在面试中被问及Glide的来源代码时会涉及哪些知识点？Glide生命周期是如何实现的？

final Map<android.app.FragmentManager, RequestManagerFragment> pendingRequestManagerFragments = new HashMap<>();

private RequestManagerFragment getRequestManagerFragment(@NonNull final android.app.FragmentManager fm, @Nullable android.app.Fragment parentHint, boolean isParentVisible) {

RequestManagerFragment current = (RequestManagerFragment) fm.findFragmentByTag(FRAGMENT_TAG); // 获取Fragment

if (current == null) {

current = pendingRequestManagerFragments.get(fm);

if (current == null) {

current = new RequestManagerFragment();

current.setParentFragmentHint(parentHint);

if (isParentVisibl