gtk2/docs/reference/gtk/text_widget.sgml

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<?xml version="1.0"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN"
"http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd" [
]>
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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<refentry id="TextWidget" revision="18 Oct 2000">
<refmeta>
<refentrytitle>Text Widget Overview</refentrytitle>
<manvolnum>3</manvolnum>
<refmiscinfo>GTK Library</refmiscinfo>
</refmeta>
<refnamediv>
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<refname>Text Widget Overview</refname>
<refpurpose>Overview of GtkTextBuffer, GtkTextView, and friends</refpurpose>
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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</refnamediv>
<refsect1>
<title>Conceptual Overview</title>
<para>
GTK+ has an extremely powerful framework for multiline text editing. The
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primary objects involved in the process are #GtkTextBuffer, which represents the
text being edited, and #GtkTextView, a widget which can display a #GtkTextBuffer.
Each buffer can be displayed by any number of views.
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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</para>
<para>
One of the important things to remember about text in GTK+ is that it's in the
UTF-8 encoding. This means that one character can be encoded as multiple
bytes. Character counts are usually referred to as
<firstterm>offsets</firstterm>, while byte counts are called
<firstterm>indexes</firstterm>. If you confuse these two, things will work fine
with ASCII, but as soon as your buffer contains multibyte characters, bad
things will happen.
</para>
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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<para>
Text in a buffer can be marked with <firstterm>tags</firstterm>. A tag is an
attribute that can be applied to some range of text. For example, a tag might
be called "bold" and make the text inside the tag bold. However, the tag
concept is more general than that; tags don't have to affect appearance. They
can instead affect the behavior of mouse and key presses, "lock" a range of
text so the user can't edit it, or countless other things. A tag is
represented by a #GtkTextTag object. One #GtkTextTag can be applied to any
number of text ranges in any number of buffers.
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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</para>
<para>
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Each tag is stored in a #GtkTextTagTable. A tag table defines a set of
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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tags that can be used together. Each buffer has one tag table associated with
it; only tags from that tag table can be used with the buffer. A single tag
table can be shared between multiple buffers, however.
</para>
<para>
Tags can have names, which is convenient sometimes (for example, you can name
your tag that makes things bold "bold"), but they can also be anonymous (which
is convenient if you're creating tags on-the-fly).
</para>
<para>
Most text manipulation is accomplished with <firstterm>iterators</firstterm>,
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represented by a #GtkTextIter. An iterator represents a position between two
characters in the text buffer. #GtkTextIter is a struct designed to be
allocated on the stack; it's guaranteed to be copiable by value and never
contain any heap-allocated data. Iterators are not valid indefinitely;
whenever the buffer is modified in a way that affects the number of characters
in the buffer, all outstanding iterators become invalid. (Note that deleting
5 characters and then reinserting 5 still invalidates iterators, though you
end up with the same number of characters you pass through a state with a
different number).
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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</para>
<para>
Because of this, iterators can't be used to preserve positions across buffer
modifications. To preserve a position, the #GtkTextMark object is ideal. You
can think of a mark as an invisible cursor or insertion point; it floats in
the buffer, saving a position. If the text surrounding the mark is deleted,
the mark remains in the position the text once occupied; if text is inserted
at the mark, the mark ends up either to the left or to the right of the new
text, depending on its <firstterm>gravity</firstterm>. The standard text
cursor in left-to-right languages is a mark with right gravity, because it
stays to the right of inserted text.
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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</para>
<para>
Like tags, marks can be either named or anonymous. There are two marks built-in
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to #GtkTextBuffer; these are named <literal>"insert"</literal> and
<literal>"selection_bound"</literal> and refer to the insertion point and the
boundary of the selection which is not the insertion point, respectively. If
no text is selected, these two marks will be in the same position. You can
manipulate what is selected and where the cursor appears by moving these
marks around.
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
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<footnote>
<para>
If you want to place the cursor in response to a user action, be sure to use
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gtk_text_buffer_place_cursor(), which moves both at once without causing a
temporary selection (moving one then the other temporarily selects the range in
between the old and new positions).
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
</para>
</footnote>
</para>
<para>
Text buffers always contain at least one line, but may be empty (that
is, buffers can contain zero characters). The last line in the text
buffer never ends in a line separator (such as newline); the other
lines in the buffer always end in a line separator. Line separators
count as characters when computing character counts and character
offsets. Note that some Unicode line separators are represented with
multiple bytes in UTF-8, and the two-character sequence "\r\n" is also
considered a line separator.
</para>
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
</refsect1>
<refsect1>
<title>Simple Example</title>
<para>
2005-05-16 19:34:39 +00:00
The simplest usage of #GtkTextView might look like this:
<informalexample><programlisting>
GtkWidget *view;
GtkTextBuffer *buffer;
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
2005-05-16 19:34:39 +00:00
view = gtk_text_view_new (<!-- -->);
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (view));
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
gtk_text_buffer_set_text (buffer, "Hello, this is some text", -1);
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
/* Now you might put the view in a container and display it on the
* screen; when the user edits the text, signals on the buffer
* will be emitted, such as "changed", "insert_text", and so on.
*/
</programlisting></informalexample>
2005-05-16 19:34:39 +00:00
In many cases it's also convenient to first create the buffer with
gtk_text_buffer_new(), then create a widget for that buffer with
gtk_text_view_new_with_buffer(). Or you can change the buffer the widget
displays after the widget is created with gtk_text_view_set_buffer().
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
</para>
</refsect1>
<refsect1>
<title>Example of Changing Text Attributes</title>
<para>
2005-05-16 19:34:39 +00:00
There are two ways to affect text attributes in #GtkTextView.
You can change the default attributes for a given #GtkTextView, and you can
apply tags that change the attributes for a region of text. For text features
that come from the theme &mdash; such as font and foreground color &mdash; use
standard #GtkWidget functions such as gtk_widget_modify_font() or
gtk_widget_modify_text(). For other attributes there are dedicated methods on
#GtkTextView such as gtk_text_view_set_tabs().
<informalexample><programlisting>
GtkWidget *view;
GtkTextBuffer *buffer;
2002-04-20 23:57:41 +00:00
GtkTextIter start, end;
PangoFontDescription *font_desc;
GdkColor color;
GtkTextTag *tag;
2005-05-16 19:34:39 +00:00
view = gtk_text_view_new (<!-- -->);
buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (view));
gtk_text_buffer_set_text (buffer, "Hello, this is some text", -1);
/* Change default font throughout the widget */
font_desc = pango_font_description_from_string ("Serif 15");
gtk_widget_modify_font (view, font_desc);
pango_font_description_free (font_desc);
/* Change default color throughout the widget */
gdk_color_parse ("green", &amp;color);
2002-04-20 23:57:41 +00:00
gtk_widget_modify_text (view, GTK_STATE_NORMAL, &amp;color);
/* Change left margin throughout the widget */
gtk_text_view_set_left_margin (GTK_TEXT_VIEW (view), 30);
/* Use a tag to change the color for just one part of the widget */
tag = gtk_text_buffer_create_tag (buffer, "blue_foreground",
"foreground", "blue", NULL);
gtk_text_buffer_get_iter_at_offset (buffer, &amp;start, 7);
gtk_text_buffer_get_iter_at_offset (buffer, &amp;end, 12);
gtk_text_buffer_apply_tag (buffer, tag, &amp;start, &amp;end);
</programlisting></informalexample>
</para>
<para>
The <application>gtk-demo</application> application that comes with
2005-05-16 19:34:39 +00:00
GTK+ contains more example code for #GtkTextView.
</para>
</refsect1>
Re-enable the "find" dialog 2000-10-23 Havoc Pennington <hp@redhat.com> * gtk/testtext.c: Re-enable the "find" dialog * gtk/testgtk.c: Add test for gdk_drawable_get_image * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix bug where the arguments to gdk_draw_drawable were in the wrong order (gdk_window_paint_init_bg): This function was ignoring the init_region, instead of clipping to it, so the entire backing pixmap was cleared on every begin_paint() (gdk_window_begin_paint_region): Hmm, the same list-walking bug was in here again, the loop kept using the same GtkWindowPaint over and over. (gdk_window_begin_paint_region): Fix a bug where we had two x_offset instead of x_offset and y_offset * gdk/gdkdraw.c (gdk_drawable_get_image): get composite drawable before we get the image. (gdk_draw_drawable): get the composite before we draw the drawable. (gdk_drawable_real_get_composite_drawable): default get_composite_drawable implementation that returns the drawable itself * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Add get_composite_drawable virtual function * gdk/gdkwindow.c (gdk_window_begin_paint_region): Fix a cheesy list-walking bug * gdk/x11/gdkdrawable-x11.c (gdk_x11_draw_drawable): Add a hack to make this work if the source drawable is a GdkDrawableImplX11 instead of a public drawable type. This is really broken; the problem is that GdkDrawable needs a virtual method get_xid(), but of course that doesn't work in practice. Enter RTTI. Also, improve mismatched depth message. * gdk/gdkpixmap.c (gdk_pixmap_get_image): Implement get_image for GdkPixmap * gdk/x11/gdkdrawable-x11.c (gdk_drawable_impl_x11_class_init): install _gdk_x11_get_image as our implementation of get_image * gdk/x11/gdkimage-x11.c (gdk_image_get): Rename to _gdk_x11_get_image and export for use in gdkdrawable-x11.c * gdk/gdkimage.c (gdk_image_get): Make this just a wrapper around gdk_drawable_get_image * gdk/gdkdraw.c (gdk_drawable_get_image): call virtual get_image * gdk/gdkdrawable.h (struct _GdkDrawableClass ): Virtualize get_image * gtk/gtktreestore.c (gtk_tree_store_get_node): remove weird trailing semicolon after for loop
2000-10-24 00:15:14 +00:00
</refentry>