原创 Qt::Setting the Application Icon

Setting the Application Icon

The application icon,
typically displayed in the top-left corner of an application's top-level
windows, is set by calling the QWidget::setWindowIcon() method on top-level
widgets.

In order to change the icon
of the executable application file itself, as it is presented on the desktop
(i.e., prior to application execution), it is necessary to employ another,
platform-dependent technique.

• Setting the Application
  Icon on Windows

• Setting the Application
  Icon on Mac OS X

• Setting the Application
  Icon on Common Linux Desktops
  • K Desktop Environment
    (KDE)

  • GNOME

Setting
the Application Icon on Windows

First, create an ICO format
bitmap file that contains the icon image. This can be done with e.g. Microsoft
Visual C++: Select File|New, then select the Filetab in the dialog that appears, and choose Icon. (Note that you do not need to load your application into Visual C++;
here we are only using the icon editor.)

Store the ICO file in your
application's source code directory, for example, with the name myappico.ico. Then, create a text file called, say, myapp.rc in which you put a single line of text:

Finally, assuming you are
using qmake to generate your makefiles, add this line to your myapp.pro file:

Regenerate your makefile
and your application. The .exe file will now be represented with your icon in Explorer.

If you do not use qmake, the necessary steps are: first, run the rc program on the .rc file, then link your application with the resulting .res file.

QT是跨平台的程序设计库，在windows下的程序往往想要有一个好看的图标，方法如下：

1.准备个ICO图标。例如：myappico.ico

2.用写字版新建个文件，里面就写一行：

IDI_ICON1           ICON 
 DISCARDABLE   "myappico.ico"

3.保存改名为myapp.rc并将它和图标myappico.ico一起复制到QT工程项目的目录。

4.用写字版打开你的QT工程文件（如
"myapp.pro" ），在里面最后新添一行

RC_FILE = myapp.rc

5.保存，编译工程.

Setting
the Application Icon on Mac OS X

The application icon,
typically displayed in the application dock area, is set by calling QWidget::setWindowIcon() on a top-level widget. It is
possible that the program could appear in the application dock area before the
function call, in which case a default icon will appear during the bouncing
animation.

To ensure that the correct
icon appears, both when the application is being launched, and in the Finder,
it is necessary to employ a platform-dependent technique.

Although many programs can
create icon files (.icns),
the recommended approach is to use the Icon Composer program supplied by Apple
(in theDeveloper/Application folder). Icon
Composer allows you to import several different sized icons (for use in different
contexts) as well as the masks that go with them. Save the set of icons to a
file in your project directory.

If you are using qmake to
generate your makefiles, you only need to add a single line to your .pro project file. For example, if the name of your icon file ismyapp.icns, and your project file is myapp.pro, add this line to myapp.pro:

This will ensure that qmake puts your icons in the proper place and creates an Info.plist entry
for the icon.

If you do not use qmake, you must do the following manually:

1. Create an Info.plist file for your application (using the PropertyListEditor, found in Developer/Applications).

2. Associate your .icns record with the CFBundleIconFile record in the Info.plist file (again, using the PropertyListEditor).

3. Copy the Info.plist file into your application bundle's Contents directory.

4. Copy the .icns file into your application bundle's Contents/Resources directory.

Setting
the Application Icon on Common Linux Desktops

In this section we briefly
describe the issues involved in providing icons for applications for two common
Linux desktop environments: KDE and GNOME. The core technology used to describe
application icons is the same for both desktops, and may also apply to others,
but there are details which are specific to each. The main source of
information on the standards used by these Linux desktops is freedesktop.org. For information on other Linux
desktops please refer to the documentation for the desktops you are interested
in.

Often, users do not use
executable files directly, but instead launch applications by clicking icons on
the desktop. These icons are representations of "desktop entry files"
that contain a description of the application that includes information about
its icon. Both desktop environments are able to retrieve the information in
these files, and they use it to generate shortcuts to applications on the
desktop, in the start menu, and on the panel.

More information about
desktop entry files can be found in the Desktop Entry Specification.

Although desktop entry
files can usefully encapsulate the application's details, we still need to
store the icons in the conventional location for each desktop environment. A
number of locations for icons are given in the Icon Theme Specification.

Although the path used to
locate icons depends on the desktop in use, and on its configuration, the
directory structure beneath each of these should follow the same pattern:
subdirectories are arranged by theme, icon size, and application type.
Generally, application icons are added to the hicolor theme, so a square
application icon 32 pixels in size would be stored in the hicolor/32x32/apps directory beneath the icon path.

K Desktop Environment (KDE)

Application icons can be
installed for use by all users, or on a per-user basis. A user currently logged
into their KDE desktop can discover these locations by using kde-config, for
example, by typing the following in a terminal window:

Typically, the list of
colon-separated paths printed to stdout includes the user-specific icon path
and the system-wide path. Beneath these directories, it should be possible to
locate and install icons according to the conventions described in the Icon Theme Specification.

If you are developing
exclusively for KDE, you may wish to take advantage of the KDE build system to
configure your application. This ensures that your icons are installed in the
appropriate locations for KDE.

The KDE developer website
is at http://developer.kde.org/.

GNOME

Application icons are
stored within a standard system-wide directory containing
architecture-independent files. This location can be determined by usinggnome-config, for example by
typing the following in a terminal window:

The path printed on stdout
refers to a location that should contain a directory called pixmaps; the directory structure within the pixmaps directory is described in the Icon Theme Specification.

If you are developing
exclusively for GNOME, you may wish to use the standard set of GNU Build Tools, also described in the
relevant section of theGTK+/Gnome Application
Development book. This ensures that your icons are installed in the
appropriate locations for GNOME.

The GNOME developer website
is at http://developer.gnome.org/.