我正在尝试使用 TreeView 列出目录的内容，然后通过在列表中选择文件名来选择文件名。我不想使用文件选择器对话框，因为我想限制用户访问一个目录并且不希望他们在系统中导航。我的代码工作正常，直到我想清除列表并更新它。如果我访问了一行并读取了一个列值，那么当我清除列表或使用treeselection unSelectAll() 时，我会收到错误消息：
Gtk-CRITICAL **：gtk_list_store_get_value：断言'iter_is_valid（iter，list_store）'失败
和
GLib-GObject-CRITICAL **：g_value_get_string：断言“G_VALUE_HOLDS_STRING（值）”失败
代码仍然有效，但我不喜欢这些错误。感觉就像我读错了行，但我看不出如何。请参阅我的代码：void fileForm::on_treeview_selected()在最底部。变量“f”最初是“文件名”，但我更改了它以证明即使是应该丢弃的变量也会导致 iter 出现问题。该表单是在 Glade 中构建的，并使用 GTK::Builder 进行引用。我正在使用 Linux Mint 18.2`/*
/*
* File: fileForm.h
* Author: john
*
* Created on November 16, 2017, 6:26 PM
*/
#ifndef FILEFORM_H
#define FILEFORM_H
#include <gtkmm/builder.h>
#include <gtkmm/treeview.h>
#include <gtkmm/liststore.h>
#include <gtkmm/scrolledwindow.h>
#include <gtkmm/scrollbar.h>
#include <gtkmm/cellrendererprogress.h>
#include <gtkmm/button.h>
#include <gtkmm/buttonbox.h>
#include <gtkmm/box.h>
#include <gtkmm/label.h>
#include <gtkmm/entry.h>
#include <gtkmm/window.h>
#include <gtkmm/scrolledwindow.h>
#include <sstream>
#include <dirent.h>
#include <string>
#include "generalClasses.h"
//not using Glade as can't do List Store so pointless
class fileForm : public Gtk::Window {
public:
fileForm(BaseObjectType* cobject, const Glib::RefPtr<Gtk::Builder>& refGlade);
fileForm(const fileForm& orig);
virtual ~fileForm();
void show(std::string fileExtension = "");
std::string filename = "";
protected:
Glib::RefPtr<Gtk::Builder> m_builder;
std::string m_fileExtension;
//Tree model columns:
class ModelColumns : public Gtk::TreeModel::ColumnRecord
{
public:
ModelColumns()
{ add(m_col_id); add(m_col_name); add(m_col_date);}
Gtk::TreeModelColumn<unsigned int> m_col_id;
Gtk::TreeModelColumn<Glib::ustring> m_col_name;
Gtk::TreeModelColumn<Glib::ustring> m_col_date;
};
ModelColumns m_columns;
//Child widgets:
Gtk::Button* m_topButton;
Gtk::Button* m_upButton;
Gtk::Button* m_downButton;
Gtk::Button* m_bottomButton;
Gtk::TreeView* m_treeView;
Gtk::ScrolledWindow* m_scrolledWindow;
Glib::RefPtr<Gtk::TreeSelection> m_treeSelection;
Glib::RefPtr<Gtk::ListStore> m_refTreeModel;
// Gtk::ListStore* m_refTreeModel;
Gtk::Button* m_cancelButton;
Gtk::Button* m_loadButton;
private:
//Signal handlers:
void on_loadButton_clicked();
void on_cancelButton_clicked();
void on_topButton_clicked();
void on_upButton_clicked();
void on_downButton_clicked();
void on_bottomButton_clicked();
void on_treeview_selected();
};
#endif /* FILEFORM_H */
/*
* File: fileForm.cpp
* Author: john
*
* Created on November 16, 2017, 6:26 PM
*/
#include "fileForm.h"
using namespace Glib;
using namespace std;
fileForm::fileForm(BaseObjectType* cobject, const Glib::RefPtr<Gtk::Builder>& refGlade)
: Gtk::Window(cobject),
m_builder(refGlade)
{
set_title("Select file");
m_builder->get_widget("topButton",m_topButton);
m_builder->get_widget("upButton",m_upButton);
m_builder->get_widget("downButton",m_downButton);
m_builder->get_widget("bottomButton",m_bottomButton);
m_builder->get_widget("cancelButton",m_cancelButton);
m_builder->get_widget("loadButton",m_loadButton);
m_builder->get_widget("treeview1",m_treeView);
m_builder->get_widget("scrolledwindow1", m_scrolledWindow);
m_refTreeModel = Gtk::ListStore::create(m_columns);
m_treeView->set_model(m_refTreeModel);
m_treeSelection = m_treeView->get_selection();
//Add the TreeView's view columns:
//This number will be shown with the default numeric formatting.
m_treeView->append_column("ID", m_columns.m_col_id);
m_treeView->append_column("Name", m_columns.m_col_name);
m_treeView->append_column("Date",m_columns.m_col_date);
m_cancelButton->signal_clicked().connect(sigc::mem_fun(*this, &fileForm::on_cancelButton_clicked));
m_loadButton->signal_clicked().connect(sigc::mem_fun(*this, &fileForm::on_loadButton_clicked));
m_treeSelection->signal_changed().connect(sigc::mem_fun(*this, &fileForm::on_treeview_selected),false);
}
void fileForm::show(std::string fileExtension){
//open file and list
int rowCount = 0;
char buffer[30];
DIR *d;
struct dirent *dir;
struct stat fileAttrib;
string s;
int pointPos;
filename = "";
m_treeSelection->unselect_all(); //fault occurs on this line if the row.get_value was used
m_refTreeModel->clear(); //fault occurs on this line if the row.get_value was used
d = opendir(".");
if (d)
{
while ((dir = readdir(d)) != NULL)
{
stat(dir->d_name, &fileAttrib);
s = dir->d_name;
pointPos = s.find("." + fileExtension);
s = s.substr(0,pointPos);
//Fill the TreeView's model
if ((s !=".") && (s !="..") && (s != "") && (pointPos > 0)) //show only files and no directories
{
Gtk::TreeModel::Row row = *(m_refTreeModel->append());
row[m_columns.m_col_id] = ++rowCount;
row[m_columns.m_col_name] = s;
timespecToStr(buffer, &fileAttrib.st_mtim);
if (buffer != NULL)
row[m_columns.m_col_date] = buffer;
}
}
}
if (rowCount < 12) //nasty but itll do for now
{
m_treeView->set_size_request(400,-1);
m_topButton->set_sensitive(false);
m_upButton->set_sensitive(false);
m_downButton->set_sensitive(false);
m_bottomButton->set_sensitive(false);
}
else
{
m_treeView->set_size_request(400,400);
m_topButton->set_sensitive(true);
m_upButton->set_sensitive(true);
m_downButton->set_sensitive(true);
m_bottomButton->set_sensitive(true);
}
//Make all the columns reorderable:
//This is not necessary, but it's nice to show the feature.
//You can use TreeView::set_column_drag_function() to more
//finely control column drag and drop.
/*
for(guint i = 0; i < 3; i++)
{
auto column = m_treeView->get_column(i);
column->set_reorderable();
}
*/
m_loadButton->set_sensitive(false); //disabled until a selection is made
m_cancelButton->grab_focus();
Gtk::Window::show_all();
}
void fileForm::on_loadButton_clicked()
{
//filename selected when tree selected
filename += "." + m_fileExtension;
hide();
}
void fileForm::on_cancelButton_clicked()
{
filename = "";
hide();
}
void fileForm::on_treeview_selected()
{
ustring f = "";
m_loadButton->set_sensitive(true); //disabled until a selection is made
Gtk::TreeIter treeiter = m_treeSelection->get_selected();
Gtk::TreeModel::Row row = *treeiter;
f = row.get_value(m_columns.m_col_name); //not using f this is just to test, fault still occurs
//removing the row above stops the error occuring
}