如何将图像转换为base64并在androidX中使用kotlin对其进行压缩?
我正在创建一个离线短信应用程序。我想知道如何将用户选择的图像转换为字符串base64并对其进行压缩 我搜索了很多资料,但没有找到多少。我找到的所有数据都是Java。但我需要柯特林语 活动文件如何将图像转换为base64并在androidX中使用kotlin对其进行压缩?,android,kotlin,androidx,Android,Kotlin,Androidx,我正在创建一个离线短信应用程序。我想知道如何将用户选择的图像转换为字符串base64并对其进行压缩 我搜索了很多资料,但没有找到多少。我找到的所有数据都是Java。但我需要柯特林语 活动文件 class MainActivity1 :AppCompatActivity(){ private val requestReceiveSms: Int = 1 private val requestSendSms: Int = 2 private var mMessageRecy
class MainActivity1 :AppCompatActivity(){
private val requestReceiveSms: Int = 1
private val requestSendSms: Int = 2
private var mMessageRecycler: RecyclerView? = null
private var mMessageAdapter: MessageAdapter? = null
val SELECT_PICTURE = 5
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
btn1.setOnClickListener {
dispatchGalleryIntent()
}
seupRecycler()
val bundle: Bundle? = intent.extras
bundle?.let {
val NUm = bundle.getString("address")
phone.text = NUm
}
btnSend.setOnClickListener {
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.SEND_SMS) !=
PackageManager.PERMISSION_GRANTED
) {
ActivityCompat.requestPermissions(
this, arrayOf(android.Manifest.permission.SEND_SMS),
requestSendSms
)
} else {
SendSms()
}
}
if(ActivityCompat.checkSelfPermission(this,android.Manifest.permission.RECEIVE_SMS) !=
PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(this, arrayOf(android.Manifest.permission.RECEIVE_SMS),
requestReceiveSms)
}
}
private fun seupRecycler() {
mMessageRecycler = this.reyclerview_message_list as RecyclerView
mMessageAdapter = MessageAdapter(this)
val layoutManager = LinearLayoutManager(this)
layoutManager.orientation = RecyclerView.VERTICAL
}
override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>,
grantResults: IntArray) {
if(requestCode == requestSendSms)SendSms()
}
private fun SendSms() {
val str_address = phone
val str_message = txtMessage.text.toString()
SmsManager.getDefault().sendTextMessage(str_address.toString(),null,str_message,null,null)
Toast.makeText(this,"SMS Sent", Toast.LENGTH_SHORT).show()
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if(requestCode == SELECT_PICTURE && resultCode == Activity.RESULT_OK){
try {
val uri = data!!.data
imageView2.setImageURI(uri)
}catch (e : IOException){
e.printStackTrace()
}
}
}
fun dispatchGalleryIntent(){
val intent = Intent(
Intent.ACTION_PICK,
MediaStore.Images.Media.EXTERNAL_CONTENT_URI)
//intent.type = "image/*"
//intent.action = Intent.ACTION_GET_CONTENT
//startActivityForResult(Intent.createChooser(intent,"SELECT IMAGE"), SELECT_PICTURE)
startActivityForResult(intent,SELECT_PICTURE)
}
}
class MainActivity1:AppCompatActivity(){
private val requestReceiveSms:Int=1
私有val请求发送SMS:Int=2
私有变量mMessageRecycler:RecyclerView?=null
私有变量mMessageAdapter:MessageAdapter?=null
val选择_图片=5
重写创建时的乐趣(savedInstanceState:Bundle?){
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
btn1.setOnClickListener{
调度目录()
}
预循环器()
val bundle:bundle?=intent.extras
捆绑?让我{
val NUm=bundle.getString(“地址”)
phone.text=NUm
}
btnSend.setOnClickListener{
if(ActivityCompat.checkSelfPermission)(这个,android.Manifest.permission.SEND_SMS)=
PackageManager.PERMISSION\u已授予
) {
ActivityCompat.requestPermissions(
这个,arrayOf(android.Manifest.permission.SEND_SMS),
请求发送短信
)
}否则{
SendSms()
}
}
if(ActivityCompat.checkSelfPermission(这个,android.Manifest.permission.RECEIVE_SMS)=
PackageManager.权限(已授予){
ActivityCompat.requestPermissions(这个,arrayOf(android.Manifest.permission.RECEIVE_短信),
requestReceiveSms)
}
}
私家车{
mMessageRecycler=this.reyclerview\u消息\u列表为RecyclerView
mMessageAdapter=MessageAdapter(此)
val layoutManager=LinearLayoutManager(此)
layoutManager.orientation=RecyclerView.VERTICAL
}
重写onRequestPermissionsResult(请求代码:Int,权限:数组,
授予结果:IntArray){
if(requestCode==requestSendSms)SendSms()
}
私人娱乐短信(){
val str_地址=电话
val str_message=txtMessage.text.toString()
SmsManager.getDefault().sendTextMessage(str_address.toString(),null,str_message,null,null)
Toast.makeText(这是“短信发送”,Toast.LENGTH\u SHORT.show())
}
重写activityResult(请求代码:Int,结果代码:Int,数据:Intent?){
super.onActivityResult(请求代码、结果代码、数据)
如果(请求代码==选择图片和结果代码==活动。结果\u确定){
试一试{
val uri=data!!.data
imageView2.setImageURI(uri)
}捕获(e:IOException){
e、 printStackTrace()
}
}
}
娱乐快讯内容(){
val intent=intent(
意向、行动、选择,
MediaStore.Images.Media.EXTERNAL\u CONTENT\u URI)
//intent.type=“image/*”
//intent.action=intent.action\u获取内容
//startActivityForResult(Intent.createChooser(Intent,“选择图像”),选择图片)
startActivityForResult(意图,选择图片)
}
}
预期的
将图像转换为base64并压缩它
实际值
什么也没有发生。如果条件是因为它需要生成版本26。在下面的版本中,它将不起作用
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){
val bm = BitmapFactory.decodeFile("/path/to/image.jpg")
val stream = ByteArrayOutputStream()
bm.compress(CompressFormat.JPEG, 70, stream)
val byteFormat = stream.toByteArray()
val imgString = Base64.getEncoder().encodeToString(byteFormat)
}
要检索路径/到/图像,请执行以下操作:
val uri = data!!.data
val picturePath = getPath(applicationContext, uri) // Write this line under the uri.
Log.d("Picture Path", picturePath)
这是获取图像路径的函数
private fun getPath(applicationContext: Context, uri: Uri?): String? {
var result: String? = null
val proj = arrayOf(MediaStore.Images.Media.DATA)
val cursor = applicationContext.getContentResolver().query(uri, proj, null, null, null)
if (cursor != null) {
if (cursor!!.moveToFirst()) {
val column_index = cursor!!.getColumnIndexOrThrow(proj[0])
result = cursor!!.getString(column_index)
}
cursor!!.close()
}
if (result == null) {
result = "Not found"
}
return result
}
在Kotlin中,将图像文件转换为Base64,然后对其进行压缩
val bm = BitmapFactory.decodeFile("/path/to/image.jpg")
val baos = ByteArrayOutputStream()
bm.compress(Bitmap.CompressFormat.JPEG, 100, baos) //bm is the bitmap object
val b = baos.toByteArray()
val encodedImage = Base64.encodeToString(b, Base64.DEFAULT)
您必须替换第一行中的图像路径。什么是70…?这是质量。压缩机提示,0-100。0表示小尺寸压缩,100表示最高质量压缩。@A您必须向
位图工厂.decodeFile
提供图像位置,该文件类似于您的uri。我想。valuri=data!!。data
`imageView2.setImageURI(uri)`我有这两行您想将图像加载到imageview中吗?它已加载..但我想将该图像转换为base64并压缩它基本上是图像路径造成的问题..通过按照@Ashishcan的说明解决了。请检查此。。?