//xml配置<uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES"/>/** * 檢測版本8.0 */public void checkOreo() {  if (SdkVersionUtils.hasOreo()) {//8.0    //判斷是否可以直接安裝    boolean canInstall = getPackageManager().canRequestPackageInstalls();    if (canInstall) {      //rxpermissions請求權限      mRxPermissions          .request(Manifest.permission.REQUEST_INSTALL_PACKAGES)          .subscribe(granted -> {            if (granted) {              //安裝apk              installApk();            } else if (shouldShowRequestPermissionRationale(Manifest.permission.REQUEST_INSTALL_PACKAGES)) {               //引導用戶去打開權限              Intent intent = new Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES);              startActivityForResult(intent, GET_UNKNOWN_APP_SOURCES);            } else {              Intent intent = new Intent(Settings.ACTION_MANAGE_UNKNOWN_APP_SOURCES);              startActivityForResult(intent, GET_UNKNOWN_APP_SOURCES);            }          });    } else {      //安裝apk      installApk();    }  } else {    //安裝apk    installApk()  }}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {  super.onActivityResult(requestCode, resultCode, data);  switch (requestCode) {    case GET_UNKNOWN_APP_SOURCES:      checkOreo();      break;  }}