Qt5 mouseless 测试

最近需要在一个嵌入式设备上使用物理按键跟Qt界面交互操作，

在这种没有鼠标的情况下，写Qt程序就要小心了，有些东东能用，

有些东东不能用，一定提前得有所考虑。

简单的交互最好只使用按钮，复杂点的，因为涉及到焦点的切换。

复杂点的，如果屏幕还要弹出输入法来，就更加麻烦一些了。

上图吧。

使用事件过滤器，将窗体所有部件的事件都集中在父窗体的事件处理函数中来处理，来决定下一个焦点切换到谁身上。

为了方便在上、下、左、右四个方向进行切换，所以使用了QGridLayout.

#ifndef ZPAGE1_H
#define ZPAGE1_H

#include <QWidget>
#include <QKeyEvent>
#include <QDebug>
#include <QGridLayout>
#include <QToolButton>
class ZPage1 : public QWidget
{
    Q_OBJECT

public:
    ZPage1(QWidget *parent = 0);
    ~ZPage1();

protected:
    bool eventFilter(QObject *obj, QEvent *event);
private slots:
    void ZSlotBtnClicked();
private:
    QGridLayout *m_gridLayout;
    QToolButton *m_btnArray[20];
};

#endif // ZPAGE1_H

#include "zpage1.h"

ZPage1::ZPage1(QWidget *parent)
    : QWidget(parent)
{
    this->setStyleSheet("QToolButton{width:50px;height:30px;}");
    this->m_gridLayout=new QGridLayout;
    qint32 tX=0;
    qint32 tY=0;
    for(qint32 i=0;i<20;i++)
    {
        this->m_btnArray[i]=new QToolButton;
        this->m_btnArray[i]->installEventFilter(this);
        this->m_btnArray[i]->setText(QString("%1").arg(i+1));
        this->m_gridLayout->addWidget(this->m_btnArray[i],tX,tY);
        if(tX++>=5)
        {
            tY++;
            tX=0;
        }
        connect(this->m_btnArray[i],SIGNAL(clicked()),this,SLOT(ZSlotBtnClicked()));
    }
    this->setLayout(this->m_gridLayout);
}

ZPage1::~ZPage1()
{
    for(qint32 i=0;i<20;i++)
    {
        delete this->m_btnArray[i];
    }
    delete this->m_gridLayout;
}
void ZPage1::ZSlotBtnClicked()
{
    QToolButton *btn=qobject_cast<QToolButton*>(sender());
    if(btn)
    {
        qDebug()<<"Button Clicked:"<<btn->text();
    }
}

bool ZPage1::eventFilter(QObject *obj, QEvent *event)
{
    if(event->type()==QEvent::KeyPress)
    {
        qint32 tCurFocusX;
        qint32 tCurFocusY;
        for(qint32 i=0;i<this->m_gridLayout->rowCount();i++)
        {
            bool bFindIt=false;
            for(qint32 j=0;j<this->m_gridLayout->columnCount();j++)
            {
                QLayoutItem *tItem=this->m_gridLayout->itemAtPosition(i,j);
                if(!tItem)
                {
                    continue;
                }
                QWidget *tFocusWidget=tItem->widget();
                if(tFocusWidget && tFocusWidget==this->focusWidget())
                {
                    qDebug()<<"oldPos:"<<i<<j;
                    tCurFocusX=i;
                    tCurFocusY=j;
                    bFindIt=true;
                    break;
                }
            }
            if(bFindIt)
            {
                break;
            }
        }

        QKeyEvent *tKeyEvent=static_cast<QKeyEvent*>(event);
        switch(tKeyEvent->key())
        {
        //"Return" is the left area Enter key,"Enter" is the right digital area Enter key.
        //they are different.
        //case Qt::Key_Enter:
        case Qt::Key_Return:
        {
            qDebug()<<"return";
            QLayoutItem *tNewItem=this->m_gridLayout->itemAtPosition(tCurFocusX,tCurFocusY);
            if(tNewItem)
            {
                QToolButton *tBtn=qobject_cast<QToolButton*>(tNewItem->widget());
                if(tBtn)
                {
                    emit tBtn->click();
                    return true;
                }
            }
        }

        case Qt::Key_Up:
            qDebug()<<"up";
            if(tCurFocusX>0)
            {
                tCurFocusX--;
            }
            break;
        case Qt::Key_Down:
            qDebug()<<"down";
            if(tCurFocusX<this->m_gridLayout->rowCount()-1)
            {
                tCurFocusX++;
            }
            break;
        case Qt::Key_Left:
            qDebug()<<"left";
            if(tCurFocusY>0)
            {
                tCurFocusY--;
            }
            break;
        case Qt::Key_Right:
            qDebug()<<"right";
            if(tCurFocusY<this->m_gridLayout->columnCount()-1)
            {
                tCurFocusY++;
            }
            break;
        default:
            break;
        }
        qDebug()<<"newPos:"<<tCurFocusX<<tCurFocusY;
        QLayoutItem *tNewItem=this->m_gridLayout->itemAtPosition(tCurFocusX,tCurFocusY);
        if(tNewItem)
        {
            tNewItem->widget()->setFocus();
        }
        //we already handle this event,so return false.
        //this cause qt do not call other event handler.
        return true;
    }
    return false;
}

慢慢看吧，亲们，不过有个小问题要注意，就是PC兼容的键盘上有2个回车键，左边常用区域叫Return，右边数字区域叫Enter，

没错，Qt5是这样编码的。

好了，剩下的工作就是开始我的嵌入式GUI规则了。包括功能实现，以及与按键互动。