#include "login.h" #include "ui_login.h" login::login(QWidget *parent) : QMainWindow(parent), ui(new Ui::login) { ui->setupUi(this); ui->input_password->installEventFilter(this); } login::~login() { delete ui; } bool login::eventFilter(QObject *watched, QEvent *event) { if (watched==ui->input_password) //首先判断控件(这里指 lineEdit1) { if (event->type()==Qt::ClickFocus) //然后再判断控件的具体事件 (这里指获得焦点事件) { globaldata = ""; ui->input_password->setText(""); } } return QWidget::eventFilter(watched,event); // 最后将事件交给上层对话框 } void login::on_input_password_textChanged(const QString &arg1) { globaldata = ui->input_password->text(); }