ActivityThread$H.md

//9.0.0 之前
class ActivityThread{
    final ArrayMap<IBinder, ActivityClientRecord> mActivities = new ArrayMap<>();
    
    //...
    class H extends Handler{
        //...
        public void handleMessage(Message msg) {
            if (DEBUG_MESSAGES) Slog.v(TAG, ">>> handling: " + codeToString(msg.what));
            switch (msg.what) {
                //...
               case DESTROY_ACTIVITY://109
                    Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "activityDestroy");
                    handleDestroyActivity((IBinder)msg.obj, msg.arg1 != 0, msg.arg2, false);
                    Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
                    break;
                //...
            }
            Object obj = msg.obj;
            if (obj instanceof SomeArgs) {
                ((SomeArgs) obj).recycle();
            }
            if (DEBUG_MESSAGES) Slog.v(TAG, "<<< done: " + codeToString(msg.what));
        }
    }
    
    // 执行onDestroy的方法
    private ActivityClientRecord performDestroyActivity(IBinder token, boolean finishing,int configChanges, boolean getNonConfigInstance) {
        ActivityClientRecord r = mActivities.get(token);
          if (r != null) {
            if (finishing) {
                r.activity.mFinished = true;
            }
            if (!r.stopped) {
                try {
                    r.activity.performStop(r.mPreserveWindow);
                } catch (SuperNotCalledException e) {
                    throw e;
                } catch (Exception e) {
                    if (!mInstrumentation.onException(r.activity, e)) {
                        throw new RuntimeException(
                                "Unable to stop activity "
                                + safeToComponentShortString(r.intent)
                                + ": " + e.toString(), e);
                    }
                }
                r.stopped = true;
                EventLog.writeEvent(LOG_AM_ON_STOP_CALLED, UserHandle.myUserId(),
                        r.activity.getComponentName().getClassName(), "destroy");
            }
            //...
          }
    }
}

//9.0.0 之后
class ActivityThread{
    //...
    class H extends Handler{
        //...
        public void handleMessage(Message msg) {
            if (DEBUG_MESSAGES) Slog.v(TAG, ">>> handling: " + codeToString(msg.what));
            switch (msg.what) {
                //...
                case EXECUTE_TRANSACTION: // 159
                    final ClientTransaction transaction = (ClientTransaction) msg.obj;
                    mTransactionExecutor.execute(transaction);
                    if (isSystem()) {
                        // Client transactions inside system process are recycled on the client side
                        // instead of ClientLifecycleManager to avoid being cleared before this
                        // message is handled.
                        transaction.recycle();
                    }
                    // TODO(lifecycler): Recycle locally scheduled transactions.
                    break;
                //...
            }
            Object obj = msg.obj;
            if (obj instanceof SomeArgs) {
                ((SomeArgs) obj).recycle();
            }
            if (DEBUG_MESSAGES) Slog.v(TAG, "<<< done: " + codeToString(msg.what));
        }
    }
}