UIQ Controls - Rich Text Editor

This guide explains the UIQ control Rich Text Editor (CEikRichTextEditor). The Rich Text Editor provides functionality for the user to edit and view text with different fonts and styles together with embedded objects. The Rich Text Editor is based on the Plain Text Editor control, which is normally placed directly in a view. The Rich Text Editor can be used in a Control Stand-in control. When using the Control Stand-in control the embedded objects in the Rich Text Editor will only be represented as text in the Control Stand-in, not in their original format, for example, as bitmaps. When the Container pop-out is launched, the embedded objects are displayed in their original format.

Besides the Plain Text Editor functionality, the following functionality can be used by the application developer during the creation phase exclusively:

• Set the initial state of Rich Text Editor to Read-only, View mode or Edit mode,

• Set whether or not to prevent the cursor from wrapping upwards. When this is disabled it is possible to wrap the document from the end to the top but not vice versa. The Plain Text Editor configuration for no cursor wrapping overrides this functionality.

Besides the Plain Text Editor functionality, the following functionality can be used by the application developer at any time:

• Insert objects into the composition text,

• Change font and style of the composition text, or part of the composition text.

Control snapshot Description Rich Text Editor in editable mode. Rich Text Editor in view mode. Rich Text Editor in read only mode. Dimmed Rich Text Editor. Rich Text Editor with parser text. The parser text opens a pop-out. Rich Text Editor with icon larger than 27 pixels. Rich Text Editor with highlight on object in focus.

See the API documentation for Rich Text Editor CEikRichTextEditor.

The Rich Text Editor control is derived from Global Text Editor and Plain Text Editor, also known as Edwin. See the How To guide for Plain Text Editor.

See even the API documentation for Global Text Editor (CEikGlobalTextEditor) and Plain Text Editor (CEikEdwin).

Rich Text Editor inherits from CEikGlobalTextEditor, which inherits from CEikEdwin.

This section explains how the Rich Text Editor is constructed, used and destroyed. Source code examples are used and explained to illustrate how the Rich Text Editor control is used.

Use the following #include directive:

#include <eikrted.h>

Use the following LIBRARY directive in the project's mmp-file:

LIBRARY eikctl.lib

Resource files can be used to construct the Rich Text Editor. The resource to use is defined by the RTXTED structure, defined in Eikon.rh. The structure looks like this:

STRUCT RTXTED
    {
    WORD width=0;
    WORD height=0;
    WORD numlines=1;
    WORD textlimit=0;
    LONG flags=0;
    WORD fontcontrolflags=1;
    WORD fontnameflags=EGulNoSymbolFonts;
    LONG displayMode=1;
    }

The values given in the structure definition are default values. The structure contains the following:

• width contains the width of the editor in characters, or in pixels, depending on if the EEikEdwinWidthInPixels flag is specified,

• height shows height of the editor, in pixels,

• numlines gives the maximum number of lines which can be displayed by the editor,

• textlimit sets the maximum number of characters that can be entered into the editor where zero, the default, means no limit,

• flags shows optional bit mask of flags which control attributes of the editor, for instance whether it is read only,

• fontcontrolflags specifies font control flags,

• fontnameflags states font name flags,

• displayMode is used to set the display mode, where EDisplayModeView is default.

Flags

The Rich Text Editor can use the flags from in the Plain Text Editor. These are defined in uikon.hrh and described in the How To guide for Plain Text Editor.

In addition, resource flags, which define the behavior of the Rich Text Editor, are defined in Eikon.hrh. EDisplayModeView and EDisplayModeEdit are used when initializing a Rich Text Picture (CEikRichTextPicture).

Rich Text Editor - Resource flags EEikRTedShowAllPicturesAsIconic Shows CEikRichTextPicture objects as icons. EEikRTedTextParsers Enables text parsers for coloring of text. EEikRTedShowParserPopup Enables the parsers to show their sets of commands. EDisplayModeView Supports only navigation between parser and CEikRichTextPicture objects. EDisplayModeEdit Supports editing of text in the same manner as a common text editor.

Flags for Rich Text Editor used to set font control values are defined in gulftflg.hrh.

Gulftgflg - GulFontControl flags EGulFontControlAll All font controls EGulFontControlName Font control name EGulFontControlSize Font control size EGulFontControlBold Bold font control EGulFontControlItalic Italic font control EGulFontControlUnderline Underline font control EGulFontControlStrikethrough Strikethrough font control EGulFontControlTextColor Font text color control EGulFontControlPrintPos Print position font control

This flag is defined in gulftflg.hrh and is used to set the font name:

Gulftgflg - GulAllFonts flags EGulAllFonts All fonts.

This section discusses four different ways of constructing controls. The first three ways describe how to construct and add a control to the view of an application. The view framework is used in all three cases but in three different ways. The fourth way describes how to construct and launch a dialog from an application. The dialog framework constructs the control and adds it to the dialog.

A common way to construct controls is to specify them in the resource files and let the framework construct them from there. Specifying the controls in resource files is the preferred way of constructing controls since it allows for easier modifications compared to creating them entirely from source code.

This section covers different ways of constructing a Rich Text Editor.

3.3.1 Construction with View Framework Using Data from a Resource File

The example below describes how to construct a Rich Text Editor using the view framework.

The reason the example seems to be rather complex is because it demonstrates how to construct a complete view containing a Scrollable Container and a Layout Manager. It also encapsulates the Rich Text Editor in a Building Block. The view supports both pen and softkey styles; support of both styles in a view is optional.

1) Declare an enumeration for the controls to be used in the view in a *.hrh file. Hrh files are files to be included both in resource files (*.rss) and C++ files:

/* Declare the controls' ID in a *.hrh file for use both in resource and cpp */
enum TMyViewControls
    {
    EMyViewRichTextEditor,
    EMyViewScrollableContainer,
    EMyViewBuildingBlock,
    EMyViewNumberOfControls
    };

2) Declare the controls to be used in the view in your resource (*.rss) file:

/* Declare the set of controls to be used in the view */
RESOURCE QIK_CONTROL_COLLECTION r_my_rich_text_editor_view_controls
    {
    items =
        {
        QIK_CONTROL
            {
            unique_handle = EMyViewScrollableContainer;
            type = EQikCtScrollableContainer;
            control = r_my_rich_text_editor_scroll_pane;
            },
        QIK_CONTROL
            {
            unique_handle = EMyViewBuildingBlock;
            type = EQikCtCaptionedTwolineBuildingBlock;
            control = r_my_rich_text_editor_building_block;
            },
        QIK_CONTROL
            {
            unique_handle = EMyViewRichTextEditor;
            type = EEikCtRichTextEditor;
            control = r_my_rich_text_editor;
            }
        };
    }

3) Define the view and its contents in your resource file:

/* The view */
RESOURCE QIK_VIEW r_my_rich_text_editor_view
    {
    pages = r_my_rich_text_editor_viewpages;
    }
                
/* The view page */
RESOURCE QIK_VIEW_PAGES r_my_rich_text_editor_viewpages
    {
    pages =
        {
        QIK_VIEW_PAGE
            {
            container_unique_handle = EMyViewScrollableContainer;
            page_content = r_my_rich_text_editor_view_container_details;
            }
        };
    }

4) Define the resource for the Scrollable Container used in the view:

/* The scrollable container used in the view */
RESOURCE QIK_SCROLLABLE_CONTAINER r_my_rich_text_editor_scroll_pane
    {
    }

5) Declare the contents and properties for Scrollable Container used in the view:

/* Contents of the scrollable container used in the view */
RESOURCE QIK_SCROLLABLE_CONTAINER_SETTINGS r_my_rich_text_editor_view_container_details
    {
    controls =
        {
        QIK_CONTAINER_ITEM
            {
            unique_handle = EMyViewBuildingBlock;
            }
        };
    }

6) Define the control resource structure used in the view:

/* The rich text editor used in the view */
RESOURCE RTXTED r_my_rich_text_editor
    {
    width=200;
    height=90;
    numlines=2;
    textlimit=250;
    flags=EEikEdwinNoCursorWrap;
    }

7) Define the settings for the Building Block containing the control:

/* Settings for the EQikCtCaptionedTwolineBuildingBlock containing the rich text editor */
RESOURCE QIK_SYSTEM_BUILDING_BLOCK r_my_rich_text_editor_building_block
    {
    content =
        {
        QIK_SLOT_CONTENT
            {
            slot_id = EQikItemSlot1;
            caption = "RichTextEditor:";
            },
        QIK_SLOT_CONTENT
            {
            slot_id = EQikItemSlot2;
            unique_handle = EMyViewRichTextEditor;
            }
        };
    }

8) The configurations of the view:

RESOURCE QIK_VIEW_CONFIGURATIONS r_my_rich_text_editor_ui_configurations
    {
    configurations=
        {
        QIK_VIEW_CONFIGURATION
            {
            ui_config_mode = KQikSoftkeyStylePortrait;
            view = r_my_rich_text_editor_view;
            command_list = r_my_rich_text_editor_commands;
            },
        QIK_VIEW_CONFIGURATION
            {
            ui_config_mode = KQikPenStyleTouchPortrait;
            view = r_my_rich_text_editor_view;
            command_list = r_my_rich_text_editor_commands;
            }           
        };
    }

9) The command list for the view:

RESOURCE QIK_COMMAND_LIST r_my_rich_text_editor_commands
    {
    items =
        {
        // This command shall only be visible in debug mode because it is only
        // used to find memory leaks during development of the application.
        QIK_COMMAND
            {
            id = EEikCmdExit;
            type = EQikCommandTypeScreen;
            // Indicate that this command will only be visible in debug
            stateFlags = EQikCmdFlagDebugOnly;
            text = "Close (debug)";
            }
        };
    }

10) The view framework constructs the view described in this example with this code:

void CMySinglePageView::ViewConstructL()
    {
    ViewConstructFromResourceL(R_MY_RICH_TEXT_EDITOR_UI_CONFIGURATIONS, R_MY_RICH_TEXT_EDITOR_VIEW_CONTROLS);
    }

11) The result should look something like this:

3.3.2 Construction with Your Own C++ Code Using Data from a Resource File

The example below describes how to construct a Rich Text Editor from resource with your own C++ code.

The reason the example seems to be rather complex is because it demonstrates how to construct a complete view containing a Scrollable Container and a Layout Manager. It also encapsulates the Rich Text Editor in a Building Block.

This example uses the resource structures from the previous example. The following code creates the Rich Text Editor:

#include <eikrted.h>
#include <QikBuildingBlock.h>
#include <QikRowLayoutManager.h>
#include <QikGridLayoutManager.h>
                
void CMySinglePageView::ViewConstructL()
    {
    // Give a layout manager to the view
    CQikGridLayoutManager* gl = CQikGridLayoutManager::NewLC();
    SetLayoutManagerL(gl);
    CleanupStack::Pop(gl);
    
    // Create a container and give it to the view
    ControlProvider()->ControlInfos().AddFromResourceL(R_MY_RICH_TEXT_EDITOR_VIEW_CONTROLS);
     CQikContainerBase* container = static_cast<CQikContainerBase*>(ControlProvider()->ControlConstructIfNeededL(EMyViewScrollableContainer, *this));
    ASSERT(container);
    Controls().AppendLC(container);
    CleanupStack::Pop(container);
    
    // Create a layout manager to be used inside the container
    CQikRowLayoutManager* rowlayout = CQikRowLayoutManager::NewLC();
    container->SetLayoutManagerL(rowlayout);
    CleanupStack::Pop(rowlayout);
    
    // Create the building block (containing a Rich Text Editor) and add it to the container
    CQikBuildingBlock* block = CQikBuildingBlock::CreateSystemBuildingBlockL(EQikCtCaptionedTwolineBuildingBlock);
    container->AddControlLC(block, EMyViewBuildingBlock);
    TResourceReader blockReader;
    iCoeEnv->CreateResourceReaderLC(blockReader,R_MY_RICH_TEXT_EDITOR_BUILDING_BLOCK);
    block->ConstructFromResourceL(blockReader, *ControlProvider());
    CleanupStack::PopAndDestroy(); //blockReader
    CleanupStack::Pop(block);           
    }

What the code does

1) Initializes the Command Manager with an empty Command List. The controls placed in the view add their commands to the Command List when they receive focus.

2) Creates a Layout Manager for the view. The Grid Layout Manager fills the view with its only control in this example, the Scrollable Container.

3) Loads the control collection R_MY_VIEW_CONTROLS into the Control Provider. Then the Control Provider is asked to create the Scrollable Container.

4) Uses the MopGetObjectNoChaining function to determine whether the control that was created really is a class of the type CQikContainerBase before it is added to the view.

5) Creates a Layout Manager to control the layout inside the container. Adds the Layout Manager to the container.

6) Constructs the Building Block containing the Rich Text Editor from the resource R_MY_BUILDING_BLOCK. Adds the Building Block to the container.

The Rich Text Editor can also be created without a Building Block. In that case, replace the last section in the code above, from the "Create building block..." comment, with the following code.

Since a pointer to the control is declared here, eikrted.h needs to be included in the cpp-file and eikctl.lib in the mmp-file.

// Create the Rich Text Editor and add it to the container
TResourceReader reader;
iEikonEnv->CreateResourceReaderLC(reader, R_MY_RICH_TEXT_EDITOR);
CEikRichTextEditor* rted = new (ELeave) CEikRichTextEditor();
container->AddControlLC(rted, EMyViewRichTextEditor);
rted->ConstructFromResourceL(reader);
rted->SetUniqueHandle(EMyViewRichTextEditor);
CleanupStack::Pop(rted);
CleanupStack::PopAndDestroy(); //reader

Use AddControlLC to add controls to a Scrollable Container. Add the controls as soon as they are created. Do not push them onto the Cleanup Stack before they are added. Do not pop them from the Cleanup Stack until they are fully constructed. A TCleanupItem created in AddControlLC will make sure that the control is both cleaned up and removed from the Components Array if a leave occurs before the control is fully constructed.

3.3.3 Construction Solely from C++ Code

The example below describes how to construct a Rich Text Editor solely from C++ code.

The reason the example seems to be rather complex is because it demonstrates how to construct a complete view containing a Scrollable Container and a Layout Manager.

The following source code constructs a Rich Text Editor:

#include <QikScrollableContainer.h>
#include <QikRowLayoutManager.h>
#include <QikGridLayoutManager.h>
#include <QikBuildingBlock.h>
#include <eikrted.h>      

void CMySinglePageView::ViewConstructL()
    {                   
    CQikGridLayoutManager* gridlayout = CQikGridLayoutManager::NewLC();
    SetLayoutManagerL(gridlayout);
    CleanupStack::Pop(gridlayout);
    
    // Create a container and add it to the view
    CQikScrollableContainer* container = new (ELeave) CQikScrollableContainer();
    Controls().AppendLC(container);
    container->ConstructL(EFalse);
    CleanupStack::Pop(container);
    
    // Create a layout manager to be used inside the container
    CQikRowLayoutManager* rowlayout = CQikRowLayoutManager::NewLC();
    container->SetLayoutManagerL(rowlayout);
    CleanupStack::Pop(rowlayout);
    
    // Create the Rich Text Editor and add it to the container
    CEikRichTextEditor* rted = new (ELeave) CEikRichTextEditor();
    container->AddControlLC(rted, EMyViewRichTextEditor);
    rted->ConstructL(2,250,CEikRichTextEditor::ENoCursorWrap,1,0, CEikRichTextEditor::EDisplayModeView);
    rted->SetObserver(this);
    rted->SetUniqueHandle(EMyViewRichTextEditor);
    CleanupStack::Pop(rted);
    }

What the code does

1) Initializes The Command Manager with an empty Command List. The controls placed in the view add their commands to the Command List when they receive focus.

2) Creates a Layout Manager for the view. The Grid Layout Manager fills the view with its only control in this example, the Scrollable Container.

3) Instantiates a container and adds it to the view.

4) Creates a Layout Manager and adds it to the container.

5) Creates the Rich Text Editor control from C++ code. Sets the view, this, to be an observer of the Rich Text Editor. The view's base class, CQikViewBase, handles focus changes in its method HandleControlEventL. For more details see the section below on how to be notified with Control Events.

3.3.4 Construction with the Dialog Framework Using Data from a Resource File

The Rich Text Editor can be constructed from resource files in dialogs as well. To construct a dialog from resource a valid resource definition of that dialog must be in one of the project's resource files.

An example of a dialog resource containing the control is given below. For more information about the dialog class and its resource structure see CEikDialog and DIALOG in the API documentation.

1) Declare a dialog resource containing the Rich Text Editor control:

RESOURCE DIALOG r_my_rich_text_editor_dialog
    {
    title = "Rich Text Editor Test";
    flags = EEikDialogFlagWait;
    items =
        {
        DLG_LINE
            {
            prompt = "Rich Text Editor:";
            type = EEikCtRichTextEditor;
            control = RTXTED
                {
                width = 10;
                numlines = 2;
                textlimit = 250;
                flags = EEikEdwinResizable;
                };
            }
        };
    }

The resource properties inside the Control Block are the same as the ones described in the previous section.

2) Launch the dialog using the following source code. The dialog resource ID is passed as an argument:

CEikDialog* dlg = new (ELeave) CEikDialog();
dlg->ExecuteLD(R_MY_RICH_TEXT_EDITOR_DIALOG);

The function returns immediately if EEikDialogFlagWait has not been specified in the dialog resource. If EEikDialogFlagWait is specified it returns when the dialog exits. The dialog framework will in both situations delete the dialog appropriately as indicated by the D suffix of the ExcecuteLD function name.

This section covers the most common functions used for interacting with the control.

When constructing the control with resource data, no reference to the control is available in the view class. When constructing the control with code, the preferred way might be to not save a reference to the control. In both these cases, the LocateControlByUniqueHandle function is used to get a pointer to the control by supplying the control's unique handle. When constructing the view and the control from code, you must explicitly set this unique handle by calling the method SetUniqueHandle. See the code examples below.

Note that the function will return NULL if the control could not be found. Always check the pointer before using it!

// Set the unique handle
rted->SetUniqueHandle(EMyViewRichTextEditor);

// Get a pointer to the Rich Text Editor control
CEikRichTextEditor* rted = LocateControlByUniqueHandle<CEikRichTextEditor>(EMyViewRichTextEditor)

3.4.1 How to Get the Text of the Control

Get the text of the control by using the following code:

HBufC* text = rted->GetTextInHBufL();

3.4.2 How to Set the Text of the Control

Set the text of the control by using the following code:

_LIT(KText, "Testing the Rich Text Editor. Testing the Rich Text Editor");
rted->SetTextL(&KText);

3.4.3 How to be Notified with Control Events

In order to be notified when the Rich Text Editor changes state you must add an observer to the Rich Text Editor. An observer is an object of the type MCoeControlObserver. The observer receives a function call to its function HandleControlEventL(CCoeControl* aControl, TCoeEvent aEventType) when the Rich Text Editor changes state.

The view base class, CQikViewBase, implements the MCoeControlObserver. The HandleControlEventL function must be overloaded in the view class, because the view inherits from CQikViewBase.

The following source code example shows how to add an object as an observer and how to receive events from the Rich Text Editor:

void CMySinglePageView::ViewConstructL()
    {
    // Construction code
    …
    // Adding this object as an observer
    rted->SetObserver(this);
    }
                            
void CMySinglePageView::HandleControlEventL(CCoeControl* aControl, TCoeEvent aEventType)
    {
    // Call base class to get focus navigation right
    CQikViewBase::HandleControlEventL(aControl, aEventType);

    CEikRichTextEditor* rted = LocateControlByUniqueHandle<CEikRichTextEditor>(EMyViewRichTextEditor);

    if (aControl == rted)
        {
        switch(aEventType)
            {
            case EEventStateChanged:
                // The internal state of the Rich Text Editor was changed,
                // for example, due to another item being selected. 
                break;          
                                        
            case EEventRequestExit:
                break;
                                        
            case EEventRequestCancel:
                break;
                                        
            case EEventRequestFocus:
                // The Rich Text Editor received a pointer down event
                break;
                                        
            case EEventPrepareFocusTransition:
                // A focus change is about to appear
                break;
                                    
            case EEventInteractionRefused:
                // The Rich Text Editor is dimmed and received a
                // pointer down event.
                break;
                                    
            default:
                break;
            }
        }
    }

The reason for calling the base class's HandleControlEventL function is that the view base class, CQikViewBase, handles focus management between controls in the view. If the control's observer is not a class which derives from CQikViewBase, focus management must be resolved by the observer itself. If a control requests focus and does not get it from the observer, it will generate a panic in some cases if the observer does not leave.

For more details on the TCoeEvent type, see class MCoeControlObserver in the API documentation.

Destroying the control is just a matter of invoking operator delete on the Rich Text Editor object.

Subclassing Rich Text Editor is not recommended.