【Android 插件化】Hook 插件化框架 ( 从 Hook 应用角度分析 Activity 启动流程 二 | AMS 进程相关源码 | 主进程相关源码 )（三）

/**
     * Start pausing the currently resumed activity.  It is an error to call this if there
     * is already an activity being paused or there is no resumed activity.
     *
     * @param userLeaving True if this should result in an onUserLeaving to the current activity.
     * @param uiSleeping True if this is happening with the user interface going to sleep (the
     * screen turning off).
     * @param resuming The activity we are currently trying to resume or null if this is not being
     *                 called as part of resuming the top activity, so we shouldn't try to instigate
     *                 a resume here if not null.
     * @param pauseImmediately True if the caller does not want to wait for the activity callback to
     *                         complete pausing.
     * @return Returns true if an activity now is in the PAUSING state, and we are waiting for
     * it to tell us when it is done.
     */
    final boolean startPausingLocked(boolean userLeaving, boolean uiSleeping,
            ActivityRecord resuming, boolean pauseImmediately) {
                mService.getLifecycleManager().scheduleTransaction(prev.app.thread, prev.appToken,
                        PauseActivityItem.obtain(prev.finishing, userLeaving,
                                prev.configChangeFlags, pauseImmediately));
  }

private static final String TAG = "PauseActivityItem";
    private boolean mFinished;
    private boolean mUserLeaving;
    private int mConfigChanges;
    private boolean mDontReport;
    @Override
    public void execute(ClientTransactionHandler client, IBinder token,
            PendingTransactionActions pendingActions) {
        Trace.traceBegin(TRACE_TAG_ACTIVITY_MANAGER, "activityPause");
        client.handlePauseActivity(token, mFinished, mUserLeaving, mConfigChanges, pendingActions,
                "PAUSE_ACTIVITY_ITEM");
        Trace.traceEnd(TRACE_TAG_ACTIVITY_MANAGER);
    }
}

class ActivityStack<T extends StackWindowController> extends ConfigurationContainer
        implements StackWindowListener {
    /** Run all ActivityStacks through this */
    protected final ActivityStackSupervisor mStackSupervisor;
    @GuardedBy("mService")
    private boolean resumeTopActivityInnerLocked(ActivityRecord prev, ActivityOptions options) {
        if (mResumedActivity != null) {
            if (DEBUG_STATES) Slog.d(TAG_STATES,
                    "resumeTopActivityLocked: Pausing " + mResumedActivity);
            pausing |= startPausingLocked(userLeaving, false, next, false);
        }
  mStackSupervisor.startSpecificActivityLocked(next, true, false);
  }
}

void startSpecificActivityLocked(ActivityRecord r,
            boolean andResume, boolean checkConfig) {
                realStartActivityLocked(r, app, andResume, checkConfig);
    }
    final boolean realStartActivityLocked(ActivityRecord r, ProcessRecord app,
            boolean andResume, boolean checkConfig) throws RemoteException {
                // Create activity launch transaction.
                final ClientTransaction clientTransaction = ClientTransaction.obtain(app.thread,
                        r.appToken);
                clientTransaction.addCallback(LaunchActivityItem.obtain(new Intent(r.intent),
                        System.identityHashCode(r), r.info,
                        // TODO: Have this take the merged configuration instead of separate global
                        // and override configs.
                        mergedConfiguration.getGlobalConfiguration(),
                        mergedConfiguration.getOverrideConfiguration(), r.compat,
                        r.launchedFromPackage, task.voiceInteractor, app.repProcState, r.icicle,
                        r.persistentState, results, newIntents, mService.isNextTransitionForward(),
                        profilerInfo));  
  }

public class LaunchActivityItem extends ClientTransactionItem {
    @Override
    public void execute(ClientTransactionHandler client, IBinder token,
            PendingTransactionActions pendingActions) {
        Trace.traceBegin(TRACE_TAG_ACTIVITY_MANAGER, "activityStart");
        ActivityClientRecord r = new ActivityClientRecord(token, mIntent, mIdent, mInfo,
                mOverrideConfig, mCompatInfo, mReferrer, mVoiceInteractor, mState, mPersistentState,
                mPendingResults, mPendingNewIntents, mIsForward,
                mProfilerInfo, client);
        client.handleLaunchActivity(r, pendingActions, null /* customIntent */);
        Trace.traceEnd(TRACE_TAG_ACTIVITY_MANAGER);
    }
}

/**
     * Extended implementation of activity launch. Used when server requests a launch or relaunch.
     */
    @Override
    public Activity handleLaunchActivity(ActivityClientRecord r,
            PendingTransactionActions pendingActions, Intent customIntent) {
        // If we are getting ready to gc after going to the background, well
        // we are back active so skip it.
        unscheduleGcIdler();
        mSomeActivitiesChanged = true;
        if (r.profilerInfo != null) {
            mProfiler.setProfiler(r.profilerInfo);
            mProfiler.startProfiling();
        }
        // Make sure we are running with the most recent config.
        handleConfigurationChanged(null, null);
        if (localLOGV) Slog.v(
            TAG, "Handling launch of " + r);
        // Initialize before creating the activity
        if (!ThreadedRenderer.sRendererDisabled) {
            GraphicsEnvironment.earlyInitEGL();
        }
        WindowManagerGlobal.initialize();
        final Activity a = performLaunchActivity(r, customIntent);
        if (a != null) {
            r.createdConfig = new Configuration(mConfiguration);
            reportSizeConfigurations(r);
            if (!r.activity.mFinished && pendingActions != null) {
                pendingActions.setOldState(r.state);
                pendingActions.setRestoreInstanceState(true);
                pendingActions.setCallOnPostCreate(true);
            }
        } else {
            // If there was an error, for any reason, tell the activity manager to stop us.
            try {
                ActivityManager.getService()
                        .finishActivity(r.token, Activity.RESULT_CANCELED, null,
                                Activity.DONT_FINISH_TASK_WITH_ACTIVITY);
            } catch (RemoteException ex) {
                throw ex.rethrowFromSystemServer();
            }
        }
        return a;
    }

public final class ActivityThread extends ClientTransactionHandler {
    /**  Core implementation of activity launch. */
    private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {
        ActivityInfo aInfo = r.activityInfo;
  activity = mInstrumentation.newActivity(
                      cl, component.getClassName(), r.intent);
  }
}