控件TComboBox 下拉列表中 选项长度太长 如何在选择的时候能看到完整(控件对象长度有限)
谢谢
[解决办法]
定义一int ComMaxLen;
先计算出ComboBox1中最长的ComMaxLen
(这个自己算一下,如果你的内容是固定的,也可以设ComMaxLen为一固定值,如300)
void __fastcall TForm1::ComboBox1DropDown(TObject *Sender)
{
ComboBox1->Perform(CB_SETDROPPEDWIDTH, ComMaxLen, 0);
}
[解决办法]
以前写的一个例子:
void __fastcall SetComboDropDownWidth(TComboBox *cbx, long lWidth)
{
if (lWidth < cbx->Width)
{
cbx->Canvas->Handle = GetDC(cbx->Handle);
try
{
for (int i=0; i<cbx->Items->Count; i++)
{
int nTextLen = cbx->Canvas->TextWidth(cbx->Items->Strings[i]);
if (nTextLen > lWidth)
lWidth = nTextLen;
}
lWidth += 10;
}
// Standard ComboBox drawing is Rect.Left + 2, adding the extra spacing offsets this
__finally
{
ReleaseDC(cbx->Handle, cbx->Canvas->Handle);
}
SendMessage(cbx->Handle, CB_SETDROPPEDWIDTH, lWidth, 0);
}
}
SetComboDropDownWidth(ComboBox1, 0);