我这个有不理解的地方帮我讲讲好吗？

Question

 #include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QTextFrame>
#include <QDebug>
#include <QLineEdit>
#include <QDialog>
#include <QPushButton>
#include <QVBoxLayout>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    QTextDocument *document=ui->textEdit->document();
    QTextFrame *rootFrame=document->rootFrame();
    QTextFrameFormat format;
    format.setBackground(Qt::blue);
    format.setBorderBrush(Qt::red);
    format.setBorder(3);
    rootFrame->setFrameFormat(format);
    QTextFrameFormat frameFormat;
    frameFormat.setBackground(Qt::lightGray);
    frameFormat.setMargin(20);
    frameFormat.setPadding(50);
    frameFormat.setBorder(6);
    frameFormat.setBorderStyle(QTextFrameFormat::BorderStyle_Dotted);
    QTextCursor cursor=ui->textEdit->textCursor();
    cursor.insertFrame(frameFormat);

    QAction *action_textFrame=new QAction(tr("框架"),this);
    connect(action_textFrame,SIGNAL(triggered()),this,SLOT(showTextFrame()));
    ui->mainToolBar->addAction(action_textFrame);

    QAction *action_textBlock=new QAction(tr("文本块"),this);
    connect(action_textBlock,SIGNAL(triggered()),this,SLOT(showTextBlock()));
    ui->mainToolBar->addAction(action_textBlock);

    QAction *action_font=new QAction(tr("字体"),this);
    action_font->setCheckable(true);
    connect(action_font,SIGNAL(toggled(bool)),this,SLOT(setTextFont(bool)));
    ui->mainToolBar->addAction(action_font);

    QAction *action_textFind=new QAction(tr("查找"),this);
    connect(action_textFind,SIGNAL(triggered()),this,SLOT(textFind()));
    ui->mainToolBar->addAction(action_textFind);
}


void MainWindow::showTextFrame()
{
    QTextDocument *document=ui->textEdit->document();
    QTextFrame *frame=document->rootFrame();
    QTextFrame::iterator it;
    for(it=frame->begin();it.atEnd()==0;++it)
    {
        QTextFrame *childFrame=it.currentFrame();
        QTextBlock childBlock=it.currentBlock();
        if(childFrame)
            qDebug()<<"frame";
        else if(childBlock.isValid())
            qDebug()<<"block:"<<childBlock.text();
    }
}


void MainWindow::showTextBlock()
{
    QTextDocument *document=ui->textEdit->document();
    QTextBlock block=document->firstBlock();
    qDebug()<<document->blockCount();
    for(int i=0;i<document->blockCount();i++)
    {
        qDebug()
        <<tr("文本块%1,文本块首行行号为:%2,长度为:%3,内容为:").arg(i).arg(block.firstLineNumber()).arg(block.length())
             <<block.text();
        block=block.next();
    }
}

void MainWindow::setTextFont(bool checked)
{
    if(checked)
    {
        QTextCursor cursor=ui->textEdit->textCursor();
        QTextBlockFormat blockFormat;
        blockFormat.setAlignment(Qt::AlignCenter);
        cursor.insertBlock(blockFormat);
        QTextCharFormat charFormat;
        charFormat.setBackground(Qt::lightGray);
        charFormat.setForeground(Qt::blue);
        charFormat.setFont(QFont(tr("宋体"),12,QFont::Bold,true));
        charFormat.setFontUnderline(true);
        cursor.setCharFormat(charFormat);
        cursor.insertText(tr("测试字体"));
    }

}

void MainWindow::textFind()
{
    QDialog *dlg=new QDialog(this);
    lineEdit=new QLineEdit(dlg);
    QPushButton *btn=new QPushButton(dlg);
    btn->setText(tr("查找下一个"));
    connect(btn,SIGNAL(clicked(bool)),this,SLOT(findNext()));
    QVBoxLayout *layout=new QVBoxLayout;
    layout->addWidget(lineEdit);
    layout->addWidget(btn);
    dlg->setLayout(layout);
    dlg->show();
}

void MainWindow::findNext()
{
    QString string=lineEdit->text();
    bool isfind=ui->textEdit->find(string,QTextDocument::FindBackward);
    if(isfind)
    {
        qDebug()<<tr("行号:%1列号:%2").arg(ui->textEdit->textCursor().blockNumber()).
                  arg(ui->textEdit->textCursor().columnNumber());
    }
}

MainWindow::~MainWindow()
{
    delete ui;
}

Answer 1

你不理解的地方，建议标志出来、并说明你的理解与问题。否则，别人给你全部注释代码，基本上是不可能的。