android如何禁止安裝第三方應用

在PackageManagerService.java installPackageLI 函數做處理

private void installPackageLI(InstallArgs args, PackageInstalledInfo res) {
    final int installFlags = args.installFlags;
    final String installerPackageName = args.installerPackageName;
    final String volumeUuid = args.volumeUuid;
    final File tmpPackageFile = new File(args.getCodePath());
    final boolean forwardLocked = ((installFlags & PackageManager.INSTALL_FORWARD_LOCK) != 0);
    final boolean onExternal = (((installFlags & PackageManager.INSTALL_EXTERNAL) != 0)
            || (args.volumeUuid != null));
    final boolean instantApp = ((installFlags & PackageManager.INSTALL_INSTANT_APP) != 0);
    final boolean fullApp = ((installFlags & PackageManager.INSTALL_FULL_APP) != 0);
    final boolean forceSdk = ((installFlags & PackageManager.INSTALL_FORCE_SDK) != 0);
    final boolean virtualPreload =
            ((installFlags & PackageManager.INSTALL_VIRTUAL_PRELOAD) != 0);
    boolean replace = false;
    @ScanFlags int scanFlags = SCAN_NEW_INSTALL | SCAN_UPDATE_SIGNATURE;
    /*meig:jicong.wang add for task 4616 start {@*/
    if (mSystemReady) {
        if (!SystemProperties.getBoolean("persist.sys.installed", false)) {
            res.setReturnCode(PackageManager.INSTALL_FAILED_INVALID_APK);
            return;
        }
    }
    /*meig:jicong.wang add for task 4616 end @}*/

同時添加persist.sys.installed 來控制是否開發安裝app應用。