HarmonyOS 应用运行时报Cannot read property setWindowPrivacyMode of undefined？

Question

如题：HarmonyOS 应用运行时报Cannot read property setWindowPrivacyMode of undefined？

Answer 1

参考示例：

let windowClass: window.Window | undefined = undefined;
windowStage.getMainWindow((err: BusinessError, data) => {
  const errCode: number = err.code;
  if (errCode) {
    console.error(`Failed to obtain the main window. Cause code: ${err.code}, message: ${err.message}`);
    return;
  }
  windowClass = data;
  try {
    let promise = windowClass.setWindowPrivacyMode(true);
    promise.then(() => {
      console.info('Succeeded in setting the brightness.');
    }).catch((err: BusinessError) => {
      console.error(`Failed to set the brightness. Cause code: ${err.code}, message: ${err.message}`);
    });
  } catch (exception) {
    console.error(`Failed to set the brightness. Cause code: ${exception.code}, message: ${exception.message}`);
  }
});