OSM: small usability improvements in download dialog

git-svn-id: http://svn.osgeo.org/qgis/trunk@12517 c8812cc2-4d05-0410-92ff-de0c093fc19c

Author: wonder

python/plugins/osm/OsmDownloadDlg.py

@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 """@package OsmDownloadDlg
 Module provides simple way how to download OSM data.
 First user is asked to choose download region, output file etc.
@@ -54,7 +55,6 @@ def __init__(self, plugin):
         self.urlPathPrefix="/api/0.6/map?bbox="
 
         self.downloadButton.setDefault(True)
-        self.downloadButton.setEnabled(False)
 
         # determining default area for download
         if QgsMapLayerRegistry.instance().count()>0:
@@ -99,7 +99,6 @@ def __init__(self, plugin):
         defaultFileName=self.generateDefFileName()
         self.destdirLineEdit.setText(defaultFileName)
         self.destdirLineEdit.setEnabled(True)
-        self.downloadButton.setEnabled(True)
 
         # check default extent
         self.checkExtent()
@@ -119,12 +118,6 @@ def downloadFile(self):
         It's called after click() signal is emitted on Download button.
         """
 
-        if self.finished:
-            return
-
-        self.downloadButton.setEnabled(False)
-        self.disconnectDlgSignals()
-
         # finding out which area should be downloaded, and to where
         urlPath = self.urlPathPrefix + self.lonFromLineEdit.text() + "," + self.latFromLineEdit.text() + "," + self.lonToLineEdit.text() + "," + self.latToLineEdit.text()
         fileName = self.destdirLineEdit.text()
@@ -141,15 +134,16 @@ def downloadFile(self):
             self.outFile = None
             return
 
+        self.setEnabled(False)
+        self.finished = False
+
         # creating progress dialog for download
         self.progressDialog=QProgressDialog(self)
         # !!! don't set progress dialog modal !!! it would cause serious problems!
         self.progressDialog.setAutoClose(False)
         self.progressDialog.setWindowTitle(self.tr("OSM Download"))
         self.connect(self.progressDialog,SIGNAL("canceled()"), self.progressDlgCanceled)
 
-        self.setEnabled(False)
-        self.progressDialog.setEnabled(True)
         self.progressDialog.show()
         self.progressDialog.setLabelText(self.tr("Waiting for OpenStreetMap server ..."))
         self.progressDialog.setMaximum(1)
@@ -254,6 +248,9 @@ def httpDone(self,error):
         del self.http
         self.http=None
 
+        self.progressDialog.close()
+        self.setEnabled(True)
+
         # request was not aborted
         if error:
             self.httpSuccess=False
@@ -263,17 +260,18 @@ def httpDone(self,error):
                 del self.outFile
                 self.outFile=None
 
-            # and tell user
-            if self.errMessage==None:
-                self.errMessage="Check your internet connection"
-            QMessageBox.information(self, self.tr("OSM Download Error")
-                ,self.tr("Download failed: %1.").arg(self.errMessage))
-        else:
-            self.httpSuccess=True
+            # and tell user (if the download wasn't cancelled by user)
+            if self.errMessage != "__cancel__":
+                if self.errMessage==None:
+                    self.errMessage="Check your internet connection"
+                QMessageBox.information(self, self.tr("OSM Download Error")
+                    ,self.tr("Download failed: %1.").arg(self.errMessage))
+            return
+
+        self.httpSuccess=True
 
         # well, download process has finished successfully;
-        # close progress dialog and the whole download dialog
-        self.progressDialog.close()
+        # close the whole download dialog
         self.close()
 
 
@@ -304,15 +302,11 @@ def showChooseDirectoryDialog(self):
         Only OSM files can be selected.
         """
 
-        if self.finished:
-            return
-
         # display file open dialog and get absolute path to selected directory
         fileSelected = QFileDialog.getSaveFileName(self, "Choose file to save","download.osm", "OSM Files (*.osm)");
         # insert selected directory path into line edit control
         if not fileSelected.isNull():
             self.destdirLineEdit.setText(fileSelected)
-            self.downloadButton.setEnabled(True)
 
 
     def generateDefFileName(self):
@@ -322,9 +316,6 @@ def generateDefFileName(self):
         Default name is always unique. It consist of current timestamp and a postfix.
         """
 
-        if self.finished:
-            return
-
         prefix=QDir.tempPath() + "/"
         if self.dbm.currentKey:
             key=QString(self.dbm.currentKey)
@@ -339,9 +330,6 @@ def autoLoadClicked(self):
         """Function is called after clicking on AutoLoad checkbox.
         """
 
-        if self.finished:
-            return
-
         if not self.autoLoadCheckBox.isChecked():
             self.chkCustomRenderer.setEnabled(False)
             self.chkReplaceData.setEnabled(False)
@@ -355,9 +343,6 @@ def showExtentHelp(self):
         It shows basic information on downloading. 
         """
 
-        if self.finished:
-            return
-
         mb=QMessageBox()
         mb.setMinimumWidth(390)
         mb.information(self, self.tr("Getting data"),self.tr("The OpenStreetMap server you are downloading OSM data from (~ api.openstreetmap.org) has fixed limitations of how much data you can get. As written at <http://wiki.openstreetmap.org/wiki/Getting_Data> neither latitude nor longitude extent of downloaded region can be larger than 0.25 degrees. Note that Quantum GIS allows you to specify any extent you want, but OpenStreetMap server will reject all request that won't satisfy downloading limitations."))
@@ -370,9 +355,6 @@ def checkExtent(self):
         Result of checking is displayed on dialog.
         """
 
-        if self.finished:
-            return
-
         lim = 0.25        # download limitations of openstreetmap server in degrees
 
         # get coordinates that are currently set
@@ -406,11 +388,8 @@ def progressDlgCanceled(self):
         It aborts HTTP connection.
         """
 
-        if self.finished:
-            return
-
-        # cancel download with no message for user
-        self.cancelDownload()
+        # cancel download with a special message
+        self.cancelDownload("__cancel__")
 
 
     def setProxy(self):
@@ -420,9 +399,6 @@ def setProxy(self):
         because it's global - accessible for the whole downloader.
         """
 
-        if self.finished:
-            return
-
         # getting and setting proxy information
         settings=QSettings()
         proxyHost=QString()