@node Android Windowing
@section The Android Window System
- Android has an unusual window system; there, all windows are
+ Android's window system is unusual, in that all windows are
maximized or full-screen, and only one window can be displayed at a
-time. On larger devices, the system allows up to four windows to be
-tiled on the screen at any time.
+time. On larger devices, the system permits simultaneously tiling up
+to four windows on the screen.
- Windows on Android do not continue to exist indefinitely after they
-are created. Instead, the system may choose to close windows that are
-not on screen in order to save memory, with the assumption that the
-program will save its contents to disk and restore them later, when
-the user asks for it to be opened again. As this is obviously not
-possible with Emacs, Emacs separates the resources associated with a
-frame from its system window.
+ Windows on Android do not exist indefinitely after they are created.
+Instead, the system may choose to close windows that are not on screen
+in order to conserve memory, with the assumption that the program will
+save its contents to disk and restore them later, when the user asks
+for it to be opened again. As this is obviously not possible with
+Emacs, Emacs separates the resources associated with a frame from its
+system window.
Each system window created (including the initial window created
during Emacs startup) is appended to a list of windows that do not
modifiers (@pxref{Modifier Keys}) reported within key events, subject
to a single exception: if @key{Alt} on your keyboard is depressed,
then the @key{Meta} modifier will be reported by Emacs in its place,
-and vice versa. This irregularity is since most keyboards posses no
+and vice versa. This irregularity is since most keyboards possess no
special @key{Meta} key, and the @key{Alt} modifier is seldom employed
in Emacs.
@section Font Backends and Selection under Android
@cindex fonts, android
- Emacs supports two font backends under Android: they are respectively
-named @code{sfnt-android} and @code{android}.
+ Emacs supports two font backends under Android: they are
+respectively named @code{sfnt-android} and @code{android}.
Upon startup, Emacs enumerates all the TrueType format fonts in the
directories @file{/system/fonts} and @file{/product/fonts}, and the
``Droid Sans Mono'', and then defaults to using this font. These
fonts are then displayed by the @code{sfnt-android} font driver.
- When running on Android, Emacs currently lacks support for OpenType
-fonts. This means that only a subset of the fonts installed on the
-system are currently available to Emacs. If you are interested in
-lifting this limitation, please contact @email{emacs-devel@@gnu.org}.
+ This font driver is presently without support for OpenType fonts;
+hence, only a subset of the fonts installed on any given system are
+available to Emacs. If you are interested in lifting this limitation,
+please contact @email{emacs-devel@@gnu.org}.
If the @code{sfnt-android} font driver fails to find any fonts at
all, Emacs falls back to the @code{android} font driver. This is a
-very lousy font driver, because of limitations and inaccuracies in the
-font metrics provided by the Android platform. In that case, Emacs
-uses the ``Monospace'' typeface configured on your system; this should
-always be Droid Sans Mono.
+very poor font driver, consequent upon limitations and inaccuracies in
+the font metrics provided by the Android platform. In that case,
+Emacs uses the ``Monospace'' typeface configured on your system; this
+should always be Droid Sans Mono.
@cindex TrueType GX fonts, android
@cindex distortable fonts, android
As on X systems, Emacs supports distortable fonts under Android.
These fonts (also termed ``TrueType GX fonts'', ``variable fonts'',
and ``multiple master fonts'') provide multiple different styles
-(``Bold'', ``Italic'', etc) using a single font file.
+(``Bold'', ``Italic'', and the like) using a single font file.
When a user-installed distortable font is found, each style that a
previously discovered font provided will no longer be used. In
Since Android has no command line, there is normally no way to
specify command-line arguments when starting Emacs. This is very
nasty when you make a mistake in your Emacs initialization files that
-prevents Emacs from starting up at all, as the system normally
-prevents other programs from accessing Emacs's home directory.
+prevents Emacs from starting up at all, as the system generally
+prohibits other programs from accessing Emacs's home directory.
@xref{Initial Options}.
However, Emacs can be started with the equivalent of either the
@cindex installing extra software on Android
@cindex installing Unix software on Android
- Android includes an extremely limited set of Unix-like command line
-tools in a default installation. Several projects exist to argument
-this selection, providing options that range from improved
-reproductions of Unix command-line utilities to package repositories
-containing extensive collections of free GNU and Unix software.
+ An exceptionally limited set of Unix-like command line tools are
+distributed alongside default installations of Android. Several
+projects exist to augment this selection, providing options that range
+from improved reproductions of Unix command-line utilities to package
+repositories providing extensive collections of free GNU and Unix
+software.
@uref{http://busybox.net, Busybox} provides Unix utilities and
limited replicas of certain popular GNU programs such as
repositories containing substantial amounts of free software for Unix
systems, including compilers, debuggers, and runtimes for languages
such as C, C++, Java, Python and Common Lisp. These packages are
-normally installed from within a purpose-built terminal emulator
-application, but Emacs can access them if it is built with the same
-application signing key as the Termux terminal emulator, and with its
-``shared user ID'' set to the package name of the terminal emulator
-program. The file @file{java/INSTALL} within the Emacs distribution
-explains how to build Emacs in this fashion.
+customarily installed from within a purpose-built terminal emulator
+application, but access is also granted to Emacs when it is built with
+the same application signing key, and its ``shared user ID'' is set to
+the same package name, as that of the terminal emulator program. The
+file @file{java/INSTALL} within the Emacs distribution illustrates how
+to build Emacs in this fashion.
@uref{https://github.com/termux/termux-packages, termux-packages}
-provides the package definitions that are used by Termux to generate
-their package repositories, which may also be independently compiled
-for installation within Emacs's home directory.
+provides the package definitions used by Termux to generate their
+package repositories, which may also be independently compiled for
+installation within Emacs's home directory.
In addition to the projects mentioned above, statically linked
binaries for most Linux kernel-based systems can also be run on
projects / emacs.git / commitdiff