今天就跟大家聊聊有关如何在Android中使用生命周期架构组件,可能很多人都不太了解,为了让大家更加了解,小编给大家总结了以下内容,希望大家根据这篇文章可以有所收获。
Support Library 26.1+ 直接支持生命周期架构组件。使用该组件,Android 生命周期的梦魇已经成为过去。再也不用担心出现 Can not perform this action after onSaveInstanceState 这样的异常了。
public class LifecycleDelegate implements LifecycleObserver {
private LinkedList<Runnable> tasks = new LinkedList<>();
private final LifecycleOwner lifecycleOwner;
public LifecycleDelegate(LifecycleOwner lifecycleOwner) {
this.lifecycleOwner = lifecycleOwner;
lifecycleOwner.getLifecycle().addObserver(this);
}
public void scheduleTaskAtStarted(Runnable runnable) {
if (getLifecycle().getCurrentState() != Lifecycle.State.DESTROYED) {
assertMainThread();
tasks.add(runnable);
considerExecute();
}
}
@OnLifecycleEvent(Lifecycle.Event.ON_ANY)
void onStateChange() {
if (getLifecycle().getCurrentState() == Lifecycle.State.DESTROYED) {
tasks.clear();
getLifecycle().removeObserver(this);
} else {
considerExecute();
}
}
void considerExecute() {
if (isAtLeastStarted()) {
for (Runnable task : tasks) {
task.run();
}
tasks.clear();
}
}
boolean isAtLeastStarted() {
return getLifecycle().getCurrentState().isAtLeast(Lifecycle.State.STARTED);
}
private Lifecycle getLifecycle() {
return lifecycleOwner.getLifecycle();
}
private void assertMainThread() {
if (!isMainThread()) {
throw new IllegalStateException("you should perform the task at main thread.");
}
}
static boolean isMainThread() {
return Looper.getMainLooper().getThread() == Thread.currentThread();
}
}
在 Activity 或 Fragment 中这样使用
private LifecycleDelegate lifecycleDelegate = new LifecycleDelegate(this);
然后在适当的时机调用 lifecycleDelegate.scheduleTaskAtStarted
该辅助类会检查是否在主线程调用,以确保线程安全以及在主线程更新 UI。
看完上述内容,你们对如何在Android中使用生命周期架构组件有进一步的了解吗?如果还想了解更多知识或者相关内容,请关注天达云行业资讯频道,感谢大家的支持。