Base64 转换 Bitmap
fun convertBase64ToPic(base64: String): Bitmap? {
var value = base64
if (base64.contains(",")) {
value = base64.split(",")[1]
}
val decode = Base64.decode(value, Base64.DEFAULT)
return BitmapFactory.decodeByteArray(decode, 0, decode.size)
}
Bitmap 保存到本地相册，新建 ImageExt.kt 文件
private const val TAG = "ImageExt"
private val ALBUM_DIR = Environment.DIRECTORY_DCIM
private class OutputFileTaker(var file: File? = null)
/**
* 复制图片文件到相册的Pictures文件夹
*
* @param context 上下文
* @param fileName 文件名。 需要携带后缀
* @param relativePath 相对于Pictures的路径
*/
fun File.copyToAlbum(context: Context, fileName: String, relativePath: String?): Uri? {
if (!this.canRead() || !this.exists()) {
Log.w(TAG, "check: read file error: $this")
return null
}
return this.inputStream().use {
it.saveToAlbum(context, fileName, relativePath)
}
}
/**
* 保存图片Stream到相册的Pictures文件夹
*
* @param context 上下文
* @param fileName 文件名。 需要携带后缀
* @param relativePath 相对于Pictures的路径
*/
fun InputStream.saveToAlbum(context: Context, fileName: String, relativePath: String?): Uri? {
val resolver = context.contentResolver
val outputFile = OutputFileTaker()
val imageUri = resolver.insertMediaImage(fileName, relativePath, outputFile)
if (imageUri == null) {
Log.w(TAG, "insert: error: uri == null")
return null
}
(imageUri.outputStream(resolver) ?: return null).use { output ->
this.use { input ->
input.copyTo(output)
imageUri.finishPending(context, resolver, outputFile.file)
}
}
return imageUri
}
/**
* 保存Bitmap到相册的Pictures文件夹
*
* https://developer.android.google.cn/training/data-storage/shared/media
*
* @param context 上下文
* @param fileName 文件名。 需要携带后缀
* @param relativePath 相对于Pictures的路径
* @param quality 质量
*/
fun Bitmap.saveToAlbum(
context: Context,
fileName: String,
relativePath: String? = null,
quality: Int = 75,
): Uri? {
// 插入图片信息
val resolver = context.contentResolver
val outputFile = OutputFileTaker()
val imageUri = resolver.insertMediaImage(fileName, relativePath, outputFile)
if (imageUri == null) {
Log.w(TAG, "insert: error: uri == null")
return null
}
// 保存图片
(imageUri.outputStream(resolver) ?: return null).use {
val format = fileName.getBitmapFormat()
[email protected](format, quality, it)
imageUri.finishPending(context, resolver, outputFile.file)
}
return imageUri
}
private fun Uri.outputStream(resolver: ContentResolver): OutputStream? {
return try {
resolver.openOutputStream(this)
} catch (e: FileNotFoundException) {
Log.e(TAG, "save: open stream error: $e")
null
}
}
private fun Uri.finishPending(
context: Context,
resolver: ContentResolver,
outputFile: File?,
) {
val imageValues = ContentValues()
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
if (outputFile != null) {
imageValues.put(MediaStore.Images.Media.SIZE, outputFile.length())
}
resolver.update(this, imageValues, null, null)
// 通知媒体库更新
val intent = Intent(@Suppress("DEPRECATION") Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, this)
context.sendBroadcast(intent)
} else {
// Android Q添加了IS_PENDING状态，为0时其他应用才可见
imageValues.put(MediaStore.Images.Media.IS_PENDING, 0)
resolver.update(this, imageValues, null, null)
}
}
private fun String.getBitmapFormat(): Bitmap.CompressFormat {
val fileName = this.lowercase()
return when {
fileName.endsWith(".png") -> Bitmap.CompressFormat.PNG
fileName.endsWith(".jpg") || fileName.endsWith(".jpeg") -> Bitmap.CompressFormat.JPEG
fileName.endsWith(".webp") -> if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R)
Bitmap.CompressFormat.WEBP_LOSSLESS else Bitmap.CompressFormat.WEBP
else -> Bitmap.CompressFormat.PNG
}
}
private fun String.getMimeType(): String? {
val fileName = this.lowercase()
return when {
fileName.endsWith(".png") -> "image/png"
fileName.endsWith(".jpg") || fileName.endsWith(".jpeg") -> "image/jpeg"
fileName.endsWith(".webp") -> "image/webp"
fileName.endsWith(".gif") -> "image/gif"
else -> null
}
}
/**
* 插入图片到媒体库
*/
private fun ContentResolver.insertMediaImage(
fileName: String,
relativePath: String?,
outputFileTaker: OutputFileTaker? = null,
): Uri? {
// 图片信息
val imageValues = ContentValues().apply {
val mimeType = fileName.getMimeType()
if (mimeType != null) {
put(MediaStore.Images.Media.MIME_TYPE, mimeType)
}
val date = System.currentTimeMillis() / 1000
put(MediaStore.Images.Media.DATE_ADDED, date)
put(MediaStore.Images.Media.DATE_MODIFIED, date)
}
// 保存的位置
val collection: Uri
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
val path = if (relativePath != null) "$ALBUM_DIR/${relativePath}" else ALBUM_DIR
imageValues.apply {
put(MediaStore.Images.Media.DISPLAY_NAME, fileName)
put(MediaStore.Images.Media.RELATIVE_PATH, path)
put(MediaStore.Images.Media.IS_PENDING, 1)
}
collection = MediaStore.Images.Media.getContentUri(MediaStore.VOLUME_EXTERNAL_PRIMARY)
// 高版本不用查重直接插入，会自动重命名
} else {
// 老版本
val pictures =
@Suppress("DEPRECATION") Environment.getExternalStoragePublicDirectory(ALBUM_DIR)
val saveDir = if (relativePath != null) File(pictures, relativePath) else pictures
if (!saveDir.exists() && !saveDir.mkdirs()) {
Log.e(TAG, "save: error: can't create Pictures directory")
return null
}
// 文件路径查重，重复的话在文件名后拼接数字
var imageFile = File(saveDir, fileName)
val fileNameWithoutExtension = imageFile.nameWithoutExtension
val fileExtension = imageFile.extension
var queryUri = this.queryMediaImage28(imageFile.absolutePath)
var suffix = 1
while (queryUri != null) {
val newName = fileNameWithoutExtension + "(${suffix++})." + fileExtension
imageFile = File(saveDir, newName)
queryUri = this.queryMediaImage28(imageFile.absolutePath)
}
imageValues.apply {
put(MediaStore.Images.Media.DISPLAY_NAME, imageFile.name)
// 保存路径
val imagePath = imageFile.absolutePath
Log.v(TAG, "save file: $imagePath")
put(@Suppress("DEPRECATION") MediaStore.Images.Media.DATA, imagePath)
}
outputFileTaker?.file = imageFile// 回传文件路径，用于设置文件大小
collection = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
}
// 插入图片信息
return this.insert(collection, imageValues)
}
/**
* Android Q以下版本，查询媒体库中当前路径是否存在
* @return Uri 返回null时说明不存在，可以进行图片插入逻辑
*/
private fun ContentResolver.queryMediaImage28(imagePath: String): Uri? {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) return null
val imageFile = File(imagePath)
if (imageFile.canRead() && imageFile.exists()) {
Log.v(TAG, "query: path: $imagePath exists")
// 文件已存在，返回一个file://xxx的uri
return Uri.fromFile(imageFile)
}
// 保存的位置
val collection = MediaStore.Images.Media.EXTERNAL_CONTENT_URI
// 查询是否已经存在相同图片
val query = this.query(
collection,
arrayOf(MediaStore.Images.Media._ID, @Suppress("DEPRECATION") MediaStore.Images.Media.DATA),
"${@Suppress("DEPRECATION") MediaStore.Images.Media.DATA} == ?",
arrayOf(imagePath), null
)
query?.use {
while (it.moveToNext()) {
val idColumn = it.getColumnIndexOrThrow(MediaStore.Images.Media._ID)
val id = it.getLong(idColumn)
val existsUri = ContentUris.withAppendedId(collection, id)
Log.v(TAG, "query: path: $imagePath exists uri: $existsUri")
return existsUri
}
}
return null
}
用法
val ioResult = withContext(Dispatchers.IO) {
val bitmap = FileUtil.convertBase64ToPic(base64Data)
var result = false
bitmap?.let {
val uri = it.saveToAlbum(context, fileName = "${System.currentTimeMillis()}.png")
result = uri != null
}
result
}
