Java 如何使用MediaStore在Android Q中保存图像？

这里有一个新安卓Q的链接

根据，存储共享媒体文件（这是我的情况）应该使用API来完成

翻阅文档，我找不到相关功能

这是我在科特林的审判：

val bitmap = getImageBitmap() // I have a bitmap from a function or callback or whatever
val name = "example.png" // I have a name

val picturesDirectory = getExternalFilesDir(Environment.DIRECTORY_PICTURES)!!

// Make sure the directory "Android/data/com.mypackage.etc/files/Pictures" exists
if (!picturesDirectory.exists()) {
    picturesDirectory.mkdirs()
}

try {
    val out = FileOutputStream(File(picturesDirectory, name))
    bitmap.compress(Bitmap.CompressFormat.PNG, 100, out)

    out.flush()
    out.close()

} catch(e: Exception) {
    // handle the error
}

结果是，我的图像保存在这里

Android/data/com.mypackage.etc/files/Pictures/example.png

，如最佳实践博客中所述

存储应用程序内部文件

---

我的问题是:

如何使用MediaStore API保存图像

---

Java的答案同样可以接受

提前谢谢

---

编辑

多亏了PerracoLabs

这真的很有帮助

但还有3点

这是我的密码：

val name = "Myimage"
val relativeLocation = Environment.DIRECTORY_PICTURES + File.pathSeparator + "AppName"

val contentValues  = ContentValues().apply {
    put(MediaStore.Images.ImageColumns.DISPLAY_NAME, name)
    put(MediaStore.MediaColumns.MIME_TYPE, "image/png")

    // without this part causes "Failed to create new MediaStore record" exception to be invoked (uri is null below)
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        put(MediaStore.Images.ImageColumns.RELATIVE_PATH, relativeLocation)
    }
}

val contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
var stream: OutputStream? = null
var uri: Uri? = null

try {
    uri = contentResolver.insert(contentUri, contentValues)
    if (uri == null)
    {
        throw IOException("Failed to create new MediaStore record.")
    }

    stream = contentResolver.openOutputStream(uri)

    if (stream == null)
    {
        throw IOException("Failed to get output stream.")
    }

    if (!bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream))
    {
        throw IOException("Failed to save bitmap.")
    }


    Snackbar.make(mCoordinator, R.string.image_saved_success, Snackbar.LENGTH_INDEFINITE).setAction("Open") {
        val intent = Intent()
        intent.type = "image/*"
        intent.action = Intent.ACTION_VIEW
        intent.data = contentUri
        startActivity(Intent.createChooser(intent, "Select Gallery App"))
    }.show()

} catch(e: IOException) {
    if (uri != null)
    {
        contentResolver.delete(uri, null, null)
    }

    throw IOException(e)

}
finally {
    stream?.close()
}

1-保存的图像没有正确的名称“Myimage.png”

我试着使用“Myimage”和“Myimage.PNG”，但都不起作用

图像的名称总是由数字组成，如：

156348625314.jpg

这就引出了第二个问题：

2-图像保存为

jpg

，即使我将位图压缩为

png

格式

这不是什么大问题。只是好奇为什么

3-relativeLocation位在低于Android Q的设备上导致异常。 在使用“Android版本检查”if语句后，图像将直接保存在

图片

文件夹的根目录中

再次谢谢你

---

编辑2

改为：

uri = contentResolver.insert(contentUri, contentValues)
if (uri == null)
{
    throw IOException("Failed to create new MediaStore record.")
}

val cursor = contentResolver.query(uri, null, null, null, null)
DatabaseUtils.dumpCursor(cursor)
cursor!!.close()

stream = contentResolver.openOutputStream(uri)

这是日志

I/System.out: >>>>> Dumping cursor android.content.ContentResolver$CursorWrapperInner@76da9d1
I/System.out: 0 {
I/System.out:    _id=25417
I/System.out:    _data=/storage/emulated/0/Pictures/1563640732667.jpg
I/System.out:    _size=null
I/System.out:    _display_name=Myimage
I/System.out:    mime_type=image/png
I/System.out:    title=1563640732667
I/System.out:    date_added=1563640732
I/System.out:    is_hdr=null
I/System.out:    date_modified=null
I/System.out:    description=null
I/System.out:    picasa_id=null
I/System.out:    isprivate=null
I/System.out:    latitude=null
I/System.out:    longitude=null
I/System.out:    datetaken=null
I/System.out:    orientation=null
I/System.out:    mini_thumb_magic=null
I/System.out:    bucket_id=-1617409521
I/System.out:    bucket_display_name=Pictures
I/System.out:    width=null
I/System.out:    height=null
I/System.out:    is_hw_privacy=null
I/System.out:    hw_voice_offset=null
I/System.out:    is_hw_favorite=null
I/System.out:    hw_image_refocus=null
I/System.out:    album_sort_index=null
I/System.out:    bucket_display_name_alias=null
I/System.out:    is_hw_burst=0
I/System.out:    hw_rectify_offset=null
I/System.out:    special_file_type=0
I/System.out:    special_file_offset=null
I/System.out:    cam_perception=null
I/System.out:    cam_exif_flag=null
I/System.out: }
I/System.out: <<<<<

我不能改变名字的日期

和

MediaStore.MediaColumns.DATA

不推荐使用

---

提前谢谢

试试下一种方法。Android Q（及以上版本）已经负责创建不存在的文件夹。该示例硬编码为输出到DCIM文件夹。如果需要子文件夹，请将子文件夹名称追加为下一步：

final String relativeLocation = Environment.DIRECTORY_DCIM + File.separator + “YourSubforderName”;

考虑压缩格式应该与mime类型参数相关。例如，对于JPEG压缩格式，mime类型将是“image/JPEG”，依此类推。您可能还希望将压缩质量作为参数传递，在本例中，压缩质量硬编码为95

Java:

@NonNull
public Uri saveBitmap(@NonNull final Context context, @NonNull final Bitmap bitmap,
                      @NonNull final Bitmap.CompressFormat format,
                      @NonNull final String mimeType,
                      @NonNull final String displayName) throws IOException {

    final ContentValues values = new ContentValues();
    values.put(MediaStore.MediaColumns.DISPLAY_NAME, displayName);
    values.put(MediaStore.MediaColumns.MIME_TYPE, mimeType);
    values.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM);

    final ContentResolver resolver = context.getContentResolver();
    Uri uri = null;

    try {
        final Uri contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        uri = resolver.insert(contentUri, values);

        if (uri == null)
            throw new IOException("Failed to create new MediaStore record.");

        try (final OutputStream stream = resolver.openOutputStream(uri)) {
            if (stream == null)
                throw new IOException("Failed to open output stream.");
         
            if (!bitmap.compress(format, 95, stream))
                throw new IOException("Failed to save bitmap.");
        }

        return uri;
    }
    catch (IOException e) {

        if (uri != null) {
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(uri, null, null);
        }

        throw e;
    }
}

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    val resolver = context.contentResolver
    var uri: Uri? = null

    try {
        uri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
            ?: throw IOException("Failed to create new MediaStore record.")

        resolver.openOutputStream(uri)?.use {
            if (!bitmap.compress(format, 95, it))
                throw IOException("Failed to save bitmap.")
        } ?: throw IOException("Failed to open output stream.")

        return uri

    } catch (e: IOException) {

        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(orphanUri, null, null)
        }

        throw e
    }
}

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    var uri: Uri? = null

    return runCatching {
        with(context.contentResolver) {
            insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)?.also {
                uri = it // Keep uri reference so it can be removed on failure

                openOutputStream(it)?.use { stream ->
                    if (!bitmap.compress(format, 95, stream))
                        throw IOException("Failed to save bitmap.")
                } ?: throw IOException("Failed to open output stream.")

            } ?: throw IOException("Failed to create new MediaStore record.")
        }
    }.getOrElse {
        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            context.contentResolver.delete(orphanUri, null, null)
        }

        throw it
    }
}

Kotlin:

@NonNull
public Uri saveBitmap(@NonNull final Context context, @NonNull final Bitmap bitmap,
                      @NonNull final Bitmap.CompressFormat format,
                      @NonNull final String mimeType,
                      @NonNull final String displayName) throws IOException {

    final ContentValues values = new ContentValues();
    values.put(MediaStore.MediaColumns.DISPLAY_NAME, displayName);
    values.put(MediaStore.MediaColumns.MIME_TYPE, mimeType);
    values.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM);

    final ContentResolver resolver = context.getContentResolver();
    Uri uri = null;

    try {
        final Uri contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        uri = resolver.insert(contentUri, values);

        if (uri == null)
            throw new IOException("Failed to create new MediaStore record.");

        try (final OutputStream stream = resolver.openOutputStream(uri)) {
            if (stream == null)
                throw new IOException("Failed to open output stream.");
         
            if (!bitmap.compress(format, 95, stream))
                throw new IOException("Failed to save bitmap.");
        }

        return uri;
    }
    catch (IOException e) {

        if (uri != null) {
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(uri, null, null);
        }

        throw e;
    }
}

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    val resolver = context.contentResolver
    var uri: Uri? = null

    try {
        uri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
            ?: throw IOException("Failed to create new MediaStore record.")

        resolver.openOutputStream(uri)?.use {
            if (!bitmap.compress(format, 95, it))
                throw IOException("Failed to save bitmap.")
        } ?: throw IOException("Failed to open output stream.")

        return uri

    } catch (e: IOException) {

        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(orphanUri, null, null)
        }

        throw e
    }
}

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    var uri: Uri? = null

    return runCatching {
        with(context.contentResolver) {
            insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)?.also {
                uri = it // Keep uri reference so it can be removed on failure

                openOutputStream(it)?.use { stream ->
                    if (!bitmap.compress(format, 95, stream))
                        throw IOException("Failed to save bitmap.")
                } ?: throw IOException("Failed to open output stream.")

            } ?: throw IOException("Failed to create new MediaStore record.")
        }
    }.getOrElse {
        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            context.contentResolver.delete(orphanUri, null, null)
        }

        throw it
    }
}

Kotlin变体，功能性更强：

@NonNull
public Uri saveBitmap(@NonNull final Context context, @NonNull final Bitmap bitmap,
                      @NonNull final Bitmap.CompressFormat format,
                      @NonNull final String mimeType,
                      @NonNull final String displayName) throws IOException {

    final ContentValues values = new ContentValues();
    values.put(MediaStore.MediaColumns.DISPLAY_NAME, displayName);
    values.put(MediaStore.MediaColumns.MIME_TYPE, mimeType);
    values.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM);

    final ContentResolver resolver = context.getContentResolver();
    Uri uri = null;

    try {
        final Uri contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        uri = resolver.insert(contentUri, values);

        if (uri == null)
            throw new IOException("Failed to create new MediaStore record.");

        try (final OutputStream stream = resolver.openOutputStream(uri)) {
            if (stream == null)
                throw new IOException("Failed to open output stream.");
         
            if (!bitmap.compress(format, 95, stream))
                throw new IOException("Failed to save bitmap.");
        }

        return uri;
    }
    catch (IOException e) {

        if (uri != null) {
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(uri, null, null);
        }

        throw e;
    }
}

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    val resolver = context.contentResolver
    var uri: Uri? = null

    try {
        uri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
            ?: throw IOException("Failed to create new MediaStore record.")

        resolver.openOutputStream(uri)?.use {
            if (!bitmap.compress(format, 95, it))
                throw IOException("Failed to save bitmap.")
        } ?: throw IOException("Failed to open output stream.")

        return uri

    } catch (e: IOException) {

        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            resolver.delete(orphanUri, null, null)
        }

        throw e
    }
}

@Throws(IOException::class)
fun saveBitmap(
    context: Context, bitmap: Bitmap, format: Bitmap.CompressFormat,
    mimeType: String, displayName: String
): Uri {

    val values = ContentValues().apply {
        put(MediaStore.MediaColumns.DISPLAY_NAME, displayName)
        put(MediaStore.MediaColumns.MIME_TYPE, mimeType)
        put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_DCIM)
    }

    var uri: Uri? = null

    return runCatching {
        with(context.contentResolver) {
            insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)?.also {
                uri = it // Keep uri reference so it can be removed on failure

                openOutputStream(it)?.use { stream ->
                    if (!bitmap.compress(format, 95, stream))
                        throw IOException("Failed to save bitmap.")
                } ?: throw IOException("Failed to open output stream.")

            } ?: throw IOException("Failed to create new MediaStore record.")
        }
    }.getOrElse {
        uri?.let { orphanUri ->
            // Don't leave an orphan entry in the MediaStore
            context.contentResolver.delete(orphanUri, null, null)
        }

        throw it
    }
}

图像将存储在根级别的图片文件夹中

---

请参见我创建的实时教程

这是我经常使用的。你可以试试

 private void saveImageToStorage() throws IOException {

    OutputStream imageOutStream;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {

        ContentValues values = new ContentValues();
        values.put(MediaStore.Images.Media.DISPLAY_NAME, "image_screenshot.jpg");
        values.put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg");
        values.put(MediaStore.Images.Media.RELATIVE_PATH, Environment.DIRECTORY_PICTURES);
        Uri uri = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);

        imageOutStream = getContentResolver().openOutputStream(uri);
    } else {
        String imagePath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString();
        File image = new File(imagePath, "image_screenshotjpg");
        imageOutStream = new FileOutputStream(image);
    }

    try {
        bitmapObject.compress(Bitmap.CompressFormat.JPEG, 100, imageOutStream);
    } finally {
        imageOutStream.close();
    }

}

---

如果有人正在研究如何将照片保存到DCIM文件夹中，其方式将在以后的Google照片中出现： （根据：）

ContentValue=newcontentvalues（）；
value.put（MediaStore.MediaColumns.RELATIVE_PATH，Environment.DIRECTORY_DCIM）；
value.put（MediaStore.MediaColumns.DATE_take，System.currentTimeMillis（））；
value.put（MediaStore.MediaColumns.IS_PENDING，true）；
Uri=context.getContentResolver（）.insert（externalContentUri，值）；
if（uri！=null）{
试一试{
if（WriteFileToStream（原始文件，context.getContentResolver（）.openOutputStream（uri）））{
value.put（MediaStore.MediaColumns.IS_PENDING，false）；
context.getContentResolver（）.update（uri，value，null，null）；
}
}捕获（例外e）{
getContentResolver（）.delete（uri，null，null）；
}
}

---

其中，

WriteFileToStream

是从文件复制到流的标准方法。

非常感谢，这确实有帮助，但还有3点。请检查我编辑的问题：这个问题是仅在Android Q中发生，还是在所有Android版本中发生？考虑到我的答案中的代码是针对Android Q的。对于旧版本的Android，你需要像往常一样创建path+文件。哦，这是在Android Pie而不是Q上测试的。所以我应该做的是检查Android版本，如果是Q，则执行上面的代码，如果是较低的，则使用通常不推荐的代码？是的，对于早于Q的代码，您需要使用原始代码。您的代码已弃用，但在旧版本中有效。您必须使用

File.separator

，而不是

pathsparator

。我提交了一个编辑，但奇怪的是，OP不理解并拒绝了它。请看，在我添加之前，我还在文件名中获取这些随机数：

put（MediaStore.MediaColumns.DISPLAY_name，name+“.mp3”）

但如何检查图像是否已保存！没人谈论它！您可以使用以下代码检查exist文件：

if（isFilePresent（））{//call save function here}else{//Toast file exist/}private boolean isFilePresent（）{file file file file=new file（Environment.getExternalStoragePublicDirectory（Environment.DIRECTORY_PICTURES），name+“.jpg”）；return file.exists（）；}

@RachitVohera您的回答是正确的，但您之前的评论不是-

getExternalStoragePublicDirectory

在Android 10中不推荐使用。这就是为什么要使用

if（Build.VERSION.SDK\u INT>=Build.VERSION\u CODES.Q）{

在你的回答中。嘿，如果我想用一个intent打开这个图片库怎么办？我传递了内容URI，但仍然没有找到文件运行媒体扫描以添加新媒体我尝试使用这种方法，但是，我得到了

IllegalArgumentException:找不到包含/Pictures/2020-12-17170659úphoto的配置根目录.jpg

当我在Android Q上保存文件后立即尝试

FileProvider.getUriForFile（）

时。在清单中，FileProvider

provider

已正确设置。在使用MediaStore时，保存后是否无法获取Uri（插入表中）？可能需要使用GetExternalFileDir（）保存我的图像，然后调用

FileProvider.getUriForFile（）

？