QDateEdit 清空

1.1 QDateEdit 清空

// 方法一:
ui->dateEdit_Vm->setSpecialValueText(" "); 

// 方法二: 自定义 QDateEdit
ui->dateEdit_vm->setNull();
class MyDateEdit : public QDateEdit   
{
    Q_OBJECT
public:
    explicit MyDateEdit(QWidget *parent = 0): QDateEdit(parent){};
    void setNull(){
        QLineEdit *edit = findChild<QLineEdit*>("qt_spinbox_lineedit");
        edit->setClearButtonEnabled(true);
        edit->clear();
        update();
    }
};

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1.2 QDateEdit 设置主动弹框

QSize sz = ui->dateEdit_Vm->geometry().size() -= QSize(3, 3);
QPoint pt(sz.width(), sz.height());
QMouseEvent evt(QEvent::MouseButtonPress, pt, Qt::LeftButton, Qt::LeftButton, Qt::NoModifier);
qApp->sendEvent(ui->dateEdit_Vm, &evt);

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1.3 QDateEdit 设置默认 23:59:59 而不是 0:00:00

设置 displayFormat 为: "yyyy-MM-dd 23:59:59"