HarmonyOS 应用横屏后底部会多出一条系统按钮要如何去掉

可以在EntryAbility的onWindowStageCreate事件中设置以下方案：

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;
  let isLayoutFullScreen = true;
  try {

    windowClass.setWindowLayoutFullScreen(true)
    // 隐藏状态栏显示
    windowClass.setWindowSystemBarEnable(['navigation'])

  } catch (exception) {
    console.error(`Failed to set the window layout to full-screen mode. Cause code: ${exception.code}, message: ${exception.message}`);
  }
})