我最近发现onActivityResult已弃用。我们该怎么处理呢?
有什么替代方案吗?
我最近发现onActivityResult已弃用。我们该怎么处理呢?
有什么替代方案吗?
当前回答
这就是我如何替换多个requestCodes(把这段代码放在你的活动中):
ActivityResultLauncher<Intent> launchCameraActivity = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
@Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
Intent data = result.getData();
Bitmap photoBitmap;
if(data != null && data.getExtras() != null){
photoBitmap = (Bitmap) data.getExtras().get("data");
if (photoBitmap != null) {
dataModel.setPhoto(ImageUtil.convert(photoBitmap));
imageTaken.setVisibility(View.VISIBLE);
imageTaken.setImageBitmap(photoBitmap);
}
}
}
}
});
ActivityResultLauncher<Intent> launchCameraAndGalleryActivity = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
@Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
Intent data = result.getData();
Uri imageUri;
if (data != null) {
imageUri = data.getData();
InputStream imageStream;
try {
imageStream = getContentResolver().openInputStream(imageUri);
Bitmap photoBitmap = BitmapFactory.decodeStream(imageStream);
dataModel.setOtherImage(ImageUtil.convert(photoBitmap));
documentImageTaken.setVisibility(View.VISIBLE);
documentImageTaken.setImageBitmap(photoBitmap);
}catch (FileNotFoundException e) {
e.printStackTrace();
}
}
}
}
});
我是这样开展活动的:
Intent photoIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
launchCameraAndGalleryActivity.launch(photoIntent );
Intent galleryIntent= new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
launchCameraActivity.launch(galleryIntent);
其他回答
onActivityResult, startActivityForResult, requestPermissions和onRequestPermissionsResult从1.3.0-alpha04开始在androidx.fragment上被弃用,android.app.Activity上没有。 相反,你可以使用registerForActivityResult的活动结果api。
参考:Kotlin -从图库中选择图像
迄今为止我发现的最简单的Alernative
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.id.activity_main)
var ivPhoto = findViewById<ImageView>(R.id.ivPhoto)
var btnChoosePhoto = findViewById<Button>(R.id.btnChoosePhoto)
val getContent = registerForActivityResult(ActivityResultContracts.GetContent()) { uri: Uri? ->
ivPhoto.setImageURI(uri) // Handle the returned Uri
}
btnChoose.setOnClickListener {
getContent.launch("image/*")
}
}
startActivityForResult和onActivityResult在android 10 API 30中已弃用,现在我们有了一种新的方法来使用registerForActivityResult来获得结果
resultContract =
registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
// There are no request codes
val country = result.data?.getParcelableExtra<Country>("Country")
showLiveDemoDialogue(country)
}
}
并启动活动
val intent = Intent(this, CountriesListActivity::class.java)
resultContract.launch(intent)
但你应该在呼叫发射前注册然后发射到你想去的任何地方。 否则,您将得到这个异常
attempting to register while current state is RESUMED. LifecycleOwners must call register before they are STARTED.
我使用kotlin扩展,使它非常简单。在你的扩展中添加以下扩展功能。kt文件:
fun AppCompatActivity.startForResult(intent: Intent,
onResult: (resultCode: Int, data: Intent?) -> Unit
) {
this.registerForActivityResult(ActivityResultContracts.StartActivityForResult()) {result ->
onResult(result.resultCode, result.data)
}.launch(intent)
}
现在,在继承AppCompatActivity的任何活动中,你可以使用下面的简单代码:
val i = Intent(this, TargetActivity::class.java)
startForResult(i) { resultCode, data ->
//put your code here like:
if (resultCode == RESULT_OK) {
//your code here...
}
}
}
更新 上述实现可能导致以下异常: java.lang.IllegalStateException: LifecycleOwner xxxx正在尝试注册,而当前状态为恢复。生命周期所有者必须在启动之前调用寄存器。
因此,registerForActivityResult应该提前调用,例如在onCreate之前。这是另一种解决方案。
在你的扩展中添加以下扩展功能。kt文件:
fun AppCompatActivity.registerForResult(onResult: (resultCode: Int, data: Intent?) -> Unit):
ActivityResultLauncher<Intent> {
return this.registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
onResult(result.resultCode, result.data)
}
}
现在,在继承AppCompatActivity的任何活动中,你可以使用下面的简单代码:
为每个需要结果的操作定义一个类成员变量
private val myActionResult = registerForResult { resultCode, data ->
//put your code here like:
if (resultCode == RESULT_OK) {
//your code here...
}
}
}
启动动作
val i = Intent(this, TargetActivity::class.java)
myActionResult.launch(i)
对于那些具有多个requestCode的片段,并且如果您不确定如何处理这些requestCode的多个结果,那么您需要了解requestCode在新方法中是无用的。
我想象你以前的编码方式是这样的:
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (resultCode == Activity.RESULT_CODE) {
when (requestCode) {
REQUEST_TAKE_PHOTO -> {
// handle photo from camera
}
REQUEST_PICK_IMAGE_FROM_GALLERY -> {
// handle image from gallery
}
}
}
}
在新的API中,你需要在一个单独的ActivityResultContract中实现每个请求的结果:
val takePhotoForResult = registerForActivityResult(StartActivityForResult()) { result: ActivityResult ->
if (result.resultCode == Activity.RESULT_OK) {
val intent = result.data
// handle photo from camera
}
}
val pickImageFromGalleryForResult = registerForActivityResult(StartActivityForResult()) { result: ActivityResult ->
if (result.resultCode == Activity.RESULT_OK) {
val intent = result.data
// handle image from gallery
}
}
然后你需要像这样开始这些活动/意图:
private fun startTakePhotoActivity() {
takePhotoForResult.launch(Intent(requireActivity(), TakePhotoActivity::class.java))
}
private fun pickImageFromGallery() {
val pickIntent = Intent(Intent.ACTION_PICK)
pickIntent.setDataAndType(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
"image/*"
)
pickImageFromGalleryForResult.launch(pickIntent)
}
通过这样做,你可以在你的项目中摆脱数百个const val REQUEST_值。