android - 使用 Kotlin 从相机/画廊捕获图像并在 Activity/fragment 中显示

Question

我知道这是一个使用 java 很好地回答的微不足道的问题，但我确信有新的 API 可以使事情变得更容易，例如

val getContent = registerForActivityResult(GetContent()) { uri: Uri? ->
//处理返回的 Uri
}

和

val takePicture = registerForActivityResult(ActivityResultContracts.TakePicture()) { success: Boolean ->
    if (success) {
        // The image was saved into the given Uri -> do something with it
    }
}

val imageUri: Uri = ...
button.setOnClickListener {
    takePicture.launch(imageUri)
}

问:如何使用 kotlin 实现上述问题并为此实现最新的 APIs

PS:如果提供的答案贬值或过时，这个问题仍然有效。

Answer 1

这是我的代码，希望对你有帮助

• 拍照:

  fun takePicture() {
        val root =
               File(Environment.getExternalStorageDirectory(), BuildConfig.APPLICATION_ID + File.separator)
           root.mkdirs()
           val fname = "img_" + System.currentTimeMillis() + ".jpg"
           val sdImageMainDirectory = File(root, fname)
           viewModel.profileImageUri = FileProvider.getUriForFile(requireContext(), context?.applicationContext?.packageName + ".provider", sdImageMainDirectory)
           takePicture.launch(viewModel.profileImageUri)
       }

  val takePicture = registerForActivityResult(ActivityResultContracts.TakePicture()) { success: Boolean ->
       if (success) {
           // The image was saved into the given Uri -> do something with it
             Picasso.get().load(viewModel.profileImageUri).resize(800,800).into(registerImgAvatar)
       }
   }

• 从图书馆中选择

    private val pickImages = registerForActivityResult(ActivityResultContracts.GetContent()){ uri: Uri? ->
            uri?.let { it ->
                // The image was saved into the given Uri -> do something with it
               Picasso.get().load(it).resize(800,800).into(registerImgAvatar)
            }
        }

然后在按下按钮时调用函数:

btnSelectFromGallery.setOnClickListener {
                pickImages.launch("image/*")
            }
btnTakePicture.setOnClickListener {
                takePicture()
            }