class: VariantDict

[44:7] extends: object

#GVariantDict is a mutable interface to #GVariant dictionaries. It can be used for doing a sequence of dictionary lookups in an efficient way on an existing #GVariant dictionary or it can be used to construct new dictionaries with a hashtable-like interface. It can also be used for taking existing dictionaries and modifying them in order to create new ones. #GVariantDict can only be used with %G_VARIANT_TYPE_VARDICT dictionaries. It is possible to use #GVariantDict allocated on the stack or on the heap. When using a stack-allocated #GVariantDict, you begin with a call to g_variant_dict_init() and free the resources with a call to g_variant_dict_clear(). Heap-allocated #GVariantDict follows normal refcounting rules: you allocate it with g_variant_dict_new() and use g_variant_dict_ref() and g_variant_dict_unref(). g_variant_dict_end() is used to convert the #GVariantDict back into a dictionary-type #GVariant. When used with stack-allocated instances, this also implicitly frees all associated memory, but for heap-allocated instances, you must still call g_variant_dict_unref() afterwards. You will typically want to use a heap-allocated #GVariantDict when you expose it as part of an API. For most other uses, the stack-allocated form will be more convenient. Consider the following two examples that do the same thing in each style: take an existing dictionary and look up the "count" uint32 key, adding 1 to it if it is found, or returning an error if the key is not found. Each returns the new dictionary as a floating #GVariant. ## Using a stack-allocated GVariantDict |[ GVariant * add_to_count (GVariant *orig, GError **error) { GVariantDict dict; guint32 count; g_variant_dict_init (&dict, orig); if (!g_variant_dict_lookup (&dict, "count", "u", &count)) { g_set_error (...); g_variant_dict_clear (&dict); return NULL; } g_variant_dict_insert (&dict, "count", "u", count + 1); return g_variant_dict_end (&dict); } ]| ## Using heap-allocated GVariantDict |[ GVariant * add_to_count (GVariant *orig, GError **error) { GVariantDict *dict; GVariant *result; guint32 count; dict = g_variant_dict_new (orig); if (g_variant_dict_lookup (dict, "count", "u", &count)) { g_variant_dict_insert (dict, "count", "u", count + 1); result = g_variant_dict_end (dict); } else { g_set_error (...); result = NULL; } g_variant_dict_unref (dict); return result; } ]|

Members

• handleObj
• lib
• retainedCallbacks
• signalHandlerNames
• signalSetterHandlers

Methods

• VariantDict (Handle = null)

  Creates a new VariantDict by wrapping a native handle or another wrapper.

  • @p Handle is the native handle or another wrapper whose handle to adopt.

• toNativeHandle (Source)

  Normalizes a constructor argument into a raw pointer carrier. Accepts a raw NativeHandle, a raw NativeBuffer returned from fn.call(...), another generated wrapper exposing handle(), or null. Returns null when the argument carries no pointer.

  • @p Source is the raw handle, raw buffer, wrapper, or null.
  • @r A raw pointer carrier or null when no pointer is present.

• getLib ()

  Returns the opened native library for this generated wrapper.

  • @r The opened native library.

• handle ()

  Returns the wrapped NativeHandle.

  • @r The wrapped NativeHandle.

• isNull ()

  Returns true when the wrapped handle is null.

  • @r A bool.

• describe ()

  Returns a small string for debugging generated wrappers.

  • @r A string.