Dependencies for qrc files.

rcc.props

<AdditionalDependencies Condition="'%(QtRCCCompile.AdditionalDependencies)' == ''">$(QTDIR)\bin\rcc.exe;$(MSBuildProjectFile)</AdditionalDependencies>

rcc.targets

  <Target Name="CalculateQtRCCDeps"
          DependsOnTargets="SelectQtRCCCompile"
          Outputs="%(QtRCCCompile.Identity)">
    <Message Text="Calculating dependencies for %(QtRCCCompile.Identity)" />

    <!-- Look into the qrc file and fetch all the referenced files -->
    <XmlPeek XmlInputPath="%(QtRCCCompile.FullPath)"
             Query="//file/text()">
      <Output TaskParameter="Result" ItemName="QtRCCDeps" />
    </XmlPeek>

    <!-- Add the calculated dependencies to the AdditionalDependencies -->
    <ItemGroup>
      <QtRCCCompile>
        <AdditionalDependencies>@(QtRCCDeps);%(QtRCCCompile.AdditionalDependencies)</AdditionalDependencies>
      </QtRCCCompile>
    </ItemGroup>

    <Message Text="Actual Dependencies: @(QtRCCCompile->'%(AdditionalDependencies)')" />
  </Target>

  <Target
    Name="QtRCCCompile"
    Condition="'@(QtRCCCompile)' != ''"
    DependsOnTargets="SelectQtRCCCompile;CalculateQtRCCDeps"
    Inputs="@(QtRCCCompile);%(QtRCCCompile.AdditionalDependencies);"
    Outputs="%(OutputFile)"
  >

rcc.xml

    <StringListProperty
      Name="AdditionalDependencies"
      Subtype="file"
      DisplayName="Additional Dependencies"
      Description="Provide additional dependencies that affect the end result. Note: files, listed inside the QRC are determined automatically and should not be added manually."
      IncludeInCommandLine="False"
    />