Inno Setup: Install other installer and run it before continuing my install

Question

This is the [Files] portion of my code so far:

[Files]
Source: "other_installer.exe"; DestDir: "{app}"
Source: "myprogram.exe"; DestDir: "{app}"
Source: "data.dat"; DestDir: "{app}"
Source: "otherdata.dat"; DestDir: "{app}"

My program is dependent on another program to run. I've included the installer for this program ("other_installer.exe") in my installer. What I would like to do is launch this installer as soon as it has been copied, before continuing with "myprogram.exe" and the rest.

I've googled and found the documentation for BeforeInstall in the Inno Setup Help, but they don't have an example of running another application. I believe it should be something like this:

[Files]
Source: "other_installer.exe"; DestDir: "{app}"
Source: "myprogram.exe"; DestDir: "{app}"; BeforeInstall: // RUN OTHER_INSTALLER.EXE //
Source: "data.dat"; DestDir: "{app}"
Source: "otherdata.dat"; DestDir: "{app}"

Answer 1

Better for the way you go might be the AfterInstall parameter. The following script will execute the RunOtherInstaller function right after the OtherInstaller.exe file entry is processed. There it tries to execute the just installed OtherInstaller.exe file and if that fails, it reports an error message to the user. Please note that you cannot interrupt the installation from that function, so it's not much safe to do what you want this way:

[Setup]
AppName=My Program
AppVersion=1.5
DefaultDirName={pf}\My Program

[Files]
Source: "OtherInstaller.exe"; DestDir: "{app}"; AfterInstall: RunOtherInstaller
Source: "OtherFile.dll"; DestDir: "{app}"

[Code]
procedure RunOtherInstaller;
var
  ResultCode: Integer;
begin
  if not Exec(ExpandConstant('{app}\OtherInstaller.exe'), '', '', SW_SHOWNORMAL,
    ewWaitUntilTerminated, ResultCode)
  then
    MsgBox('Other installer failed to run!' + #13#10 +
      SysErrorMessage(ResultCode), mbError, MB_OK);
end;

Answer 2

Another good time to run prerequisite installers is in the PrepareToInstall event function. (See the example scripts provided with Inno for the basic structure, and TLama's code for the actual execution.)

The main advantage of PrepareToInstall is that it allows you to handle errors and reboot requests from the child installer -- using AfterInstall doesn't.

The main disadvantage of it is that you have to manually ExtractTemporaryFile anything required to run the child install, as this occurs prior to files being extracted.

Answer 3

You can use AfterInstall, look for this in the Help. When file is just copied, i'll launch the function/procedure you put as "AfterInstall:".

In this function/procedure, use Exec and launch the other installer.