TdxHyperlinkClickEventArgs Class

Stores information on a hyperlink click event in a DevExpress control or its UI element.

Declaration

TdxHyperlinkClickEventArgs = class(
    TdxHyperlinkEventArgs
)

Remarks

Hyperlink click events allow you to modify hyperlink activation behavior in DevExpress controls and their UI elements.

Main API Members

The list below outlines key members of the TdxHyperlinkClickEventArgs class. These members allow you to identify the target hyperlink and its parent UI element as well as prevent a user from activating the hyperlink.

Button | Shift

Allow you to identify the clicked mouse button and the state of modifier keys at the moment of event occurrence.

Handled

Allows you to prevent hyperlink activation.

HyperlinkIndex

Returns the index of the target hyperlink in the parent UI element’s message.

Item

Provides access to the parent UI element of the target hyperlink.

Text

Returns the target hyperlink’s anchor text.

URI

Allows you to identify the hyperlink’s target URI and change it.

Code Examples

Prevent Hyperlink Activation in Layout Items

The code example in this section demonstrates OnHyperlinkClick and OnCreate event handlers. The OnHyperlinkClick event handler prevents users from activating a hyperlink that contains the MAILTO URI scheme. The OnCreate event handler associates the OnHyperlinkClick event handler with all layout items at startup.

This scenario can be useful if you define layout item captions at runtime.

Delphi

uses
  System.StrUtils;  // This unit declares the ContainsText global function
// ...

procedure TMyForm.dxLayoutControl1Item1HyperlinkClick(Sender: TObject;
  AArgs: TdxHyperlinkClickEventArgs);
begin
  if ContainsText(AArgs.URI, 'mailto') then  // If the clicked hyperlink contains the "mailto" URI scheme
    AArgs.Handled := True;  // Prevents hyperlink activation
end;

procedure TMyForm.FormCreate(Sender: TObject);  // Associates all layout items with the declared handler
var
  I: Integer;
begin
  for I := 0 to dxLayoutControl1.AbsoluteItemCount - 1 do  // Iterates through all layout items
    dxLayoutControl1.AbsoluteItems[I].OnHyperlinkClick := dxLayoutControl1Item1HyperlinkClick;
end;

C++

#include "System.StrUtils.hpp" // This header declares the ContainsText global function
// ...

void __fastcall TMyForm::dxLayoutControl1Item1HyperlinkClick(TObject* Sender,
  TdxHyperlinkClickEventArgs *AArgs)
{
  if(ContainsText(AArgs->URI, "mailto"))  // If the clicked hyperlink contains the "mailto" URI scheme
    AArgs->Handled = true;  // Prevents hyperlink activation
}

void __fastcall TMyForm::FormCreate(TObject *Sender)  // Associates all layout items with the declared handler
{
  for(int i = 0; i < dxLayoutControl1->AbsoluteItemCount; i++)  // Iterates through all layout items
    dxLayoutControl1->AbsoluteItems[i]->OnHyperlinkClick = dxLayoutControl1Item1HyperlinkClick;
}

Prevent Accidental Hyperlink Activation in Formatted Labels

The code example in this section demonstrates handlers of OnHyperlinkClick and OnShowHyperlinkHint events. The OnHyperlinkClick event handler requires a user to hold down the Ctrl key to activate a hyperlink. The OnShowHyperlinkHint event handler changes all hyperlink hints to prompt a user to hold the Ctrl key for hyperlink activation.

Delphi

procedure TMyForm.dxFormattedLabel1PropertiesHyperlinkClick(Sender: TObject;
  AArgs: TdxHyperlinkClickEventArgs);  // Requires the Ctrl key for hyperlink activation
begin
  if AArgs.Shift <> [ssCtrl] then  // If the Ctrl key is not held down
    AArgs.Handled := True;  // Prevents hyperlink activation
end;

procedure TMyForm.dxFormattedLabel1PropertiesShowHyperlinkHint(Sender: TObject;
  AArgs: TdxShowHyperlinkHintEventArgs);  // Changes all hyperlink hints
var
  AHintPrefix, AHintURI: string;
begin
  AHintPrefix := 'Ctrl-click to navigate to ';
  AHintURI := AArgs.URI.Remove(0, 8);  // Removes the URI scheme from the hyperlink hint
  AArgs.Hint := AHintPrefix + AHintURI;  // Redefines the hyperlink hint
end;

C++

void __fastcall TMyForm::dxFormattedLabel1PropertiesHyperlinkClick(TObject *Sender,
  TdxHyperlinkClickEventArgs *AArgs)  // Requires the Ctrl key for hyperlink activation
{
  if(AArgs->Shift != (TShiftState() << [ssCtrl]))  // If the Ctrl key is not held down
    AArgs->Handled = true;  // Prevents hyperlink activation
}

void __fastcall TMyForm::dxFormattedLabel1PropertiesShowHyperlinkHint(TObject *Sender,
  TdxShowHyperlinkHintEventArgs *AArgs)  // Changes all hyperlink hints
{
  UnicodeString AHintPrefix, AHintURI;
  AHintPrefix = "Ctrl-click to navigate to ";
  AHintURI = AArgs->URI.Remove(0, 8);  // Removes the URI scheme from the hyperlink hint
  AArgs->Hint = AHintPrefix + AHintURI;  // Redefines the hyperlink hint
}

Direct TdxHyperlinkClickEventArgs Class Reference

The TdxHyperlinkClickEvent procedural type references a TdxHyperlinkClickEventArgs object as the AArgs parameter.

Inheritance

TObject

TdxEventArgs

TdxHyperlinkEventArgs

TdxHyperlinkClickEventArgs