Modify Extract Installer Example | Qt Installer Framework Manual

- Qt Installer Framework Manual
- Qt Installer Framework Examples
- Modify Extract Installer Example

# Modify Extract Installer Example

Using the extract archive hook in a component script to modify the target path.

Modify Extract Installer illustrates how to overwrite the `component.createOperationsForArchive()` function to be able to install a component to a modified path.

## Configuring the Example Installer

The installer configuration file, config.xml, in the `config` directory specifies the text and default values used in the installer:

- The `<Name>` element sets the application name and adds it to the page name and introduction text.
- The `<Version>` element sets the application version number.
- The `<Title>` element sets the installer name and displays it on the title bar.
- The `<Publisher>` element sets the publisher of the software (as shown in the Windows Control Panel, for example).
- The `<StartMenuDir>` element sets the name of the default program group for the product in the Windows Start menu.
- The `<TargetDir>` element sets the default target directory location to be within the `IfwExamples` directory in the home directory of the current user (because it uses the pre-existing variable `,` @HomeDir@, as part of the value). For more information, see Predefined Variables.

     <?xml version="1.0" encoding="UTF-8"?>
     <Installer>
         <Name>Modify Extract Installer Example</Name>
         <Version>1.0.0</Version>
         <Title>Modify Extract Installer Example</Title>
         <Publisher>Qt-Project</Publisher>
         <StartMenuDir>Qt IFW Examples</StartMenuDir>
         <TargetDir>@HomeDir@/IfwExamples/modifyextract</TargetDir>
     </Installer>

## Creating the Example Package Information File

The installer package information file, package.xml, in the `meta` directory specifies the components that are available for installation:

- The `<DisplayName>` element sets the human-readable name of the component.
- The `<Description>` element sets the human-readable description of the component.
- The `<Version>` element sets the version number of the component.
- The `<ReleaseDate>` element sets the date of release for this component version.

- The `<Default>` element is set to `true` to preselect the component in the installer.
- The `<Script>` element specifies the file name of the JavaScript file that is loaded to perform operations.

     <?xml version="1.0"?>
     <Package>
         <DisplayName>Modify extract operation</DisplayName>
         <Description>A component that uses a hook to modify the extract operation.</Description>
         <Version>1.0.1</Version>
         <ReleaseDate>2014-12-19</ReleaseDate>
         <Default>true</Default>
         <Script>installscript.js</Script>
     </Package>

## Modifying Target Path

In installscript.js, we overwrite the default `component.createOperationsForArchive()` implementation to be able to register an `Extract` operation with a custom argument:

     Component.prototype.createOperationsForArchive = function(archive)
     {
         component.addOperation("Extract", archive, "@TargetDir@/extractToAnotherPath");
     }

## Generating the Example Installer

To create the example installer, switch to the example source directory on the command line and enter the following command:

- On Windows:

       ..\..\bin\binarycreator.exe -c config\config.xml -p packages installer.exe

- On Linux or macOS:

       ../../bin/binarycreator -c config/config.xml -p packages installer

This creates the installer to the current directory.

Files:

- modifyextract/config/config.xml
- modifyextract/modifyextract.pro
- modifyextract/packages/org.qtproject.ifw.example.modifyextract/data/my_content/test.txt
- modifyextract/packages/org.qtproject.ifw.example.modifyextract/meta/installscript.js
- modifyextract/packages/org.qtproject.ifw.example.modifyextract/meta/package.xml