Turn to QT open the folder-CodePudding

Found a problem, don't know how to solve, ask tall person to give directions, I code like this:

Mainwindow. H

 # # ifndef MAINWINDOW_H 
# define MAINWINDOW_H 

#include  
#include  

QT_BEGIN_NAMESPACE 
The namespace Ui {class MainWindow. } 
QT_END_NAMESPACE 

The class MainWindow: public QMainWindow 
{
Q_OBJECT 

Public: 
MainWindow (QWidget * parent=nullptr); 
~ MainWindow (); 

Private: 
Ui: : MainWindow * Ui; 
QPushButton * BTN; 

Private slots: 
Void openfile (); 
}; 
# endif//MAINWINDOW_H

The main. CPP

 # include "mainwindow. H" 

#include  

Int main (int arg c, char * argv []) 
{
QApplication a(argc, argv); 
The MainWindow w; 
w.show(); 
Return a.e xec (); 
}

Mainwindow. CPP

 # include "mainwindow. H" 
# include "ui_mainwindow. H" 
#include  

MainWindow: : MainWindow (QWidget * parent) 
: QMainWindow (parent) 
, the UI (new UI: : MainWindow) 
{
The UI - & gt; SetupUi (this); 

BTN=new QPushButton; 
BTN - & gt; SetText (" open "); 
The connect (BTN, & amp; QPushButton: : clicked, this, & amp; MainWindow: : openfile); 

SetCentralWidget (BTN); 

} 

MainWindow: : ~ MainWindow () 
{
Delete the UI; 
} 

Void MainWindow: : openfile () 
{
QString fileName=QFileDialog: : getOpenFileName (this, tr (" Open File "), "/home", the tr (" Images (*. PNG *. XPM *. JPG) ")); 

}

I will put a button, and then click a file open dialog box, after the open file path, although there is no error, but when click on the button, qt output will display the following information:

 
ShellStreams: AttachShellStreams: the Initialized 
Trying to load localized resources for LANGID 2052 with Primary LANGID 4 code zh_CN name Chinese (Simplified) Resource DLL the loaded at the path C: \ Program Files \ (x86) Common Files \ \ Internet Services \ ShellStreams Apple resources \ zh_CN lproj \ ShellStreamsLocalized dllNot running under explorer. Will not set the thread locale 
11516 b1203b0 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 

11516 b1203b0 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120530 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120530 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120530 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120530 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b1203b0 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b1203b0 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b1203b0 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b1203b0 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120a10 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120a10 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120a10 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120a10 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120a10 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120a10 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120ef0 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120ef0 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120dd0 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120dd0 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120c50 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120c50 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120d70 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
11516 b120d70 ENTER: ShellStreamsFolder: : CreateViewObject 
11516 b120d10 ENTER: ShellStreamsFolder: : ShellStreamsFolder 
Pidl=1 f50e04fd020ea3a6910a2d8802b30309d140 - & gt; 2 e80853fd6f0ec379740b3d61b4a891711800 - & gt; 
nullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnull