有时，您无法从所选择的图片中获取文件。 这是因为选择一个来自谷歌+，Drive, Dropbox或任何其他提供商。

最好的解决方案是让系统通过Intent来选择内容。ACTION_GET_CONTENT并使用内容提供程序获取结果。

您可以按照下面的代码或查看我更新的要点。

public void pickImage() {
  Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
  intent.setType("image/*");
  startActivityForResult(intent, PICK_PHOTO_FOR_AVATAR);
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == PICK_PHOTO_FOR_AVATAR && resultCode == Activity.RESULT_OK) {
        if (data == null) {
            //Display an error
            return;
        }
        InputStream inputStream = context.getContentResolver().openInputStream(data.getData());
        //Now you can do whatever you want with your inpustream, save it as file, upload to a server, decode a bitmap...
    }
}

下面是kotlin中util方法的工作代码:

fun launchGalleryWithFragment() {
        val intent = Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI)
        intent.type = "image/*"
        startActivityForResult(Intent.createChooser(intent, "Select Picture"), 1001)
    }

现在重写onActivityResult方法:

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
var path: Uri? = null
        if (requestCode == PICK_IMAGE_REQUEST && resultCode == Activity.RESULT_OK) {
            if(dataIntent == null || dataIntent.data == null){
                return null
            }
            path = dataIntent.data
        }

}

感谢mklkj。

这是一个活动版本。

fileChooserContract可以选择一个图像。 filesChooserContract可以选择多张图片。

class MainActivity : AppCompatActivity() {

    companion object {
        private const val TAG = "MainActivity"
    }

    lateinit var viewBinding: ActivityMainBinding

    private val fileChooserContract = registerForActivityResult(ActivityResultContracts.GetContent()) { uri ->
        Log.d(TAG, "onActivityResult: uri $uri")
    }

    private val filesChooserContract = registerForActivityResult(ActivityResultContracts.GetMultipleContents()) { uriList ->
        for (uri in uriList) {
            Log.d(TAG, "onActivityResult: uri $uri")
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        viewBinding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(viewBinding.root)

        viewBinding.btnPick.setOnClickListener {
            fileChooserContract.launch("image/*")
        }

        viewBinding.btnPickMulti.setOnClickListener {
            filesChooserContract.launch("image/*")
        }
    }
}

如果你只是寻找图像和多重选择。

看一次https://stackoverflow.com/a/15029515/1136023

这对将来很有帮助。我个人觉得使用MultipleImagePick很棒。

对于只从本地选择添加这个:

        i.putExtra(Intent.EXTRA_LOCAL_ONLY,true)

这个工作得很好:

    val i = Intent(Intent.ACTION_GET_CONTENT,MediaStore.Images.Media.EXTERNAL_CONTENT_URI)
    i.type = "image/*"
    i.putExtra(Intent.EXTRA_LOCAL_ONLY,true)
    startActivityForResult(Intent.createChooser(i,"Select Photo"),pickImageRequestCode)

2021 Kotlin解决方案与新版本的Fragment:

dependencies {
  implementation "androidx.fragment:fragment:1.3.3"
}

class YourFragment : Fragment() {

    private val fileChooserContract = registerForActivityResult(ActivityResultContracts.GetContent()) { imageUri ->
        if (imageUri != null) {
            // imageUri now contains URI to selected image
        }
    }

    // ...

    fun openFileChooser() {
        fileChooserContract.launch("image/*")
    }
}