How to open the "File Browse" dialog from PyQGIS plugin code?

Question

I am in the process of developing a plugin for QGIS using Python. Note that this is my first plugin, so the query could be quite basic...

I have used this Digital Geography link to create the basic plugin, and (quite surprisingly found it easy) created the plugin files.

I am stuck at a very basic concept. Previously, while using Python IDLE, using

QtCore.QObject.connect(self.Input, QtCore.SIGNAL("clicked()"), self.OpenBrowse)

to signal a click and writing a function OpenBrowse

 def OpenBrowse(self):
 self.Input_TB.setText(filename1)

I was able to open the Windows File Browse window on click and set the File location to an adjoining text box.

How do I do this while developing the plugin in the Python file that is created by Plugin Builder.? I am very confused about where should the code be written? Because if I place the 'clicked()' actions, etc. in the Python file generated from the UI file, it is not recognizing the variables as they are not global (obviously).

I am using QGIS 2.4, on a Windows 32-bit system.

Answer 1

Let us imagine your UI file name is MyDialogFile.py. Then,

from PyQt4.QtGui import QFileDialog
from MyDialogFile import MyDialog 
def InitGui(self):
 #other stuff....
 self.dialog = MyDialog() 
def OpenBrowse(self): 
 filename1 = QFileDialog.getOpenFileName()
 self.dialog.Input_TB.setText(filename1)

• Akhil: This works in a normal IDLE program. The difference with that and PyQGIS is that the UI commands are in a different file and the actual tool execution program is in a different file. This does not work in this setup of PyQGIS. No errors, but just doesn't do what's needed..
• vinayan: @Akhil - mmm...i think you should import the UI file into the tool execution .py file..something like, from MyDialogFile import MyDialog
• vinayan: @Akhil - Updated my answer. you could look at some of the existing qgis plugins, like QuickWkt Plugin for example to see how it connects to UI, github.com/elpaso/quickwkt

Answer 2

Modifications need to be made in 3 different files in the folder generated by Plugin Builder...

QtCore.QObject.connect(self.Input, QtCore.SIGNAL("clicked()"), self.OpenBrowse)

To be added in the UI File under the main Class...

def OpenBrowse(self): 
 filename1 = QFileDialog.getOpenFileName()
 self.dialog.Input_TB.setText(filename1)

Function to be defined in the 'plugin_class_name'dialog.py file

and

self.dialog = Ui_'Class_Name'()

in the main plugin python script under the initGui() function...