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
似乎onActivityResult在超类中已弃用,但你在你的问题中没有提到超类名称和compileSdkVersion。
在Java和Kotlin中,只要添加@Deprecated,每个类或方法都可以标记为deprecated,所以检查你的超类,你可能扩展了一个错误的类。
当一个类被弃用时,它的所有方法也被弃用。
要看到一个快速的解决方案,点击弃用的方法,并按Ctrl+Q在Android工作室查看方法的文档,应该有一个解决方案。
在我使用androidx和API 29作为compileSdkVersion的项目中,此方法在活动和片段中不弃用
其他回答
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。
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)
如果您正在使用SMS同意API,则使用以下代码(Kotlin):
resultLauncher.launch( consentIntent
)
var resultLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
// There are no request codes
// val data: Intent? = result.data
val message = result.data?.getStringExtra(SmsRetriever.EXTRA_SMS_MESSAGE)
getOtpFromMessage(message)
}
}
dor506回答为我工作,因为我在我的大多数项目中使用BaseActivity,所以对我来说更容易在单个文件中更改代码,而不是我所有的活动。我已经写了这个代码的java版本。
BaseActivity代码:
private int requestCode = -1;
private ActivityResultLauncher<Intent> resultHandler = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mContext = this;
registerForActivityResult();
}
private final void registerForActivityResult() {
if (shouldRegisterForActivityResult()) {
this.resultHandler = registerForActivityResult(new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback() {
public void onActivityResult(Object var1) {
this.onActivityResult((ActivityResult)var1);
}
public final void onActivityResult(ActivityResult result) {
Intrinsics.checkNotNullExpressionValue(result, "result");
AppActivityClass.onActivityResult(result.getData(), AppActivityClass.this.requestCode, result.getResultCode());
AppActivityClass.this.requestCode = -1;
}
});
}
}
public final void startActivityForResult(int requestCode, Intent intent) {
this.requestCode = requestCode;
if (resultHandler != null) {
resultHandler.launch(intent);
}
}
protected static void onActivityResult(Intent intent, int requestCode, int resultCode) {
}
protected Boolean shouldRegisterForActivityResult() {
return false;
}
现在在任何活动中使用这样的代码:
@Override
protected Boolean shouldRegisterForActivityResult() {
return true; // this will override the baseactivity method and we can use onactivityresult
}
private void someMethod(){
Intent i = new Intent(mContext,SomeOtherClassActivity.class);
startActivityForResult(101,i);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 101) {
if (resultCode == RESULT_OK) {
//revert from called class
}
}
}
从现在开始,startActivityForResult()已经被弃用,所以使用new方法代替。
芬兰湾的科特林的例子
fun openActivityForResult() {
startForResult.launch(Intent(this, AnotherActivity::class.java))
}
val startForResult = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) {
result: ActivityResult ->
if (result.resultCode == Activity.RESULT_OK) {
val intent = result.data
// Handle the Intent
//do stuff here
}
}