Register File Extension Example

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 ** This file is part of the FOO module of the Qt Toolkit.
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 function Component()
 {
     component.loaded.connect(this, addRegisterFileCheckBox);
     installer.installationFinished.connect(this, addOpenFileCheckBoxToFinishPage);
     installer.finishButtonClicked.connect(this, openRegisteredFileIfChecked);
     component.unusualFileType = generateUnusualFileType(5)
 }

 generateUnusualFileType = function(length)
 {
     var randomString = "";
     var possible = "abcdefghijklmnopqrstuvwxyz0123456789";

     for (var i = 0; i < length; i++)
         randomString += possible.charAt(Math.floor(Math.random() * possible.length));
     return randomString;
 }

 // called as soon as the component was loaded
 addRegisterFileCheckBox = function()
 {
     // don't show when updating or uninstalling
     if (installer.isInstaller()) {
         if (installer.addWizardPageItem(component, "RegisterFileCheckBoxForm", QInstaller.TargetDirectory)) {
             component.userInterface("RegisterFileCheckBoxForm").RegisterFileCheckBox.text =
                 component.userInterface("RegisterFileCheckBoxForm").RegisterFileCheckBox.text + component.unusualFileType;
         }
     }
 }

 // here we are creating the operation chain which will be processed at the real installation part later
 Component.prototype.createOperations = function()
 {
     // call default implementation to actually install the registeredfile
     component.createOperations();

     if (component.userInterface("RegisterFileCheckBoxForm")) {
         var isRegisterFileChecked = component.userInterface("RegisterFileCheckBoxForm").RegisterFileCheckBox.checked;
     }
     if (installer.value("os") === "win") {
         var iconId = 0;
         var notepadPath = installer.environmentVariable("SystemRoot") + "\\notepad.exe";
         component.addOperation("RegisterFileType",
                                component.unusualFileType,
                                notepadPath + " '%1'",
                                "QInstaller Framework example file type",
                                "text/plain",
                                notepadPath + "," + iconId,
                                "ProgId=QtProject.QtInstallerFramework." + component.unusualFileType);
     }
     component.fileWithRegisteredType = installer.value("TargetDir") + "/registeredfile." + component.unusualFileType
     component.addOperation("Move", "@TargetDir@/registeredfile", component.fileWithRegisteredType);
 }

 openRegisteredFileIfChecked = function()
 {
     if (!component.installed)
         return;

     if (installer.value("os") == "win" && installer.isInstaller() && installer.status == QInstaller.Success) {
         var isOpenRegisteredFileChecked = component.userInterface("OpenFileCheckBoxForm").OpenRegisteredFileCheckBox.checked;
         if (isOpenRegisteredFileChecked) {
             QDesktopServices.openUrl("file:///" + component.fileWithRegisteredType);
         }
     }
 }

 addOpenFileCheckBoxToFinishPage = function()
 {
     if (installer.isInstaller() && installer.status == QInstaller.Success) {
         if (installer.addWizardPageItem(component, "OpenFileCheckBoxForm", QInstaller.InstallationFinished)) {
             component.userInterface("OpenFileCheckBoxForm").OpenRegisteredFileCheckBox.text =
                 component.userInterface("OpenFileCheckBoxForm").OpenRegisteredFileCheckBox.text + component.unusualFileType;
         }
     }
 }