《QT实用小工具·四十四》支持图片和动图的文本编辑器

本文主要是介绍《QT实用小工具·四十四》支持图片和动图的文本编辑器，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

1、概述
源码放在文章末尾

该项目实现了一个功能丰富的文本编辑器，除了包含文本常规的编辑功能，还包括图片的插入功能和动图的插入功能，项目demo演示如下所示：
在这里插入图片描述

项目部分代码如下所示：

#include "imagehelper.h"#include <QFile>
#include <QFileInfo>
#include <QQmlFile>
#include <QQuickTextDocument>
#include <QDebug>Api::Api(QObject *parent): QObject(parent)
{
}bool Api::exists(const QString &arg)
{return QFile::exists(arg);
}QString Api::baseName(const QString &arg)
{return QFileInfo(arg).baseName();
}ImageHelper::ImageHelper(QObject *parent): QObject(parent),m_maxWidth(120),m_maxHeight(120)
{}ImageHelper::~ImageHelper()
{cleanup();
}void ImageHelper::insertImage(const QUrl &url)
{QImage image = QImage(QQmlFile::urlToLocalFileOrQrc(url));if (image.isNull()){qDebug() << "不支持的图像格式";return;}QString filename = url.toString();QString suffix = QFileInfo(filename).suffix();if (suffix == "GIF" || suffix == "gif") //如果是gif，则单独处理{QString gif = filename;if (gif.left(4) == "file")gif = gif.mid(8);else if (gif.left(3) == "qrc")gif = gif.mid(3);textCursor().insertHtml("<img src='" + url.toString() + "' width = " +QString::number(qMin(m_maxWidth, image.width())) + " height = " +QString::number(qMin(m_maxHeight, image.height()))+ "/>");textDocument()->addResource(QTextDocument::ImageResource, url, image);if (m_urls.contains(url))return;else{QMovie *movie = new QMovie(gif);movie->setCacheMode(QMovie::CacheNone);connect(movie, &QMovie::finished, movie, &QMovie::start);   //循环播放connect(movie, &QMovie::frameChanged, this, [url, this](int){QMovie *movie = qobject_cast<QMovie *>(sender());textDocument()->addResource(QTextDocument::ImageResource, url, movie->currentPixmap());emit needUpdate();});m_urls[url] = movie;movie->start();}}else{        QTextImageFormat format;format.setName(filename);format.setWidth(qMin(m_maxWidth, image.width()));format.setHeight(qMin(m_maxHeight, image.height()));textCursor().insertImage(format, QTextFrameFormat::InFlow);}
}void ImageHelper::cleanup()
{for (auto it : m_urls)it->deleteLater();m_urls.clear();
}QQuickTextDocument* ImageHelper::document() const
{return  m_document;
}void ImageHelper::setDocument(QQuickTextDocument *document)
{if (document != m_document){m_document = document;emit documentChanged();}
}int ImageHelper::cursorPosition() const
{return m_cursorPosition;
}void ImageHelper::setCursorPosition(int position)
{if (position != m_cursorPosition){m_cursorPosition = position;emit cursorPositionChanged();}
}int ImageHelper::selectionStart() const
{return m_selectionStart;
}void ImageHelper::setSelectionStart(int position)
{if (position != m_selectionStart){m_selectionStart = position;emit selectionStartChanged();}
}int ImageHelper::selectionEnd() const
{return m_selectionEnd;
}void ImageHelper::setSelectionEnd(int position)
{if (position != m_selectionEnd){m_selectionEnd = position;emit selectionEndChanged();}
}int ImageHelper::maxWidth() const
{return m_maxWidth;
}void ImageHelper::setMaxWidth(int max)
{if (max != m_maxWidth){m_maxWidth = max;emit maxWidthChanged();}
}int ImageHelper::maxHeight() const
{return m_maxHeight;
}void ImageHelper::setMaxHeight(int max)
{if (max != m_maxHeight){m_maxHeight = max;emit maxHeightChanged();}
}QTextDocument* ImageHelper::textDocument() const
{if (m_document)return m_document->textDocument();else return nullptr;
}QTextCursor ImageHelper::textCursor() const
{QTextDocument *doc = textDocument();if (!doc)return QTextCursor();QTextCursor cursor = QTextCursor(doc);if (m_selectionStart != m_selectionEnd){cursor.setPosition(m_selectionStart);cursor.setPosition(m_selectionEnd, QTextCursor::KeepAnchor);}else{cursor.setPosition(m_cursorPosition);}return cursor;
}