如何绘制组合框的静态部分 [英] How to draw the static part of the combobox

问题描述

我有一个样式为CBS_DROPDOWNLIST和CBS_OWNERDRAWVARIABLE的自定义绘制组合框，我可以绘制下拉列表中的项目，但用户选择在组合框静态部分中绘制的项目选择项并显示选择项]，我想给它一个自定义文本，如下图所示

但是我不能确定我找到了这样的代码

    if(DrawItemStruct.CtlType == ODT_COMBOBOX)//the static part of the combo
        DrawComboText(pDC, DrawItemStruct.itemID, &DrawItemStruct.rcItem);
    else//the rest items
    {
        // Copy the text of the item to a string
        char sItem[256];
        GetString(sItem, DrawItemStruct.itemID);
        biDrawText(pDC, sItem, -1, &DrawItemStruct.rcItem, f | DT_VCENTER | DT_SINGLELINE);
    }

但是当我使用它时，我得到的所有项目都有CtlType == ODT_COMBOBOX，当我调试上面的代码时，它的静态部分返回ODT_COMBOBOX，对于下拉列表的项目返回ODT_LISTBOX.

我想知道如何解决此问题，如何检测到我在下拉列表中绘制的是静态零件还是常规项目?

解决方案

我只是检查ODS_COMBOBOXEDIT的状态.如果文档中说已为编辑控件设置了此标志，则它适用于下拉列表.

我已经检查了像您一样理智的组合框实现方式.

bool bDrawStaticControl = (pDIS->itemState & ODS_COMBOBOXEDIT)!=0;

I have a custom drawn combobox with style CBS_DROPDOWNLIST and CBS_OWNERDRAWVARIABLE I can draw the items of the dropdownlist ok but whe user select an item it is drawn in the combobox static part [the part of combo that stay visible after selecting item and show the selection], I want to give it a custom text like in the following image

But I can't determine it I found a code like this

    if(DrawItemStruct.CtlType == ODT_COMBOBOX)//the static part of the combo
        DrawComboText(pDC, DrawItemStruct.itemID, &DrawItemStruct.rcItem);
    else//the rest items
    {
        // Copy the text of the item to a string
        char sItem[256];
        GetString(sItem, DrawItemStruct.itemID);
        biDrawText(pDC, sItem, -1, &DrawItemStruct.rcItem, f | DT_VCENTER | DT_SINGLELINE);
    }

but when I used it I get all the items has CtlType == ODT_COMBOBOX, when I debugged the above code It return ODT_COMBOBOX for the static part, and for items of the drop down list it return ODT_LISTBOX.

I want to know how to fix this problem, how to detect that I'm drawing the static part or a regular item in the dropdown list?

解决方案

I just check the state for ODS_COMBOBOXEDIT. If ifthe dcumentation says that this flag is set for the edit Control, it works for the drop down list to.

I have checked combo box implementation like you that works in the sane way.

bool bDrawStaticControl = (pDIS->itemState & ODS_COMBOBOXEDIT)!=0;

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