在QFileDialog中过滤 [英] Filtering in QFileDialog

问题描述

我想过滤 QFileDialog 中显示的文件，而不仅仅是文件扩展名。我在Qt文档中找到的例子只显示像 Images（* .png * .xpm * .jpg）;;文本文件（* .txt）;; XML文件（* .xml） code>等等。除此之外，我还想指定一个文件对话框，例如 not ， XML文件（* .xml）但不是备份XML文件（* .backup.xml）。

所以我遇到的问题是，我想在文件对话框中显示一些具有特定文件扩展名的文件，但是我不想显示具有特定文件名后缀的其他文件（和相同的文件扩展名）。

例如：

要显示的文件：

  file1.xml 
 file2.xml 
  

文件不显示：

  file1.backup.xml 
 file2.backup。 xml 
  

我想问一下，如果可以像这样定义一个 QFileDialog ？

解决方案

我相信你可以做的是：
$ b

1. 创建一个自定义代理模型。您可以使用 QSortFilterProxyModel 作为您的模型的基类;


2. 在代理模型中，覆盖 filterAcceptsRow 方法，并为其名称中包含。backup。字的文件返回false;
   
3. 将新的代理模型设置为文件对话框： QFileDialog :: setProxyModel ;

下面是一个例子：

代理模式：

 class FileFilterProxyModel：public QSortFilterProxyModel 
 {
 protected：
 virtual bool filterAcceptsRow（int source_row，const QModelIndex& source_parent）const; 
}; 
 
 bool FileFilterProxyModel :: filterAcceptsRow（int sourceRow，const QModelIndex& sourceParent）const 
 {
 QModelIndex index0 = sourceModel（） - > index（sourceRow，0，sourceParent） ; 
 QFileSystemModel * fileModel = qobject_cast< QFileSystemModel *>（sourceModel（））; 
 return fileModel-> fileName（index0）.indexOf（。backup。）< 0; 
 //取消注释以调用默认实现
 //返回QSortFilterProxyModel :: filterAcceptsRow（sourceRow，sourceParent）; 
 
 
 
 $ p 
 $ b 
对话框是这样创建的：
 
 
  QFileDialog对话框; 
 dialog.setProxyModel（new FileFilterProxyModel）; 
 dialog.setNameFilter（XML（* .xml））; 
 dialog.setOption（QFileDialog :: DontUseNativeDialog）; 
 dialog.exec（）; 
  
只有非本机文件对话框支持代理模式。
 
I would like to filter the files that are shown in a QFileDialog more specifically than just by file extensions. The examples I found in the Qt documentation only show filters like Images (*.png *.xpm *.jpg);;Text files (*.txt);;XML files (*.xml) and such. In addition to this I would also like to specify a filter for files that should not show up in the file dialog, e.g. XML files (*.xml) but not Backup XML files (*.backup.xml).

So the problem I have is that I would like to show some files in the file dialog that have certain file extension, but I would not like to show other files with a specific file name suffix (and the same file extension).

For example:

Files to show:  
file1.xml  
file2.xml
Files not to show:  
file1.backup.xml  
file2.backup.xml
I would like to ask if it is possible to define filters like these for a QFileDialog?
解决方案
I believe what you can do is:

Create a custom proxy model. You can use QSortFilterProxyModel as a base class for your model; 
In the proxy model override the filterAcceptsRow method and return false for files which have the ".backup." word in their names;
Set new proxy model to the file dialog: QFileDialog::setProxyModel;
Below is an example:

Proxy model:
class FileFilterProxyModel : public QSortFilterProxyModel
{
protected:
    virtual bool filterAcceptsRow(int source_row, const QModelIndex& source_parent) const;
};

bool FileFilterProxyModel::filterAcceptsRow(int sourceRow, const QModelIndex &sourceParent) const
{
    QModelIndex index0 = sourceModel()->index(sourceRow, 0, sourceParent);
    QFileSystemModel* fileModel = qobject_cast<QFileSystemModel*>(sourceModel());
    return fileModel->fileName(index0).indexOf(".backup.") < 0;
    // uncomment to call the default implementation
    //return QSortFilterProxyModel::filterAcceptsRow(sourceRow, sourceParent);
}
dialog was created this way:
QFileDialog dialog;
dialog.setProxyModel(new FileFilterProxyModel);
dialog.setNameFilter("XML (*.xml)");
dialog.setOption(QFileDialog::DontUseNativeDialog);
dialog.exec();
The proxy model is supported by non-native file dialogs only.

                        
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