避免在設置中強制停止某一應用

音樂播放過程中，在設置-》應用中，對音樂執行強制停止，相關日誌如下：

framework層相關代碼alps\frameworks\base\services\core\java\com\android\server\am\ActivityManagerService.java中對應用停止運行執行的代碼如下：

    @Override
    public void forceStopPackage(final String packageName, int userId) {
        if (checkCallingPermission(android.Manifest.permission.FORCE_STOP_PACKAGES)
                != PackageManager.PERMISSION_GRANTED) {
            String msg = "Permission Denial: forceStopPackage() from pid="
                    + Binder.getCallingPid()
                    + ", uid=" + Binder.getCallingUid()
                    + " requires " + android.Manifest.permission.FORCE_STOP_PACKAGES;
            Slog.w(TAG, msg);
            throw new SecurityException(msg);
        }
        final int callingPid = Binder.getCallingPid();
        userId = mUserController.handleIncomingUser(callingPid, Binder.getCallingUid(),
                userId, true, ALLOW_FULL_ONLY, "forceStopPackage", null);
        long callingId = Binder.clearCallingIdentity();
        try {
            IPackageManager pm = AppGlobals.getPackageManager();
            synchronized(this) {
                int[] users = userId == UserHandle.USER_ALL
                        ? mUserController.getUsers() : new int[] { userId };
                for (int user : users) {
                    int pkgUid = -1;
                    try {
                        pkgUid = pm.getPackageUid(packageName, MATCH_DEBUG_TRIAGED_MISSING,
                                user);
                    } catch (RemoteException e) {
                    }
                    if (pkgUid == -1) {
                        Slog.w(TAG, "Invalid packageName: " + packageName);
                        continue;
                    }
                    try {
                        pm.setPackageStoppedState(packageName, true, user);
                    } catch (RemoteException e) {
                    } catch (IllegalArgumentException e) {
                        Slog.w(TAG, "Failed trying to unstop package "
                                + packageName + ": " + e);
                    }

                    /// M: [process suppression] @{
                    if ("1".equals(SystemProperties.get("persist.runningbooster.support")) ||
                            "1".equals(SystemProperties.get("ro.mtk_aws_support"))) {
                        AMEventHookData.PackageStoppedStatusChanged eventData =
                                AMEventHookData.PackageStoppedStatusChanged.createInstance();
                        eventData.set(packageName, SUPPRESS_ACTION_STOP, "forceStopPackage");
                        mAMEventHook.hook(AMEventHook.Event.AM_PackageStoppedStatusChanged,
                                eventData);
                    }
                    /// M: [process suppression] @}

                    if (mUserController.isUserRunningLocked(user, 0)) {
                        forceStopPackageLocked(packageName, pkgUid, "from pid " + callingPid);
                        finishForceStopPackageLocked(packageName, pkgUid);
                    }
                }
            }
        } finally {
            Binder.restoreCallingIdentity(callingId);
        }
    }

在設置中對音樂點擊強制停止，如果想讓音樂繼續後臺播放，可以在ActivityManagerService.java中對代碼進行控制，判斷packageName是否爲音樂，如果是音樂，直接返回即可。到時產生的效果是，點擊強制停止，會沒有響應，達到了想要的效果。