Creating Flash Controls for MOSS

using System;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;

using Microsoft.SharePoint;using Microsoft.SharePoint.Utilities;using Microsoft.SharePoint.WebControls;using Microsoft.SharePoint.Publishing.WebControls;using Microsoft.SharePoint.Publishing.Fields;

namespace VZ.Controls.CustomFieldControls

/// A Field control that binds to fields of type LinkField and is /// specialized to select and render embedded flash files./// The RenderFieldForDisplay function generates the HTML markup to /// display the flash file. The FlashSelector control is/// used at edit time to allow authors to select a flash file in/// the Asset Picker dialog box.{ public class FlashFieldControl : BaseFieldControl { private FlashSelector flashSelector = new FlashSelector();

        public FlashFieldControl() { }

        /// Gets and sets the value in the edit controls public override object Value { get { LinkFieldValue flashUrlValue = new LinkFieldValue(); flashUrlValue.NavigateUrl = this.flashSelector.FlashUrl; flashUrlValue.Text = LinkFieldValue.GetDefaultDisplayText(flashUrlValue.NavigateUrl);

                return flashUrlValue; } set { LinkFieldValue flashLinkFieldValue = value as LinkFieldValue; if (null != flashLinkFieldValue) { this.flashSelector.FlashUrl = flashLinkFieldValue.NavigateUrl; } else { this.flashSelector.FlashUrl = String.Empty; } } }

        /// Get the default name used to find the template and /// control for the FlashSelector in the control /// template ASCX files. protected override string DefaultTemplateName { get { return "FlashFieldControl"; } }

        private const string AllowExternalUrlsViewStateKey = "AllowExternalUrls"; /// A flag that determines whether to allow saving of external /// flash URLs. public bool AllowExternalUrls { get { // Return true by default if not already in view state. if (ViewState[AllowExternalUrlsViewStateKey] == null) { return true; } return (bool)ViewState[AllowExternalUrlsViewStateKey]; } set { ViewState[AllowExternalUrlsViewStateKey] = value; } }

        /// Creates the edit control when not in display mode. protected override void CreateChildControls() {

            base.CreateChildControls();

            if (this.ControlMode != SPControlMode.Display) { FlashSelector flashSelectorInTemplate = this.TemplateContainer.FindControl(this.TemplateName) as FlashSelector;

                if (null == flashSelectorInTemplate) { // No flash selector was found in the control // template ASCX files. Add the default selector. this.Controls.Add(this.flashSelector); } else { // Get the flash selector from the control // template ASCX file. flashSelectorInTemplate.FlashUrl = this.flashSelector.FlashUrl; this.flashSelector = flashSelectorInTemplate; } } }

        /// Gets the current value for the flash URL as stored /// in the list item. private string itemFieldValueFlashUrl { get { LinkFieldValue currentLinkValue = this.ItemFieldValue as LinkFieldValue; if (null != currentLinkValue) { return currentLinkValue.NavigateUrl; } else { return String.Empty; } } }

        /// Renders the current list item value for the flash URL /// with embedded flash player markup. /// <param name="output"></param> protected override void RenderFieldForDisplay(System.Web.UI.HtmlTextWriter output) { if (!String.IsNullOrEmpty(this.itemFieldValueFlashUrl)) { output.Write(FlashRenderingUtilities.GetFlashHtmlMarkup(this.itemFieldValueFlashUrl)); } }

        /// Verifies that the FlashUrl is valid. public override void Validate() { base.Validate(); if (this.IsValid) { LinkFieldValue currentFlashUrlValue = this.Value as LinkFieldValue;

                if (currentFlashUrlValue == null || String.IsNullOrEmpty(currentFlashUrlValue.NavigateUrl)) { // Ensure the field is not required. if (this.Field != null && this.Field.Required) { this.IsValid = false; this.ErrorMessage = "This field is required and must contain a flash file URL."; return; } else { // The field is empty and not required. // The data is valid. return; } }

                // Perform validation on the flash file URL. HtmlValidationContext validationContext = new HtmlValidationContext();

                if (!this.AllowExternalUrls) { // Restrict URLs to be either from the current site // collection or server-relative. validationContext.RestrictUrlsToSiteCollection = true; validationContext.GuidOfThisSiteCollection = SPContext.Current.Site.ID; }

                bool droppedTags; bool droppedUrls; LinkFieldValue validatedValue = validationContext.ValidateLinkValue( currentFlashUrlValue, out droppedTags, out droppedUrls);

                if (droppedUrls || String.IsNullOrEmpty(validatedValue.NavigateUrl)) { // The flash file URL in the link field value was // not valid so report the error message. // Setting IsValid to false stops saving the page. this.IsValid = false; this.ErrorMessage = "The URL for the flash file was invalid."; if (!this.AllowExternalUrls) { this.ErrorMessage += " You must select a URL within the current site collection."; } } } } }

    /// This edit control for the FlashFieldControl has /// a toolbar and text box for selecting a flash file URL. /// This example intentionally uses a separate toolbar button /// and text box for the AssetUrlSelctor to show a more complex /// example. You can use an AssetUrlSelector control instead of /// a TextBox child control, which displays its own browse button. public class FlashSelector : WebControl { private TextBox flashUrlTextBox = new TextBox();

        public FlashSelector() { }

        /// This is the flash URL value that you can edit in the text /// box or Asset Picker dialog box. public string FlashUrl { get { return this.flashUrlTextBox.Text; } set { this.flashUrlTextBox.Text = value; } }

        protected override void OnInit(EventArgs e) { base.OnInit(e);

            // This ensures that the TextBox child control receives // its postback. EnsureChildControls(); }

        /// Gets JavaScript required to launch an Asset Picker dialog /// box for choosing a flash file URL. private string GetAssetPickerButtonScript() { AssetUrlSelector flashAssetSelector = new AssetUrlSelector();

            // When the AssetUrlSelector control is not added to the // page control tree, the Page and ID properties are // required because // AssetUrlSelector.GetClientLaunchPickerReference() // needs register script in the page. flashAssetSelector.Page = this.Page; flashAssetSelector.ID = "FlashUrlAssetSelector";

            // Uses the TextBox client ID to connect the Asset Picker // dialog box to the text box. flashAssetSelector.AssetUrlClientID = this.flashUrlTextBox.ClientID;

            // Autopostback to see the new flash file rendered after // clicking OK on the Asset Picker dialog box. flashAssetSelector.AutoPostBack = true;

            flashAssetSelector.OverrideDialogTitle = "Select a flash file"; flashAssetSelector.OverrideDialogDescription = "Select a flash file to embed in this page"; flashAssetSelector.UseImageAssetPicker = false;

            return flashAssetSelector.GetClientLaunchPickerReference(); }

        private Literal flashOutput = new Literal(); protected override void CreateChildControls() { SimpleToolbar flashSelectorToolbar = new SimpleToolbar(); flashSelectorToolbar.ID = "ToolBar";

            this.Controls.Add(flashSelectorToolbar);

            Label flashUrlLabel = new Label(); flashUrlLabel.Text = "Selected flash file URL: "; flashUrlLabel.AssociatedControlID = "FlashUrlTextBox"; this.Controls.Add(flashUrlLabel);

            this.flashUrlTextBox.ID = "FlashUrlTextBox"; this.flashUrlTextBox.CssClass = "ms-input ms-lactiontable sample-flashselector-urltextbox"; this.Controls.Add(this.flashUrlTextBox);

            // Add the button after the rest so that the text box // ClientID is already determined and can be connected // in the Asset Picker dialog box client script. flashSelectorToolbar.AddToolbarButton( "SelectFlashFile", "Select a flash file", this.GetAssetPickerButtonScript(), "Open a picker to select a flash file URL");

            // Add a refresh button to perform a basic postback to // to update the FlashUrl rendering. flashSelectorToolbar.AddToolbarButton( "RefreshFlashFile", "Refresh", this.Page.ClientScript.GetPostBackEventReference(this, String.Empty), "Refresh the page to reload the current flash file URL", "/_layouts/IMAGES/refresh.gif");

            // If there is a flash file URL, this code creates // the flash player markup. this.Controls.Add(this.flashOutput); }

        protected override void OnPreRender(EventArgs e) { string flashFileOutputHtml = FlashRenderingUtilities.GetFlashHtmlMarkup(this.FlashUrl); if (String.IsNullOrEmpty(flashFileOutputHtml)) { this.flashOutput.Text = "<BR>{There is no valid flash file URL to display}<BR>"; } else { this.flashOutput.Text = "<BR>" + flashFileOutputHtml + "<BR>"; }

            base.OnPreRender(e); } }

    public static class FlashRenderingUtilities { /// Take a flash file URL and generate HTML markup /// for playing the file. /// <param name="flashUrl"></param> public static string GetFlashHtmlMarkup(string flashUrl) { // HtmlUrlAttributeEncode returns an empty string if the // URL protocol is not allowed (e.g., JavaScript:) string encodedUrl = SPHttpUtility.HtmlUrlAttributeEncode(flashUrl);

            if (String.IsNullOrEmpty(encodedUrl)) { return String.Empty; } else { return String.Format(FlashHtmlMarkupFormat, encodedUrl); } }

        // Currently, this code includes only a parameter for the flash // file URL, but it could also include parameters for the // width, height, and other rendering properties from field // control properties or authored data value properties. private const string FlashHtmlMarkupFormat = @"<object classid=""clsid:d27cdb6e-ae6d-11cf-96b8-444553540000"" codebase=""https://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,40,0"" width=""300"" height=""450""> <param name=""movie"" value=""{0}"" /> <param name=""quality"" value=""high"" /> <param name=""bgcolor"" value=""#ffffff"" /> <embed src="" mce_src=""{0}"" quality=""high"" bgcolor=""#ffffff"" width=""468"" height=""60"" name=""mymoviename"" align="" type=""application/x-shockwave-flash"" pluginspage=""https://www.macromedia.com/go/getflashplayer""> </embed> </object>"; }}