gtk - 如何在 GLib 对象上设置枚举属性？

Question

我正在尝试在GtkCellRendererText上设置“ellipsize”枚举属性对象。

我尝试按如下方式使用g_object_set_property:

GtkCellRenderer *renderer = gtk_cell_renderer_text_new ();

GValue val = G_VALUE_INIT;
g_value_init (&val, G_TYPE_ENUM);
g_value_set_enum (&val, PANGO_ELLIPSIZE_END);
g_object_set_property (G_OBJECT(renderer), "ellipsize", &val);

但是，我在运行时收到错误消息:

(infog:27114): GLib-GObject-WARNING **: 12:24:29.848: ../../../../gobject/gvalue.c:188: cannot initialize GValue with type 'GEnum', this type is abstract with regards to GValue use, use a more specific (derived) type

如何获取 enum PangoEllipsizeMode 的类型 ID源自 G_TYPE_ENUM？

Answer 1

您需要使用属性所需的枚举类型来初始化 GValue 容器。 G_TYPE_ENUM 是通用的抽象枚举类型。

GtkCellRendererText 的“ellipsize”属性需要一个 PangoEllipsizeMode 枚举值，其 GType 为 PANGO_TYPE_ELLIPSIZE_MODE。

GtkCellRenderer *renderer = gtk_cell_renderer_text_new ();

GValue val = G_VALUE_INIT;

g_value_init (&val, PANGO_TYPE_ELLIPSIZE_MODE);
g_value_set_enum (&val, PANGO_ELLIPSIZE_END);

g_object_set_property (G_OBJECT(renderer), "ellipsize", &val);

// Always unset your value to release any memory that may be associated with it
g_value_unset (&val);