C++ UIElement::IsVisible方法代码示例

void ListView::ChangeSelection(int delta, bool additive)
{
    if (selections_.Empty())
        return;
    if (!multiselect_)
        additive = false;

    // If going downwards, use the last selection as a base. Otherwise use first
    unsigned selection = delta > 0 ? selections_.Back() : selections_.Front();
    int direction = delta > 0 ? 1 : -1;
    unsigned numItems = GetNumItems();
    unsigned newSelection = selection;
    unsigned okSelection = selection;
    PODVector<unsigned> indices = selections_;

    while (delta != 0)
    {
        newSelection += direction;
        if (newSelection >= numItems)
            break;

        UIElement* item = GetItem(newSelection);
        if (item->IsVisible())
        {
            indices.Push(okSelection = newSelection);
            delta -= direction;
        }
    }

    if (!additive)
        SetSelection(okSelection);
    else
        SetSelections(indices);
}

void UIDrag::HandleUpdate(StringHash eventType, VariantMap& eventData)
{
    auto* ui = GetSubsystem<UI>();
    UIElement* root = ui->GetRoot();

    auto* input = GetSubsystem<Input>();

    unsigned n = input->GetNumTouches();
    for (unsigned i = 0; i < n; i++)
    {
        Text* t = (Text*)root->GetChild("Touch " + String(i));
        TouchState* ts = input->GetTouch(i);
        t->SetText("Touch " + String(ts->touchID_));

        IntVector2 pos = ts->position_;
        pos.y_ -= 30;

        t->SetPosition(pos);
        t->SetVisible(true);
    }

    for (unsigned i = n; i < 10; i++)
    {
        Text* t = (Text*)root->GetChild("Touch " + String(i));
        t->SetVisible(false);
    }

    if (input->GetKeyPress(KEY_SPACE))
    {
        PODVector<UIElement*> elements;
        root->GetChildrenWithTag(elements, "SomeTag");
        for (PODVector<UIElement*>::ConstIterator i = elements.Begin(); i != elements.End(); ++i)
        {
            UIElement* element = *i;
            element->SetVisible(!element->IsVisible());
        }
    }
}

void ListView::OnKey(int key, int buttons, int qualifiers)
{
    // If no selection, can not move with keys
    unsigned numItems = GetNumItems();
    unsigned selection = GetSelection();

    // If either shift or ctrl held down, add to selection if multiselect enabled
    bool additive = multiselect_ && qualifiers & (QUAL_SHIFT | QUAL_CTRL);
    int delta = M_MAX_INT;
    int pageDirection = 1;

    if (numItems)
    {
        if (selection != M_MAX_UNSIGNED && qualifiers & QUAL_CTRL && key == KEY_C)
        {
            CopySelectedItemsToClipboard();
            return;
        }

        switch (key)
        {
        case KEY_LEFT:
        case KEY_RIGHT:
            if (selection != M_MAX_UNSIGNED && hierarchyMode_)
            {
                Expand(selection, key == KEY_RIGHT);
                return;
            }
            break;

        case KEY_RETURN:
        case KEY_RETURN2:
        case KEY_KP_ENTER:
            if (selection != M_MAX_UNSIGNED && hierarchyMode_)
            {
                ToggleExpand(selection);
                return;
            }
            break;

        case KEY_UP:
            delta = -1;
            break;

        case KEY_DOWN:
            delta = 1;
            break;

        case KEY_PAGEUP:
            pageDirection = -1;
            // Fallthru

        case KEY_PAGEDOWN:
            {
                // Convert page step to pixels and see how many items have to be skipped to reach that many pixels
                if (selection == M_MAX_UNSIGNED)
                    selection = 0;      // Assume as if first item is selected
                int stepPixels = ((int)(pageStep_ * scrollPanel_->GetHeight())) - contentElement_->GetChild(selection)->GetHeight();
                unsigned newSelection = selection;
                unsigned okSelection = selection;
                unsigned invisible = 0;
                while (newSelection < numItems)
                {
                    UIElement* item = GetItem(newSelection);
                    int height = 0;
                    if (item->IsVisible())
                    {
                        height = item->GetHeight();
                        okSelection = newSelection;
                    }
                    else
                        ++invisible;
                    if (stepPixels < height)
                        break;
                    stepPixels -= height;
                    newSelection += pageDirection;
                }
                delta = okSelection - selection - pageDirection * invisible;
            }
            break;

        case KEY_HOME:
            delta = -(int)GetNumItems();
            break;

        case KEY_END:
            delta = GetNumItems();
            break;

        default: break;
        }
    }

    if (delta != M_MAX_INT)
    {
        ChangeSelection(delta, additive);
        return;
    }

    using namespace UnhandledKey;
//.........这里部分代码省略.........