在画廊 kotlin 上选择照片

Question

如何更改此代码以打开画廊并选择照片。我不需要相机功能。谢谢

我的应用程序中需要此功能，但我无法更改该部分代码。有人可以帮我调整一下。

我根据您指出的修改更新了帖子。

编辑

错误行

val bitmap = MediaStore.Images.Media.getBitmap(context.contentResolver, this.imageUri) as Bitmap

传递结果失败 ResultInfo{who=android:fragment:2, 请求=1000，结果=-1，数据=意图{ dat=content://com.google.android.apps.photos.contentprovider/-1/1/content://media/external/images/media/48/ORIGINAL/NONE/207210023 flg=0x1 剪辑={文本/uri 列表 U:content://com.google.android.apps.photos.contentprovider/-1/1/content%3A%2F%2Fmedia%2Fexternal%2Fimages%2Fmedia%2F48/ORIGINAL/NONE/207210023} }} 到活动 {maps.com/maps.com.MainActivity}： java.lang.NullPointerException: uri

private fun checkPermissionForImage() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if ((checkSelfPermission(this.context, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED)
                    && (checkSelfPermission(this.context, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED)
            ) {
                val permission = arrayOf(Manifest.permission.READ_EXTERNAL_STORAGE)
                val permissionCoarse = arrayOf(Manifest.permission.WRITE_EXTERNAL_STORAGE)

                requestPermissions(permission, PERMISSION_CODE_READ) // GIVE AN INTEGER VALUE FOR PERMISSION_CODE_READ LIKE 1001
                requestPermissions(permissionCoarse, PERMISSION_CODE_WRITE) // GIVE AN INTEGER VALUE FOR PERMISSION_CODE_WRITE LIKE 1002
            } else {
                pickImageFromGallery()
            }
        }
    }
    private fun pickImageFromGallery() {
        val intent = Intent(Intent.ACTION_PICK)
        intent.type = "image/*"
        startActivityForResult(intent, IMAGE_PICK_CODE) // GIVE AN INTEGER VALUE FOR IMAGE_PICK_CODE LIKE 1000
    }

    /**
     * Save the picture to the thumbnail after taking it
     */
    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        if (requestCode == IMAGE_PICK_CODE && resultCode == RESULT_OK) {
            try {
                //Getting the Bitmap from Gallery
                val bitmap = MediaStore.Images.Media.getBitmap(context.contentResolver, this.imageUri) as Bitmap
                this.imgThumb!!.setImageBitmap(bitmap)
                this.pictureTaken = true
            } catch (e:IOException) {
                e.printStackTrace()
            }
        } else {
            Toast.makeText(context, "Error loading image", Toast.LENGTH_LONG)
        }
    }

    @Throws(IOException::class)
    fun createImageFile(): File {
        val timeStamp: String = SimpleDateFormat("yyyyMMdd_HHmmss").format(Date())
        val imageFileName: String = "JPEG_" + timeStamp + "_"
        val storageDir: File = activity.getExternalFilesDir(Environment.DIRECTORY_PICTURES)
        if(!storageDir.exists()) storageDir.mkdirs()
        val imageFile = File.createTempFile(imageFileName, ".jpg", storageDir)
        imageFilePath = imageFile.absolutePath
        return imageFile
    }

Answer 1

首先你必须检查存储权限：

private fun checkPermissionForImage() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if ((checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED)
            && (checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED)
        ) {
            val permission = arrayOf(Manifest.permission.READ_EXTERNAL_STORAGE)
            val permissionCoarse = arrayOf(Manifest.permission.WRITE_EXTERNAL_STORAGE)

            requestPermissions(permission, PERMISSION_CODE_READ) // GIVE AN INTEGER VALUE FOR PERMISSION_CODE_READ LIKE 1001
            requestPermissions(permissionCoarse, PERMISSION_CODE_WRITE) // GIVE AN INTEGER VALUE FOR PERMISSION_CODE_WRITE LIKE 1002
        } else {
            pickImageFromGallery()
        }
    }
}

如您所见，如果授予权限，我正在访问一个名为pickImageFromGallery() 的方法。这是为了访问图库以选择图像：

private fun pickImageFromGallery() {
    val intent = Intent(Intent.ACTION_PICK)
    intent.type = "image/*"
    startActivityForResult(intent, IMAGE_PICK_CODE) // GIVE AN INTEGER VALUE FOR IMAGE_PICK_CODE LIKE 1000
}

现在，您必须重写 onActivityResult 方法。这将返回您选择的图像URI。

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
    if (resultCode == Activity.RESULT_OK && requestCode == IMAGE_PICK_CODE) {
        // I'M GETTING THE URI OF THE IMAGE AS DATA AND SETTING IT TO THE IMAGEVIEW
        imageView.setImageURI(data?.data)
    }
}