public void FromCamera() {

    Log.i("camera", "startCameraActivity()");
    File file = new File(path);
    Uri outputFileUri = Uri.fromFile(file);
    Intent intent = new Intent(
            android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
    intent.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);
    startActivityForResult(intent, 1);

}

public void FromCard() {
    Intent i = new Intent(Intent.ACTION_PICK,
            android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
    startActivityForResult(i, 2);
}

 protected void onActivityResult(int requestCode, int resultCode, Intent data) {

    super.onActivityResult(requestCode, resultCode, data);

    if (requestCode == 2 && resultCode == RESULT_OK
            && null != data) {

        Uri selectedImage = data.getData();
        String[] filePathColumn = { MediaStore.Images.Media.DATA };

        Cursor cursor = getContentResolver().query(selectedImage,
                filePathColumn, null, null, null);
        cursor.moveToFirst();

        int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
        String picturePath = cursor.getString(columnIndex);
        cursor.close();

        bitmap = BitmapFactory.decodeFile(picturePath);
        image.setImageBitmap(bitmap);

        if (bitmap != null) {
            ImageView rotate = (ImageView) findViewById(R.id.rotate);

        }

    } else {

        Log.i("SonaSys", "resultCode: " + resultCode);
        switch (resultCode) {
        case 0:
            Log.i("SonaSys", "User cancelled");
            break;
        case -1:
            onPhotoTaken();
            break;

        }

    }

}

protected void onPhotoTaken() {
    // Log message
    Log.i("SonaSys", "onPhotoTaken");
    taken = true;
    imgCapFlag = true;
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inSampleSize = 4;
    bitmap = BitmapFactory.decodeFile(path, options);
    image.setImageBitmap(bitmap);


}

这是一个完整的示例请求权限(如果需要)，从图库中选择图像，然后将图像转换为位图或文件

AndroidManifesh.xml

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

活动

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        button_pick_image.setOnClickListener {
            pickImage()
        }
    }

    private fun pickImage() {
        if (ActivityCompat.checkSelfPermission(this, READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
            val intent = Intent(
                Intent.ACTION_PICK,
                MediaStore.Images.Media.INTERNAL_CONTENT_URI
            )
            intent.type = "image/*"
            intent.putExtra("crop", "true")
            intent.putExtra("scale", true)
            intent.putExtra("aspectX", 16)
            intent.putExtra("aspectY", 9)
            startActivityForResult(intent, PICK_IMAGE_REQUEST_CODE)
        } else {
            ActivityCompat.requestPermissions(
                this,
                arrayOf(Manifest.permission.READ_EXTERNAL_STORAGE),
                READ_EXTERNAL_STORAGE_REQUEST_CODE
            )
        }
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (requestCode == PICK_IMAGE_REQUEST_CODE) {
            if (resultCode != Activity.RESULT_OK) {
                return
            }
            val uri = data?.data
            if (uri != null) {
                val imageFile = uriToImageFile(uri)
                // todo do something with file
            }
            if (uri != null) {
                val imageBitmap = uriToBitmap(uri)
                // todo do something with bitmap
            }
        }
    }

    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        when (requestCode) {
            READ_EXTERNAL_STORAGE_REQUEST_CODE -> {
                if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    // pick image after request permission success
                    pickImage()
                }
            }
        }
    }

    private fun uriToImageFile(uri: Uri): File? {
        val filePathColumn = arrayOf(MediaStore.Images.Media.DATA)
        val cursor = contentResolver.query(uri, filePathColumn, null, null, null)
        if (cursor != null) {
            if (cursor.moveToFirst()) {
                val columnIndex = cursor.getColumnIndex(filePathColumn[0])
                val filePath = cursor.getString(columnIndex)
                cursor.close()
                return File(filePath)
            }
            cursor.close()
        }
        return null
    }

    private fun uriToBitmap(uri: Uri): Bitmap {
        return MediaStore.Images.Media.getBitmap(this.contentResolver, uri)
    }

    companion object {
        const val PICK_IMAGE_REQUEST_CODE = 1000
        const val READ_EXTERNAL_STORAGE_REQUEST_CODE = 1001
    }
}

演示 https://github.com/PhanVanLinh/AndroidPickImage

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/*")
        }
    }
}

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/*")
    }
}

由于startActivityForResult()已经废弃，我们可以使用ActivityResultLauncher以以下方式从图库中选择图像:

首先，我们需要定义一个ActivityResultLauncher<String[]>并在onCreate()(用于活动)或onViewCreated()(用于片段)中初始化它

        ActivityResultLauncher<String[]> galleryActivityLauncher = registerForActivityResult(new ActivityResultContracts.OpenDocument(), new ActivityResultCallback<Uri>() {
            @Override
            public void onActivityResult(Uri result) {
                if (result != null) {
                    // perform desired operations using the result Uri
                } else {
                    Log.d(TAG, "onActivityResult: the result is null for some reason");
                }
            }
        });

假设我们需要在点击submitButton时打开图库。

在onClickListener中，我们需要调用

galleryActivityLauncher.launch(new String[]{"image/*"});

这里的技巧是launch()的参数。通过在参数数组中添加"image/*"，我们指定文件资源管理器只加载图像。

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。