close();
    }
    return result;
}
public Bitmap getThumbnailBitmap(Uri uri){
    String[] proj = { MediaStore.Images.Media.DATA };

    // This method was deprecated in API level 11
    // Cursor cursor = managedQuery(contentUri, proj, null, null, null);

    CursorLoader cursorLoader = new CursorLoader(activity, uri, proj, null, null, null);
    Cursor cursor = cursorLoader.loadInBackground();

    int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media._ID);

    cursor.moveToFirst();
    long imageId = cursor.getLong(column_index);
    //cursor.close();

    Bitmap bitmap = MediaStore.Images.Thumbnails.getThumbnail(
            getContentResolver(), imageId,
            MediaStore.Images.Thumbnails.MINI_KIND,
            (BitmapFactory.Options) null );

    return bitmap;
}

Answer 5

基于@Karan的回答和以下评论，仅针对到达此处的人（就像我一样）并需要一个现成的代码：

public String getThumbnailPath(Uri uri) {
    String[] projection = { MediaStore.Images.Media._ID };
    String result = null;
    Cursor cursor = managedQuery(uri, projection, null, null, null);
    int column_index = cursor
            .getColumnIndexOrThrow(MediaStore.Images.Media._ID);

    cursor.moveToFirst();
    long imageId = cursor.getLong(column_index);
    cursor.close();

    cursor = MediaStore.Images.Thumbnails.queryMiniThumbnail(
            getContentResolver(), imageId,
            MediaStore.Images.Thumbnails.MINI_KIND,
            null);
    if (cursor != null && cursor.getCount() > 0) {
        cursor.moveToFirst();
        result = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Thumbnails.DATA));
        cursor.close();
    }
    return result;
}

Answer 6

看看下面的课程

http://developer.android.com/reference/android/provider/MediaStore.Images.Thumbnails.html

Answer 7

public static String getThumbnailPath(Context context, String path)
{
  long imageId = -1;

  String[] projection = new String[] { MediaStore.MediaColumns._ID };
  String selection = MediaStore.MediaColumns.DATA + "=?";
  String[] selectionArgs = new String[] { path };
  Cursor cursor = context.getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, projection, selection, selectionArgs, null);
  if (cursor != null && cursor.moveToFirst())
  {
    imageId = cursor.getInt(cursor.getColumnIndex(MediaStore.MediaColumns._ID));
    cursor.close();
  }

  String result = null;
  cursor = MediaStore.Images.Thumbnails.queryMiniThumbnail(context.getContentResolver(), imageId, MediaStore.Images.Thumbnails.MINI_KIND, null);
  if (cursor != null && cursor.getCount() > 0)
  {
    cursor.moveToFirst();
    result = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Thumbnails.DATA));
    cursor.close();
  }

  return result;
}

Answer 8

接受的答案对我不起作用。我使用以下方法来实现它：

p <- ggplot(mtcars, aes(x=mpg, y=cyl))+
    geom_bar(stat = "identity")+
    theme_tufte()

tickmarks <- ggplot_build(p)$layout$panel_ranges[[1]]$y.major_source  

p + geom_hline(yintercept = tickmarks, col="white", lwd=3)

Answer 9

获取缩略图和所有 Android 版本的最佳答案是：

val thumbnail: Bitmap = if ((Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)) {
    mContentResolver.loadThumbnail(contentUri, Size.parseSize(""), null)
} else {
    MediaStore.Images.Thumbnails.getThumbnail(mContentResolver, id, MediaStore.Images.Thumbnails.MINI_KIND, null)
}

获取存储在SD卡+ android中的缩略图Uri /图像路径

9 个答案: