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</o:shapelayout></xml><![endif]--></head><body lang=PT-BR link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I think in this case, as you do not want to close your gui, you should put the message bar in your gui, I suppose it's a dialog.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>you have a code sample in <a href="https://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/communicating.html">Qgis cookbook</a>, may it can help you:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'>class MyDialog(QDialog):<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> def __init__(self):<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> QDialog.__init__(self)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.bar = QgsMessageBar()<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.bar.setSizePolicy( QSizePolicy.Minimum, QSizePolicy.Fixed )<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.setLayout(QGridLayout())<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.layout().setContentsMargins(0, 0, 0, 0)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.buttonbox = QDialogButtonBox(QDialogButtonBox.Ok)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.buttonbox.accepted.connect(self.run)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.layout().addWidget(self.buttonbox, 0, 0, 2, 1)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.layout().addWidget(self.bar, 0, 0, 1, 1)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> def run(self):<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Courier New"'> self.bar.pushMessage("Hello", "World", level=Qgis.Info)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> QGIS-Developer [mailto:qgis-developer-bounces@lists.osgeo.org] <b>Em nome de </b>Roberta Fagandini<br><b>Enviada em:</b> sexta-feira, 3 de maio de 2019 10:45<br><b>Para:</b> qgis-developer@lists.osgeo.org<br><b>Assunto:</b> [QGIS-Developer] show error message without exiting the plugin<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Hi all,<o:p></o:p></p><div><p class=MsoNormal>I'm developing a plugin and I need to check if some features of the input vector layer are selected or not. If not I'd like to show an error message without closing the plugin gui:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>This is the code at the moment:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal> if self.dlg.checkBox.isChecked():<o:p></o:p></p></div><div><p class=MsoNormal> check_sel = selectedLayer2.selectedFeatureCount()<o:p></o:p></p></div><div><p class=MsoNormal> if check_sel > 0:<o:p></o:p></p></div><div><p class=MsoNormal> intersec_layer = QgsProcessingFeatureSourceDefinition(selectedLayer2.id(), True)<o:p></o:p></p></div><div><p class=MsoNormal> else:<o:p></o:p></p></div><div><p class=MsoNormal> self.iface.messageBar().pushCritical("Error", "No features selected in layer {}.".format(selectedLayer2.name()))<o:p></o:p></p></div><div><p class=MsoNormal> return <o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Any idea?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks<o:p></o:p></p></div><div><p class=MsoNormal>Roberta<o:p></o:p></p></div></div></div></div></body></html>