Qt代理(委托)执行的顺序

ゝ一纸荒年。 2022-09-18 04:52 105阅读 0赞

继承

QStyledItemDelegate之后重写方法： 
    class MyDelegate : public QStyledItemDelegate
    {    
    	Q_OBJECTpublic:    
    	TableWidgetDelegate(QObject *parent = 0) :QStyledItemDelegate(parent), listEditor(new ListEditor()){}    
    	~TableWidgetDelegate();    
    	QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &option, const QModelIndex &index) const;    
    	void setEditorData(QWidget *editor, const QModelIndex &index) const;    
    	void setModelData(QWidget *editor, QAbstractItemModel *model,const QModelIndex &index) const;   
    	void updateEditorGeometry(QWidget *editor,                             
    	const QStyleOptionViewItem &option, const QModelIndex &index) const;    
    	void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const;
    
    	private slots:   
    	void commitAndCloseEditor(const QModelIndex &index);    
    	void clearTriangleIcon(QWidget *editor);};
    这是新号和槽函数：
            connect(listView,SIGNAL(clicked(const QModelIndex &)),this,SLOT(commitAndCloseEditor(const QModelIndex &)));       
    		connect(this,SIGNAL(closeEditor(QWidget*)),this,SLOT(clearTriangleIcon(QWidget*)));
            void commitAndCloseEditor(const QModelIndex &index)
    		{    
    			QWidget *editor = qobject_cast<qwidget>(sender());//通过QObject::sender()来取得编辑器，它返回发射触发此槽的信号的对象。    
    			//This signal must be emitted when the editor widget has completed editing the data, and wants to write it back into the model.    
    			emit commitData(editor);   
    			//This signal is emitted when the user has finished editing an item using the specified editor.    
    			emit closeEditor(editor);}
    </qwidget>

调用顺序：

①paint

②createEditor QVariant

③updateEditorGeometry

④setEditorData

⑤paint //在④之后设置到视图上之后描画

⑥commitAndCloseEditor //发送写到model中的信号，同时发送关闭编辑器信号

⑦setModelData  //write it back into the model

//在这里面选择View上新的值进行编辑

⑧setEditorData //新的编辑值描画到视图

⑨clearTriangleIcon----------------//在closeEditor发出后做一些清除的工作

⑩paint //关闭编辑器之后再描画