提要
当多人合作开发一个项目的时，若每人创建一个工程，就会出现同一个项目中多个pro文件。pri文件就是解决多个pro文件的一种方式，方便了最后代码的合并。
示例
1.如何建立pri文件
2.pri文件与pro文件之间的联系怎样建立
如何建立pri文件
创建一个项目，在项目文件夹下创建一个文本文件，即txt文件，创建后修改其名称为xxx.pri;
.pri文件与pro文件之间的联系怎样建立
继上面创建好项目和pri文件后，用QtCreate打开项目，进入.pro文件，假如你的pro文件是这样的；
1 QT += core gui
2
3 greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
4
5 CONFIG += c++11
6
7 # The following define makes your compiler emit warnings if you use
8 # any Qt feature that has been marked deprecated (the exact warnings
9 # depend on your compiler). Please consult the documentation of the
10 # deprecated API in order to know how to port your code away from it.
11 DEFINES += QT_DEPRECATED_WARNINGS
12
13 # You can also make your code fail to compile if it uses deprecated APIs.
14 # In order to do so, uncomment the following line.
15 # You can also select to disable deprecated APIs only up to a certain version of Qt.
16 #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0
17
18 SOURCES += \
19 main.cpp \
20 largescreenlistwidget.cpp
21
22 HEADERS += \
23 dataStruct.h \
24 largescreenlistwidget.h
25
26 FORMS += \
27 largescreenlistwidget.ui
28
29 # Default rules for deployment.
30 qnx: target.path = /tmp/$${TARGET}/bin
31 else: unix:!android: target.path = /opt/$${TARGET}/bin
32 !isEmpty(target.path): INSTALLS += target
33
34 DISTFILES +=
可以看到pro文件包含了源文件，头文件，ui文件，此时将源文件，头文件，ui文件部分，剪切下来粘贴到pri文件中。
下面是pri文件的内容：
1 SOURCES += \
2 main.cpp \
3 largescreenlistwidget.cpp
4
5 HEADERS += \
6 dataStruct.h \
7 largescreenlistwidget.h
8
9 FORMS += \
10 largescreenlistwidget.ui
pri文件保存之后，进入到pro文件，将其内容改为以下：
1 QT += core gui
2
3 greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
4
5 CONFIG += c++11
6
7 # The following define makes your compiler emit warnings if you use
8 # any Qt feature that has been marked deprecated (the exact warnings
9 # depend on your compiler). Please consult the documentation of the
10 # deprecated API in order to know how to port your code away from it.
11 DEFINES += QT_DEPRECATED_WARNINGS
12
13 # You can also make your code fail to compile if it uses deprecated APIs.
14 # In order to do so, uncomment the following line.
15 # You can also select to disable deprecated APIs only up to a certain version of Qt.
16 #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0
17
18 include(largescreenlistwidget.pri)
19
20 # Default rules for deployment.
21 qnx: target.path = /tmp/$${TARGET}/bin
22 else: unix:!android: target.path = /opt/$${TARGET}/bin
23 !isEmpty(target.path): INSTALLS += target
24
25 DISTFILES +=
相比于之前的pro文件，此时的pro文件将pri文件的 内容包含了进来，实际上相当于将之前的源文件，头文件，ui文件放在了pri文件，将pri文件当作了头文件一样被包含进来。即之前包含的源文件，头文件，ui文件部分，变为了include(largescreenlistwidget.pri)。