nshelperappdlg.js

firefox的html解析器 本程序实现了想数据库中添加多媒体文件和文件说明

                this.mLauncher.MIMEInfo.preferredAction = this.nsIMIMEInfo.useSystemDefault;
        } else if ( this.dialogElement( "openUsing" ).selected ) {
            // For "open with", we need to check both preferred action and whether the user chose
            // a new app.
            needUpdate = this.mLauncher.MIMEInfo.preferredAction != this.nsIMIMEInfo.useHelperApp || this.appChanged();
            if ( needUpdate ) {
                this.mLauncher.MIMEInfo.preferredAction = this.nsIMIMEInfo.useHelperApp;
                // App may have changed - Update application and description
                var app = this.helperAppChoice();
                this.mLauncher.MIMEInfo.preferredApplicationHandler = app;
                this.mLauncher.MIMEInfo.applicationDescription = "";
            }
        }
        // Only care about the state of "always ask" if this dialog wasn't forced
        if ( this.mReason == REASON_CANTHANDLE )
        {
          // We will also need to update if the "always ask" flag has changed.
          needUpdate = needUpdate || this.mLauncher.MIMEInfo.alwaysAskBeforeHandling == this.dialogElement( "alwaysHandle" ).checked;

          // One last special case: If the input "always ask" flag was false, then we always
          // update.  In that case we are displaying the helper app dialog for the first
          // time for this mime type and we need to store the user's action in the mimeTypes.rdf
          // data source (whether that action has changed or not; if it didn't change, then we need
          // to store the "always ask" flag so the helper app dialog will or won't display
          // next time, per the user's selection).
          needUpdate = needUpdate || !this.mLauncher.MIMEInfo.alwaysAskBeforeHandling;

          // Make sure mime info has updated setting for the "always ask" flag.
          this.mLauncher.MIMEInfo.alwaysAskBeforeHandling = !this.dialogElement( "alwaysHandle" ).checked;
        }

        return needUpdate;
    },

    // See if the user changed things, and if so, update the
    // mimeTypes.rdf entry for this mime type.
    updateHelperAppPref: function() {
        // We update by passing this mime info into the "Edit Type" helper app
        // pref dialog.  It will update the data source and close the dialog
        // automatically.
        this.mDialog.openDialog( "chrome://communicator/content/pref/pref-applications-edit.xul",
                                 "_blank",
                                 "chrome,modal=yes,resizable=no",
                                 this );
    },

    // onOK:
    onOK: function() {
        // Verify typed app path, if necessary.
        if ( this.dialogElement( "openUsing" ).selected ) {
            var helperApp = this.helperAppChoice();
            if ( !helperApp || !helperApp.exists() ) {
                // Show alert and try again.
                var msg = this.replaceInsert( this.getString( "badApp" ), 1, this.dialogElement( "appPath" ).value );
                var svc = Components.classes[ "@mozilla.org/embedcomp/prompt-service;1" ]
                            .getService( Components.interfaces.nsIPromptService );
                svc.alert( this.mDialog, this.getString( "badApp.title" ), msg );
                // Disable the OK button.
                this.mDialog.document.documentElement.getButton( "accept" ).disabled = true;
                // Select and focus the input field if input field is not disabled
                var path = this.dialogElement( "appPath" );
                if ( !path.disabled ) {
                    path.select();
                    path.focus();
                }
                // Clear chosen application.
                this.chosenApp = null;
                // Leave dialog up.
                return false;
            }
        }

        // Remove our web progress listener (a progress dialog will be
        // taking over).
        this.mLauncher.setWebProgressListener( null );

        // saveToDisk and launchWithApplication can return errors in
        // certain circumstances (e.g. The user clicks cancel in the
        // "Save to Disk" dialog. In those cases, we don't want to
        // update the helper application preferences in the RDF file.
        try {
            var needUpdate = this.updateMIMEInfo();
            if ( this.dialogElement( "saveToDisk" ).selected )
                this.mLauncher.saveToDisk( null, false );
            else
                this.mLauncher.launchWithApplication( null, false );

            // Update user pref for this mime type (if necessary). We do not
            // store anything in the mime type preferences for the ambiguous
            // type application/octet-stream.
            if ( needUpdate &&
                 this.mLauncher.MIMEInfo.MIMEType != "application/octet-stream" )
            {
                this.updateHelperAppPref();
            }

        } catch(e) { }

        // Unhook dialog from this object.
        this.mDialog.dialog = null;

        // Close up dialog by returning true.
        return true;
    },

    // onCancel:
    onCancel: function() {
        // Remove our web progress listener.
        this.mLauncher.setWebProgressListener( null );

        // Cancel app launcher.
        try {
            const NS_BINDING_ABORTED = 0x804b0002;
            this.mLauncher.cancel(NS_BINDING_ABORTED);
        } catch( exception ) {
        }

        // Unhook dialog from this object.
        this.mDialog.dialog = null;

        // Close up dialog by returning true.
        return true;
    },

    // dialogElement:  Try cache; obtain from document if not there.
    dialogElement: function( id ) {
         // Check if we've already fetched it.
         if ( !( id in this.elements ) ) {
             // No, then get it from dialog.
             this.elements[ id ] = this.mDialog.document.getElementById( id );
         }
         return this.elements[ id ];
    },

    // chooseApp:  Open file picker and prompt user for application.
    chooseApp: function() {
        var nsIFilePicker = Components.interfaces.nsIFilePicker;
        var fp = Components.classes["@mozilla.org/filepicker;1"].createInstance( nsIFilePicker );
        fp.init( this.mDialog,
                 this.getString( "chooseAppFilePickerTitle" ),
                 nsIFilePicker.modeOpen );

        // XXX - We want to say nsIFilePicker.filterExecutable or something
        fp.appendFilters( nsIFilePicker.filterAll );

        if ( fp.show() == nsIFilePicker.returnOK && fp.file ) {
            // Remember the file they chose to run.
            this.chosenApp = fp.file;
            // Update dialog.
            this.dialogElement( "appPath" ).value = this.getPath(this.chosenApp);
        }
    },

    // dumpInfo:
    doDebug: function() {
        const nsIProgressDialog = Components.interfaces.nsIProgressDialog;
        // Open new progress dialog.
        var progress = Components.classes[ "@mozilla.org/progressdialog;1" ]
                         .createInstance( nsIProgressDialog );
        // Show it.
        progress.open( this.mDialog );
    },

    // dumpObj:
    dumpObj: function( spec ) {
         var val = "<undefined>";
         try {
             val = eval( "this."+spec ).toString();
         } catch( exception ) {
         }
         this.dump( spec + "=" + val + "\n" );
    },

    // dumpObjectProperties
    dumpObjectProperties: function( desc, obj ) {
         for( prop in obj ) {
             this.dump( desc + "." + prop + "=" );
             var val = "<undefined>";
             try {
                 val = obj[ prop ];
             } catch ( exception ) {
             }
             this.dump( val + "\n" );
         }
    },

    // getString: Fetch data string from dialog content (and cache it).
    getString: function( id ) {
        // Check if we've fetched this string already.
        if ( !( id in this.strings ) ) {
            // Try to get it.
            var elem = this.mDialog.document.getElementById( id );
            if ( elem
                 &&
                 elem.firstChild
                 &&
                 elem.firstChild.nodeValue ) {
                this.strings[ id ] = elem.firstChild.nodeValue;
            } else {
                // If unable to fetch string, use an empty string.
                this.strings[ id ] = "";
            }
        }
        return this.strings[ id ];
    },

    // replaceInsert: Replace given insert with replacement text and return the result.
    replaceInsert: function( text, insertNo, replacementText ) {
        var result = text;
        var regExp = new RegExp("#"+insertNo);
        result = result.replace( regExp, replacementText );
        return result;
    }
}

// This Component's module implementation.  All the code below is used to get this
// component registered and accessible via XPCOM.
var module = {
    firstTime: true,

    // registerSelf: Register this component.
    registerSelf: function (compMgr, fileSpec, location, type) {
        if (this.firstTime) {
            this.firstTime = false;
            throw Components.results.NS_ERROR_FACTORY_REGISTER_AGAIN;
        }
        compMgr = compMgr.QueryInterface(Components.interfaces.nsIComponentRegistrar);

        compMgr.registerFactoryLocation( this.cid,
                                         "Mozilla Helper App Launcher Dialog",
                                         this.contractId,
                                         fileSpec,
                                         location,
                                         type );
    },

    // getClassObject: Return this component's factory object.
    getClassObject: function (compMgr, cid, iid) {
        if (!cid.equals(this.cid)) {
            throw Components.results.NS_ERROR_NO_INTERFACE;
        }

        if (!iid.equals(Components.interfaces.nsIFactory)) {
            throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
        }

        return this.factory;
    },

    /* CID for this class */
    cid: Components.ID("{F68578EB-6EC2-4169-AE19-8C6243F0ABE1}"),

    /* Contract ID for this class */
    contractId: "@mozilla.org/helperapplauncherdialog;1",

    /* factory object */
    factory: {
        // createInstance: Return a new nsProgressDialog object.
        createInstance: function (outer, iid) {
            if (outer != null)
                throw Components.results.NS_ERROR_NO_AGGREGATION;

            return (new nsHelperAppDialog()).QueryInterface(iid);
        }
    },

    // canUnload: n/a (returns true)
    canUnload: function(compMgr) {
        return true;
    }
};

// NSGetModule: Return the nsIModule object.
function NSGetModule(compMgr, fileSpec) {
    return module;
}

// Since we're automatically downloading, we don't get the file picker's
// logic to check for existing files, so we need to do that here.
//
// Note - this code is identical to that in contentAreaUtils.js.
// If you are updating this code, update that code too! We can't share code
// here since this is called in a js component.
function uniqueFile(aLocalFile) {
    while (aLocalFile.exists()) {
        parts = /(-\d+)?(\.[^.]+)?$/.test(aLocalFile.leafName);
        aLocalFile.leafName = RegExp.leftContext + (RegExp.$1 - 1) + RegExp.$2;
    }
    return aLocalFile;
}