mirror of
https://github.com/qgis/QGIS.git
synced 2025-02-24 00:47:57 -05:00
129 lines
4.6 KiB
Python
129 lines
4.6 KiB
Python
"""
|
|
/***************************************************************************
|
|
Name : DB Manager
|
|
Description : Database manager plugin for QGIS
|
|
Date : May 23, 2011
|
|
copyright : (C) 2011 by Giuseppe Sucameli
|
|
email : brush.tyler@gmail.com
|
|
|
|
***************************************************************************/
|
|
|
|
/***************************************************************************
|
|
* *
|
|
* This program is free software; you can redistribute it and/or modify *
|
|
* it under the terms of the GNU General Public License as published by *
|
|
* the Free Software Foundation; either version 2 of the License, or *
|
|
* (at your option) any later version. *
|
|
* *
|
|
***************************************************************************/
|
|
"""
|
|
|
|
from qgis.PyQt.QtCore import Qt, QTimer
|
|
from qgis.PyQt.QtGui import QColor, QCursor
|
|
from qgis.PyQt.QtWidgets import QApplication
|
|
|
|
from qgis.gui import QgsMapCanvas, QgsMessageBar
|
|
from qgis.core import Qgis, QgsVectorLayer, QgsProject, QgsSettings
|
|
from qgis.utils import OverrideCursor
|
|
|
|
from .db_plugins.plugin import Table
|
|
|
|
|
|
class LayerPreview(QgsMapCanvas):
|
|
|
|
def __init__(self, parent=None):
|
|
super().__init__(parent)
|
|
self.parent = parent
|
|
self.setCanvasColor(QColor(255, 255, 255))
|
|
|
|
self.item = None
|
|
self.dirty = False
|
|
self.current_layer = None
|
|
|
|
# reuse settings from QGIS
|
|
settings = QgsSettings()
|
|
self.enableAntiAliasing(settings.value("/qgis/enable_anti_aliasing", False, type=bool))
|
|
zoomFactor = settings.value("/qgis/zoom_factor", 2, type=float)
|
|
self.setWheelFactor(zoomFactor)
|
|
|
|
def refresh(self):
|
|
self.setDirty(True)
|
|
self.loadPreview(self.item)
|
|
|
|
def loadPreview(self, item):
|
|
if item == self.item and not self.dirty:
|
|
return
|
|
|
|
if item is None:
|
|
return
|
|
|
|
self._clear()
|
|
|
|
if isinstance(item, Table) and item.type in [Table.VectorType, Table.RasterType]:
|
|
# update the preview, but first let the manager chance to show the canvas
|
|
def runPrev():
|
|
return self._loadTablePreview(item)
|
|
|
|
QTimer.singleShot(50, runPrev)
|
|
else:
|
|
return
|
|
|
|
self.item = item
|
|
self.item.aboutToChange.connect(self.setDirty)
|
|
|
|
def setDirty(self, val=True):
|
|
self.dirty = val
|
|
|
|
def _clear(self):
|
|
""" remove any layers from preview canvas """
|
|
if self.item is not None:
|
|
# skip exception on RuntimeError fixes #6892
|
|
try:
|
|
self.item.aboutToChange.disconnect(self.setDirty)
|
|
except RuntimeError:
|
|
pass
|
|
|
|
self.item = None
|
|
self.dirty = False
|
|
self._loadTablePreview(None)
|
|
|
|
def _loadTablePreview(self, table, limit=False):
|
|
""" if has geometry column load to map canvas """
|
|
with OverrideCursor(Qt.CursorShape.WaitCursor):
|
|
self.freeze()
|
|
vl = None
|
|
|
|
if table and table.geomType:
|
|
# limit the query result if required
|
|
if limit and table.rowCount > 1000:
|
|
uniqueField = table.getValidQgisUniqueFields(True)
|
|
if uniqueField is None:
|
|
self.parent.tabs.setCurrentWidget(self.parent.info)
|
|
self.parent.infoBar.pushMessage(
|
|
QApplication.translate("DBManagerPlugin", "Unable to find a valid unique field"),
|
|
Qgis.MessageLevel.Warning, self.parent.iface.messageTimeout())
|
|
return
|
|
|
|
uri = table.database().uri()
|
|
uri.setDataSource("", "(SELECT * FROM %s LIMIT 1000)" % table.quotedName(), table.geomColumn, "",
|
|
uniqueField.name)
|
|
provider = table.database().dbplugin().providerName()
|
|
vl = QgsVectorLayer(uri.uri(False), table.name, provider)
|
|
else:
|
|
vl = table.toMapLayer()
|
|
|
|
if vl and not vl.isValid():
|
|
vl.deleteLater()
|
|
vl = None
|
|
|
|
if vl and vl.isValid():
|
|
self.current_layer = vl
|
|
self.setLayers([self.current_layer])
|
|
self.zoomToFullExtent()
|
|
else:
|
|
self.setLayers([])
|
|
self.current_layer = None
|
|
|
|
self.freeze(False)
|
|
super().refresh()
|