Android开机相关

原创已于 2024-02-18 16:26:37 修改 · 437 阅读

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#android

于 2024-02-02 14:42:49 首次发布

本文详细描述了Android13中对开机广播流程的更新，特别是如何处理deferred接收者，以及BroadcastDispatcher中DeferredBootCompletedBroadcastPerUser的作用，第三方应用需注意对LOCKED_BOOT_COMPLETED和BOOT_COMPLETED的特殊管理。

在这里插入图片描述以上是Android系统广播的流程，从Android13起逻辑上有变更，主要是对Android开机广播做了特殊处理。

    if (Intent.ACTION_LOCKED_BOOT_COMPLETED.equals(r.intent.getAction())) {
        // Create one BroadcastRecord for each UID that can be deferred.
        final SparseArray<BroadcastRecord> deferred =
                r.splitDeferredBootCompletedBroadcastLocked(mQueue.mService.mInternal,
                        mQueue.mService.mConstants.mDeferBootCompletedBroadcast);
        getDeferredPerUser(r.userId).enqueueBootCompletedBroadcasts(
                Intent.ACTION_LOCKED_BOOT_COMPLETED, deferred);
        if (!r.receivers.isEmpty()) {
            // The non-deferred receivers.
            mOrderedBroadcasts.add(r);
            return;
        }
    } else if (Intent.ACTION_BOOT_COMPLETED.equals(r.intent.getAction())) {
        // Create one BroadcastRecord for each UID that can be deferred.
        final SparseArray<BroadcastRecord> deferred =
                r.splitDeferredBootCompletedBroadcastLocked(mQueue.mService.mInternal,
                        mQueue.mService.mConstants.mDeferBootCompletedBroadcast);
        getDeferredPerUser(r.userId).enqueueBootCompletedBroadcasts(
                Intent.ACTION_BOOT_COMPLETED, deferred);
        if (!r.receivers.isEmpty()) {
            // The non-deferred receivers.
            mOrderedBroadcasts.add(r);
            return;
        }
    } else {
        mOrderedBroadcasts.add(r);
    }
}

其中很关键的代码，在特定场景会使用某些开机广播注册者无法收到开机广播：
final SparseArray deferred =
r.splitDeferredBootCompletedBroadcastLocked(mQueue.mService.mInternal,
mQueue.mService.mConstants.mDeferBootCompletedBroadcast);
getDeferredPerUser(r.userId).enqueueBootCompletedBroadcasts(
Intent.ACTION_BOOT_COMPLETED, deferred);

追踪mDeferBootCompletedBroadcast可知默认情况下后台及targetSdkVersion is T的开机广播接收者将会归为延时接收。

BroadcastDisppatcher中新增一个DeferredBootCompletedBroadcastPerUser，管理延时LOCKED_BOOT_COMPLETED，BOOT_COMPLETED的接收者。对于一个第三方应用中注册的开机广播往往会有这里做特殊处理，存放在SparseArray mDeferredBootCompletedBroadcasts = new SparseArray<>()，后续也是从此取出。