Android应该在异步任务中将片段作为弱引用传递吗

Question

我有下面的片段，它加载了很多数据，这个片段有一个内部静态类，它以以下方式扩展AsyncTask，对片段本身进行弱引用，以防止内存泄漏：

public class PokemonDescriptionFragment extends Fragment {
////////Code
private static class LoadPokemonData extends AsyncTask<Void, Void, Pokemon> {
private WeakReference<PokemonDescriptionFragment> appReference;//FIXME Should I pass fragment as weak reference?
LoadPokemonData(PokemonDescriptionFragment context) {
appReference = new WeakReference<>(context);
}
/**
* Executed before starting the BACKGROUND THREAD
* Executed in the MAIN THREAD
*/
@Override
protected void onPreExecute() {
final PokemonDescriptionFragment fragment = appReference.get();
if (fragment == null) return;
GenericUtils.changeVisibility(View.VISIBLE, fragment.pokedexDataProgressBar, fragment.biologyProgressBar, fragment.statsDataProgressBar, fragment.abilitiesProgressBar, fragment.etymologyProgressBar);
GenericUtils.changeVisibility(View.GONE, fragment.llPokedexContainer);
}
/**
* Executes after onPreExecute.
* Is executed in the BACKGROUND THREAD
* Here you can call "publishProgress" method that executes the "onProgressUpdate" method in Main thread ,
* however , in this case , as I use indeterminated progress bar isn't necessary
*
* @return its sends the values to "onPostExecute"
*/
@Override
protected Pokemon doInBackground(Void... params) {
final PokemonDescriptionFragment fragment = appReference.get();
if (fragment == null) return null;
fragment.initializePokemonData();
return fragment.selectedPokemon;
}
/**
* Executes after doInBackground
* Executed in the MAIN THREAD
*/
@Override
protected void onPostExecute(Pokemon pokemon) {
final PokemonDescriptionFragment fragment = appReference.get();
if (fragment == null) return;
if (Objects.nonNull(pokemon)) {
MainActivity.setSelectedPokemon(pokemon);
fragment.abilityAdapter.refreshAbilities(fragment.abilityList);
}
GenericUtils.changeVisibility(View.GONE, fragment.pokedexDataProgressBar, fragment.biologyProgressBar, fragment.statsDataProgressBar, fragment.abilitiesProgressBar, fragment.etymologyProgressBar);
GenericUtils.changeVisibility(View.VISIBLE, fragment.llPokedexContainer);
fragment.displayFullData();
}
}

然而，我不确定这是否是100%安全的，我将片段作为弱引用传递，因为我需要访问片段所具有的一些方法和属性。此外，如果你检查我的代码，我会声明3次：

final PokemonDescriptionFragment fragment = appReference.get();
if (fragment == null) return null;

在异步任务中，而不是将其声明为异步任务的全局属性并在3个方法中引用它，这是正确的吗？如果我将其添加为Asny任务的全局属性，会有什么问题吗？

Answer 1

在AsyncTask中添加Fragment作为WeakReference是安全的，不应该是内存泄漏的问题。

此外，最好取消碎片onDestroy()中的AsyncTask，以免浪费资源。

但是，考虑完全重构代码，以获得更好的体系结构，从而完全避免在AsyncTask中需要Fragment上下文。