C++ MenuItem::SetHelpText方法代码示例

static Menu*
add_safe_mode_menu()
{
	Menu* safeMenu = new(nothrow) Menu(SAFE_MODE_MENU, "Safe Mode Options");
	MenuItem* item;

	safeMenu->AddItem(item = new(nothrow) MenuItem("Safe mode"));
	item->SetData(B_SAFEMODE_SAFE_MODE);
	item->SetType(MENU_ITEM_MARKABLE);
	item->SetHelpText("Puts the system into safe mode. This can be enabled "
		"independently from the other options.");

	safeMenu->AddItem(item = new(nothrow) MenuItem("Disable user add-ons"));
	item->SetData(B_SAFEMODE_DISABLE_USER_ADD_ONS);
	item->SetType(MENU_ITEM_MARKABLE);
    item->SetHelpText("Prevents all user installed add-ons from being loaded. "
		"Only the add-ons in the system directory will be used.");

	safeMenu->AddItem(item = new(nothrow) MenuItem("Disable IDE DMA"));
	item->SetData(B_SAFEMODE_DISABLE_IDE_DMA);
	item->SetType(MENU_ITEM_MARKABLE);
    item->SetHelpText("Disables IDE DMA, increasing IDE compatibility "
		"at the expense of performance.");

#if B_HAIKU_PHYSICAL_BITS > 32
	// check whether we have memory beyond 4 GB
	bool hasMemoryBeyond4GB = false;
	for (uint32 i = 0; i < gKernelArgs.num_physical_memory_ranges; i++) {
		phys_addr_range& range = gKernelArgs.physical_memory_range[i];
		if (range.start >= (phys_addr_t)1 << 32) {
			hasMemoryBeyond4GB = true;
			break;
		}
	}

	// ... add the menu, if so
	if (hasMemoryBeyond4GB) {
		safeMenu->AddItem(
			item = new(nothrow) MenuItem("Ignore memory beyond 4 GiB"));
		item->SetData(B_SAFEMODE_4_GB_MEMORY_LIMIT);
		item->SetType(MENU_ITEM_MARKABLE);
		item->SetHelpText("Ignores all memory beyond the 4 GiB address limit, "
			"overriding the setting in the kernel settings file.");
	}
#endif

	platform_add_menus(safeMenu);

	safeMenu->AddSeparatorItem();
	safeMenu->AddItem(item = new(nothrow) MenuItem("Return to main menu"));

	return safeMenu;
}

static Menu *
add_boot_volume_menu(Directory *bootVolume)
{
    Menu *menu = new(nothrow) Menu(CHOICE_MENU, "Select Boot Volume");
    MenuItem *item;
    void *cookie;
    int32 count = 0;

    if (gRoot->Open(&cookie, O_RDONLY) == B_OK) {
        Directory *volume;
        while (gRoot->GetNextNode(cookie, (Node **)&volume) == B_OK) {
            // only list bootable volumes
            if (!is_bootable(volume))
                continue;

            char name[B_FILE_NAME_LENGTH];
            if (volume->GetName(name, sizeof(name)) == B_OK) {
                menu->AddItem(item = new(nothrow) MenuItem(name));
                item->SetTarget(user_menu_boot_volume);
                item->SetData(volume);

                if (volume == bootVolume) {
                    item->SetMarked(true);
                    item->Select(true);
                }

                count++;
            }
        }
        gRoot->Close(cookie);
    }

    if (count == 0) {
        // no boot volume found yet
        menu->AddItem(item = new(nothrow) MenuItem("<No boot volume found>"));
        item->SetType(MENU_ITEM_NO_CHOICE);
        item->SetEnabled(false);
    }

    menu->AddSeparatorItem();

    menu->AddItem(item = new(nothrow) MenuItem("Rescan volumes"));
    item->SetHelpText("Please insert a Antares CD-ROM or attach a USB disk - "
                      "depending on your system, you can then boot from them.");
    item->SetType(MENU_ITEM_NO_CHOICE);
    if (count == 0)
        item->Select(true);

    menu->AddItem(item = new(nothrow) MenuItem("Return to main menu"));
    item->SetType(MENU_ITEM_NO_CHOICE);

    if (gKernelArgs.boot_volume.GetBool(BOOT_VOLUME_BOOTED_FROM_IMAGE, false))
        menu->SetChoiceText("CD-ROM or hard drive");

    return menu;
}

void
platform_add_menus(Menu *menu)
{
	MenuItem *item;

	switch (menu->Type()) {
		case MAIN_MENU:
			item = new(std::nothrow)MenuItem("Select video mode", video_mode_menu());
			if (item != NULL) {
				menu->AddItem(item);
				item->SetTarget(video_mode_hook);
				item->SetShortcut('v');
			}

			break;

		case SAFE_MODE_MENU:
			item = new(std::nothrow) MenuItem("Use fail-safe graphics driver");
			if (item != NULL) {
				menu->AddItem(item);
				item->SetType(MENU_ITEM_MARKABLE);
				item->SetData(B_SAFEMODE_FAIL_SAFE_VIDEO_MODE);
				item->SetHelpText("The system will use VESA mode "
					"and won't try to use any video graphics drivers.");
			}

			smp_add_safemode_menus(menu);

			item = new(std::nothrow) MenuItem("Disable ACPI");
			if (item != NULL) {
				menu->AddItem(item);
				item->SetType(MENU_ITEM_MARKABLE);
				item->SetData(B_SAFEMODE_DISABLE_ACPI);
				item->SetHelpText("Disables Advanced Configuration and Power "
					"Interface hardware support, overriding the ACPI setting "
					"in the kernel settings file.");
			}
			break;

		default:
			break;
	}
}

void
platform_add_menus(Menu* menu)
{
	MenuItem* item;

	switch (menu->Type()) {
		case MAIN_MENU:
		case SAFE_MODE_MENU:
			menu->AddItem(item = new(nothrow) MenuItem("A menu item"));
			item->SetType(MENU_ITEM_MARKABLE);
			item->SetData(0);
			item->SetHelpText("A helpful text.");

			menu->AddItem(item = new(nothrow) MenuItem("Another menu item"));
			item->SetHelpText("Some more helpful text.");
			item->SetType(MENU_ITEM_MARKABLE);
			break;
		default:
			break;
	}
}

Menu *
video_mode_menu()
{
	Menu *menu = new(nothrow) Menu(CHOICE_MENU, "Select Video Mode");
	MenuItem *item;

	menu->AddItem(item = new(nothrow) MenuItem("Default"));
	item->SetMarked(true);
	item->Select(true);
	item->SetHelpText("The Default video mode is the one currently configured "
		"in the system. If there is no mode configured yet, a viable mode will "
		"be chosen automatically.");


	menu->AddSeparatorItem();
	menu->AddItem(item = new(nothrow) MenuItem("Return to main menu"));
	item->SetType(MENU_ITEM_NO_CHOICE);

	return menu;
}

static Menu*
add_debug_menu()
{
	Menu* menu = new(std::nothrow) Menu(STANDARD_MENU, "Debug Options");
	MenuItem* item;

#if DEBUG_SPINLOCK_LATENCIES
	item = new(std::nothrow) MenuItem("Disable latency checks");
	if (item != NULL) {
		item->SetType(MENU_ITEM_MARKABLE);
		item->SetData(B_SAFEMODE_DISABLE_LATENCY_CHECK);
		item->SetHelpText("Disables latency check panics.");
		menu->AddItem(item);
	}
#endif

	menu->AddItem(item
		= new(nothrow) MenuItem("Enable serial debug output"));
	item->SetData("serial_debug_output");
	item->SetType(MENU_ITEM_MARKABLE);
	item->SetHelpText("Turns on forwarding the syslog output to the serial "
		"interface (default: 115200, 8N1).");

	menu->AddItem(item
		= new(nothrow) MenuItem("Enable on screen debug output"));
	item->SetData("debug_screen");
	item->SetType(MENU_ITEM_MARKABLE);
	item->SetHelpText("Displays debug output on screen while the system "
		"is booting, instead of the normal boot logo.");

	menu->AddItem(item
		= new(nothrow) MenuItem("Disable on screen paging"));
	item->SetData("disable_onscreen_paging");
	item->SetType(MENU_ITEM_MARKABLE);
	item->SetHelpText("Disables paging when on screen debug output is "
		"enabled.");

	menu->AddItem(item = new(nothrow) MenuItem("Enable debug syslog"));
	item->SetType(MENU_ITEM_MARKABLE);
	item->SetMarked(gKernelArgs.keep_debug_output_buffer);
	item->SetTarget(&debug_menu_toggle_debug_syslog);
    item->SetHelpText("Enables a special in-memory syslog buffer for this "
    	"session that the boot loader will be able to access after rebooting.");

	ring_buffer* syslogBuffer
		= (ring_buffer*)gKernelArgs.debug_output.Pointer();
	bool hasPreviousSyslog
		= syslogBuffer != NULL && ring_buffer_readable(syslogBuffer) > 0;
	if (hasPreviousSyslog) {
		menu->AddItem(item = new(nothrow) MenuItem(
			"Save syslog from previous session during boot"));
		item->SetType(MENU_ITEM_MARKABLE);
		item->SetMarked(gKernelArgs.previous_debug_size);
		item->SetTarget(&debug_menu_toggle_previous_debug_syslog);
		item->SetHelpText("Saves the syslog from the previous Haiku session to "
			"/var/log/previous_syslog when booting.");
	}

	bool currentLogItemVisible = platform_debug_get_log_buffer(NULL) != NULL;
	if (currentLogItemVisible) {
		menu->AddSeparatorItem();
		menu->AddItem(item
			= new(nothrow) MenuItem("Display current boot loader log"));
		item->SetTarget(&debug_menu_display_current_log);
		item->SetType(MENU_ITEM_NO_CHOICE);
		item->SetHelpText(
			"Displays the debug info the boot loader has logged.");
	}

	if (hasPreviousSyslog) {
		if (!currentLogItemVisible)
			menu->AddSeparatorItem();

		menu->AddItem(item
			= new(nothrow) MenuItem("Display syslog from previous session"));
		item->SetTarget(&debug_menu_display_previous_syslog);
		item->SetType(MENU_ITEM_NO_CHOICE);
		item->SetHelpText(
			"Displays the syslog from the previous Haiku session.");

		menu->AddItem(item = new(nothrow) MenuItem(
			"Save syslog from previous session", add_save_debug_syslog_menu()));
		item->SetHelpText("Saves the syslog from the previous Haiku session to "
			"disk. Currently only FAT32 volumes are supported.");
	}

	menu->AddSeparatorItem();
	menu->AddItem(item = new(nothrow) MenuItem(
		"Add advanced debug option"));
	item->SetType(MENU_ITEM_NO_CHOICE);
	item->SetTarget(&debug_menu_add_advanced_option);
	item->SetHelpText(
		"Allows advanced debugging options to be entered directly.");

	menu->AddSeparatorItem();
	menu->AddItem(item = new(nothrow) MenuItem("Return to main menu"));

	return menu;
}