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
下面的代码在Kotlin片段中工作,用于检查蓝牙权限。年- 2022年
val intent = intent (BluetoothAdapter.ACTION_REQUEST_ENABLE)
registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
// There are no request codes
val data: Intent? = result.data
bluetoothAdapter.enable()
Toast.makeText(context, "Permission Granted: ", Toast.LENGTH_SHORT).show()
dynamicButton()
}
else{Toast.makeText(context, "You have to enable bluetooth to use this app.", Toast.LENGTH_SHORT).show()}
}.launch(intent)
其他回答
Kotlin版本的@Muntashir阿肯解决方案
class BetterActivityResult<Input, Result> private constructor(
caller : ActivityResultCaller,
contract : ActivityResultContract<Input, Result>,
var onActivityResult : ((Result) -> Unit)?,
) {
private val launcher : ActivityResultLauncher<Input> =
caller.registerForActivityResult(contract) { onActivityResult?.invoke(it) }
/**
* Launch activity, same as [ActivityResultLauncher.launch] except that it
* allows a callback
* executed after receiving a result from the target activity.
*/
/**
* Same as [.launch] with last parameter set to `null`.
*/
@JvmOverloads
fun launch(
input : Input,
onActivityResult : ((Result) -> Unit)? = this.onActivityResult,
) {
this.onActivityResult = onActivityResult
launcher.launch(input)
}
companion object {
/**
* Register activity result using a [ActivityResultContract] and an in-place
* activity result callback like
* the default approach. You can still customise callback using [.launch].
*/
fun <Input, Result> registerForActivityResult(
caller : ActivityResultCaller,
contract : ActivityResultContract<Input, Result>,
onActivityResult : ((Result) -> Unit)?,
) : BetterActivityResult<Input, Result> {
return BetterActivityResult(caller, contract, onActivityResult)
}
/**
* Same as [.registerForActivityResult] except
* the last argument is set to `null`.
*/
fun <Input, Result> registerForActivityResult(
caller : ActivityResultCaller,
contract : ActivityResultContract<Input, Result>,
) : BetterActivityResult<Input, Result> {
return registerForActivityResult(caller, contract, null)
}
/**
* Specialised method for launching new activities.
*/
fun registerActivityForResult(
caller : ActivityResultCaller,
) : BetterActivityResult<Intent, ActivityResult> {
return registerForActivityResult(caller, StartActivityForResult())
}
}
}
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.
另一种方法是分3步完成。(考虑到你有一个startActivityForResult(0和onActivityResult()))
创建一个形式为var resultLauncher的变量:ActivityResultLauncher<Intent> 创建一个私有函数,在其中以这种基本格式初始化resultLauncher
resultLauncher=registerForActivityResult(ActivityResultContracts.StartActivityForResult()){result ->
// copy paste the code from the onActivityResult replacing resultcode to result.resultCode
if(result.resultcode==Activity.Result_OK){
val data=result.data // this data variable is of type intent and you can use it
}else{
//code if you do not get the data
}
}
使用startActivityForResult()返回行,并将其替换为resultLauncher.launch(intent)
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
分享我找到的解决方法
首先,使用registerForActivityResult为结果注册这个活动 这将返回一个类型为ActivityResultLauncher<Intent!> 像这样,
private val getResult =
registerForActivityResult(
ActivityResultContracts.StartActivityForResult()
) {
if (it.resultCode == Activity.RESULT_OK) {
val value = it.data?.getStringExtra("input")
}
}
现在,无论我们想在哪里启动result活动我们都可以使用getresult。launch(intent)