Control Positioning and Sizing using a C++ Helper Class

// Filename: TestDefaultDlg.cpp
// 2005-08-04 nschan Initial revision.
// 2005-09-07 nschan In OnSize(), call the scroll helper OnSize() first.
//                   Adjusted positioning of some controls.

#include "stdafx.h"
#include "TestDefaultDlg.h"
#include "LayoutHelper.h"
#include "ScrollHelper.h"
#include "GroupBox.h"
#include "ImageWnd.h"
#include "resource.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

// Fixed aspect ratio for image: 4/3 = 1.333
static const int IMAGE_ASPECT_RATIO = 1333;

BEGIN_MESSAGE_MAP(CTestDefaultDlg, CDialog)
    //{{AFX_MSG_MAP(CTestDefaultDlg)
    ON_WM_MOUSEACTIVATE()
    ON_WM_PAINT()
    ON_WM_HSCROLL()
    ON_WM_VSCROLL()
    ON_WM_MOUSEWHEEL()
    ON_WM_SIZE()
    ON_BN_CLICKED(IDC_ASPECT_RATIO_CHECK, OnMaintainAspectRatioClick)
    ON_BN_CLICKED(IDC_CENTER_IMAGE_CHECK, OnCenterImageClick)
    ON_EN_CHANGE(IDC_STEP_SIZE_EDIT, OnStepSizeEditChange)
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

CTestDefaultDlg::CTestDefaultDlg(CWnd* pParent)
    : CDialog(IDD_TEST_DEFAULT_DLG, pParent)
{
    // Dialog data.
    m_maintainAspectRatio = FALSE;
    m_centerImage = FALSE;
    m_stepSize = 0;

    // Group boxes.
    m_imageDisplayBox  = new CGroupBox;
    m_layoutOptionsBox = new CGroupBox;
    m_logMessagesBox   = new CGroupBox;

    // Image wnd.
    m_imageWnd = new CImageWnd(IDB_PARK_IMAGE);

    // Create the layout helper and attach it to this dialog.
    m_layoutHelper = new CLayoutHelper;
    m_layoutHelper->SetLayoutStyle(CLayoutHelper::DEFAULT_LAYOUT);
    m_layoutHelper->AttachWnd(this);

    // Create the scroll helper and attach it to this dialog.
    m_scrollHelper = new CScrollHelper;
    m_scrollHelper->AttachWnd(this);

    // Create the dialog.
    Create(IDD_TEST_DEFAULT_DLG, pParent);
}

CTestDefaultDlg::~CTestDefaultDlg()
{
    delete m_imageDisplayBox;
    delete m_layoutOptionsBox;
    delete m_logMessagesBox;

    delete m_imageWnd;

    delete m_layoutHelper;
    delete m_scrollHelper;
}

void CTestDefaultDlg::PostNcDestroy()
{
    m_layoutHelper->DetachWnd();
    m_scrollHelper->DetachWnd();

    // Delete the C++ instance so the parent does not have
    // to worry about it.
    delete this;
}

void CTestDefaultDlg::DoDataExchange(CDataExchange* pDX)
{
    CDialog::DoDataExchange(pDX);

    //{{AFX_DATA_MAP(CTestDefaultDlg)
    DDX_Check(pDX, IDC_ASPECT_RATIO_CHECK, m_maintainAspectRatio);
    DDX_Check(pDX, IDC_CENTER_IMAGE_CHECK, m_centerImage);
    DDX_Text(pDX, IDC_STEP_SIZE_EDIT, m_stepSize);
    DDV_MinMaxInt(pDX, m_stepSize, 0, 50);
    //}}AFX_DATA_MAP
}

BOOL CTestDefaultDlg::OnInitDialog()
{
    CDialog::OnInitDialog();

    // Create the groupbox for the image wnd.
    CRect rect;
    rect.SetRect(10, 10, 344, 288);
    m_imageDisplayBox->Create(NULL, NULL, WS_CHILD | WS_VISIBLE, rect, this, IDC_IMAGE_DISPLAY_BOX, NULL);
    m_imageDisplayBox->SetText("Image Display");

    // Create the groupbox for layout options.
    rect.SetRect(350, 10, 490, 100);
    m_layoutOptionsBox->Create(NULL, NULL, WS_CHILD | WS_VISIBLE, rect, this, IDC_LAYOUT_OPTIONS_BOX, NULL);
    m_layoutOptionsBox->SetText("Layout Options");

    // Create the groupbox for log messages.
    rect.SetRect(350, 115, 490, 303);
    m_logMessagesBox->Create(NULL, NULL, WS_CHILD | WS_VISIBLE, rect, this, IDC_LOG_MESSAGES_BOX, NULL);
    m_logMessagesBox->SetText("Log Messages");

    // Create the image wnd.
    rect.SetRect(20, 20, 325, 262);
    m_imageWnd->Create(NULL, NULL, WS_CHILD | WS_VISIBLE, rect, this, IDC_IMAGE_WND, NULL);

    // Set the initial step size.
    m_layoutHelper->SetStepSize(m_stepSize);

    // Add all child controls in dialog to the layout helper.
    m_layoutHelper->AddChildControls();

    // Update constraints for image display groupbox.
    CLayoutInfo info;
    info.AddOption(CLayoutInfo::OT_MIN_LEFT,      10);
    info.AddOption(CLayoutInfo::OT_MAX_LEFT,      10);
    info.AddOption(CLayoutInfo::OT_MIN_TOP,       10);
    info.AddOption(CLayoutInfo::OT_MAX_TOP,       10);
    info.AddOption(CLayoutInfo::OT_RIGHT_OFFSET,  10);
    info.AddOption(CLayoutInfo::OT_RIGHT_ANCHOR,  360);
    info.AddOption(CLayoutInfo::OT_BOTTOM_OFFSET, 10);
    m_layoutHelper->AddControl(m_imageDisplayBox, info);

    // Update constraints for image wnd.
    info.Reset();
    info.AddOption(CLayoutInfo::OT_LEFT_OFFSET,   24);
    info.AddOption(CLayoutInfo::OT_TOP_OFFSET,    31);
    info.AddOption(CLayoutInfo::OT_RIGHT_OFFSET,  24);
    info.AddOption(CLayoutInfo::OT_RIGHT_ANCHOR,  360);
    info.AddOption(CLayoutInfo::OT_BOTTOM_OFFSET, 24);
    m_layoutHelper->AddControl(m_imageWnd, info);

    // Update constraints for layout options groupbox.
    info.Reset();
    info.AddOption(CLayoutInfo::OT_LEFT_OFFSET,   0);
    info.AddOption(CLayoutInfo::OT_LEFT_ANCHOR,   360);
    info.AddOption(CLayoutInfo::OT_TOP_OFFSET,    10);
    info.AddOption(CLayoutInfo::OT_RIGHT_OFFSET,  10);
    info.AddOption(CLayoutInfo::OT_BOTTOM_OFFSET, 10);
    info.AddOption(CLayoutInfo::OT_BOTTOM_ANCHOR, 125);
    m_layoutHelper->AddControl(m_layoutOptionsBox, info);

    // Update constraints for log messages groupbox.
    info.Reset();
    info.AddOption(CLayoutInfo::OT_LEFT_OFFSET,   0);
    info.AddOption(CLayoutInfo::OT_LEFT_ANCHOR,   360);
    info.AddOption(CLayoutInfo::OT_TOP_OFFSET,    -3);
    info.AddOption(CLayoutInfo::OT_TOP_ANCHOR,    125);
    info.AddOption(CLayoutInfo::OT_RIGHT_OFFSET,  10);
    info.AddOption(CLayoutInfo::OT_BOTTOM_OFFSET, 10);
    m_layoutHelper->AddControl(m_logMessagesBox, info);

    // Update constraints for log messages listbox.
    info.Reset();
    info.AddOption(CLayoutInfo::OT_LEFT_OFFSET,   13);
    info.AddOption(CLayoutInfo::OT_LEFT_ANCHOR,   360);
    info.AddOption(CLayoutInfo::OT_TOP_OFFSET,    19);
    info.AddOption(CLayoutInfo::OT_TOP_ANCHOR,    125);
    info.AddOption(CLayoutInfo::OT_RIGHT_OFFSET,  24);
    info.AddOption(CLayoutInfo::OT_BOTTOM_OFFSET, 24);
    m_layoutHelper->AddControl(GetDlgItem(IDC_LOG_MESSAGES_LIST), info);

    // Update constraints for step size edit box.
    info.Reset();
    info.AddOption(CLayoutInfo::OT_MIN_WIDTH,  40);
    info.AddOption(CLayoutInfo::OT_MAX_WIDTH,  40);
    info.AddOption(CLayoutInfo::OT_MIN_HEIGHT, 23);
    info.AddOption(CLayoutInfo::OT_MAX_HEIGHT, 23);
    m_layoutHelper->AddControl(GetDlgItem(IDC_STEP_SIZE_EDIT), info);

    return TRUE;  // return TRUE unless you set the focus to a control
                  // EXCEPTION: OCX Property Pages should return FALSE
}

void CTestDefaultDlg::OnOK()
{
    // Empty implementation.
}

void CTestDefaultDlg::OnCancel()
{
    // Empty implementation.
}

int CTestDefaultDlg::OnMouseActivate(CWnd* pDesktopWnd, UINT nHitTest, UINT message)
{
    int status = CDialog::OnMouseActivate(pDesktopWnd, nHitTest, message);

    // We handle this message so that when user clicks once in the
    // dialog, it will be given the focus, and this will allow
    // mousewheel messages to be directed to this window.
    SetFocus();

    return status;
}

void CTestDefaultDlg::OnPaint()
{
    CDialog::OnPaint();

    // Only purpose of handling OnPaint is to set the
    // caption text of the MDI child frame.
    CWnd* pFrame = GetParentFrame();
    if ( pFrame != NULL )
        pFrame->SetWindowText("Default Layout Style");
}

void CTestDefaultDlg::OnHScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
    m_scrollHelper->OnHScroll(nSBCode, nPos, pScrollBar);
}

void CTestDefaultDlg::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
    m_scrollHelper->OnVScroll(nSBCode, nPos, pScrollBar);
}

BOOL CTestDefaultDlg::OnMouseWheel(UINT nFlags, short zDelta, CPoint pt)
{
    BOOL wasScrolled = m_scrollHelper->OnMouseWheel(nFlags, zDelta, pt);

    return wasScrolled;
}

void CTestDefaultDlg::OnSize(UINT nType, int cx, int cy)
{
    CDialog::OnSize(nType, cx, cy);

    // Initialization: Set the reference/minimum size for layout,
    // and the display size for scrolling.
    if ( m_layoutHelper->GetReferenceSize() == CSize(0,0) )
    {
        CRect rect;
        GetClientRect(&rect);

        if ( rect.Width() > 0 && rect.Height() > 0 )
        {
            m_layoutHelper->SetReferenceSize(rect.Width(), rect.Height());
            m_layoutHelper->SetMinimumSize(rect.Width(), rect.Height());

            m_scrollHelper->SetDisplaySize(rect.Width(), rect.Height());
        }
    }

    m_scrollHelper->OnSize(nType, cx, cy);
    m_layoutHelper->OnSize(nType, cx, cy);

    UpdateLogMessages();
}

void CTestDefaultDlg::OnMaintainAspectRatioClick()
{
    UpdateData(TRUE);

    CLayoutInfo info;
    if ( m_layoutHelper->GetLayoutInfo(m_imageWnd, info) )
    {
        if ( m_maintainAspectRatio )
            info.AddOption(CLayoutInfo::OT_ASPECT_RATIO, IMAGE_ASPECT_RATIO);
        else
            info.RemoveOption(CLayoutInfo::OT_ASPECT_RATIO);

        // Update the layout info for the image wnd.
        m_layoutHelper->AddControl(m_imageWnd, info);

        // Perform the layout so the change is reflected immediately.
        m_layoutHelper->LayoutControls();
        UpdateLogMessages();
    }
}

void CTestDefaultDlg::OnCenterImageClick()
{
    UpdateData(TRUE);

    CLayoutInfo info;
    if ( m_layoutHelper->GetLayoutInfo(m_imageWnd, info) )
    {
        if ( m_centerImage )
        {
            info.AddOption(CLayoutInfo::OT_CENTER_XPOS, 180);
            info.AddOption(CLayoutInfo::OT_CENTER_YPOS, 154);
        }
        else
        {
            info.RemoveOption(CLayoutInfo::OT_CENTER_XPOS);
            info.RemoveOption(CLayoutInfo::OT_CENTER_YPOS);
        }

        // Update the layout info for the image wnd.
        m_layoutHelper->AddControl(m_imageWnd, info);

        // Perform the layout so the change is reflected immediately.
        m_layoutHelper->LayoutControls();
        UpdateLogMessages();
    }
}

void CTestDefaultDlg::OnStepSizeEditChange()
{
    UpdateData(TRUE);

    m_layoutHelper->SetStepSize(m_stepSize);

    // Perform the layout so the change is reflected immediately.
    m_layoutHelper->LayoutControls();
    UpdateLogMessages();
}

void CTestDefaultDlg::UpdateLogMessages()
{
    CListBox* pListBox = (CListBox*)GetDlgItem(IDC_LOG_MESSAGES_LIST);
    if ( pListBox == NULL || !::IsWindow(pListBox->m_hWnd) )
        return;

    pListBox->ResetContent();

    CRect rect;
    m_imageWnd->GetWindowRect(&rect);
    ScreenToClient(&rect);

    CString msg;
    msg.Format("Image position: %d, %d", rect.left, rect.top);
    pListBox->InsertString(-1, msg);
    msg.Format("Image size: %d x %d", rect.Width(), rect.Height());
    pListBox->InsertString(-1, msg);
    msg.Format("Image aspect ratio: %0.3f", 1.0 * rect.Width() / rect.Height());
    pListBox->InsertString(-1, msg);
}

// END