Updated formlayout to include the float validator

Author: gstorer

lib/matplotlib/backends/qt4_editor/formlayout.py

@@ -3,7 +3,7 @@
 formlayout
 ==========
 
-Module creating PyQt4 form dialogs/layouts to edit various type of parameters
+Module creating Qt form dialogs/layouts to edit various type of parameters
 
 
 formlayout License Agreement (MIT License)
@@ -34,10 +34,11 @@
 """
 
 # History:
+# 1.0.10: added float validator (disable "Ok" and "Apply" button when not valid)
 # 1.0.7: added support for "Apply" button
 # 1.0.6: code cleaning
 
-__version__ = '1.0.9'
+__version__ = '1.0.10'
 __license__ = __doc__
 
 DEBUG = False
@@ -53,14 +54,14 @@
  QDialogButtonBox, QHBoxLayout, QVBoxLayout, QDialog, QColor, QPushButton,
  QCheckBox, QColorDialog, QPixmap, QTabWidget, QApplication, QStackedWidget,
  QDateEdit, QDateTimeEdit, QFont, QFontComboBox, QFontDatabase, QGridLayout,
- QFormLayout) =\
+ QFormLayout, QDoubleValidator) =\
  (QtGui.QWidget, QtGui.QLineEdit, QtGui.QComboBox, QtGui.QLabel,
  QtGui.QSpinBox, QtGui.QIcon, QtGui.QStyle, QtGui.QDialogButtonBox,
  QtGui.QHBoxLayout, QtGui.QVBoxLayout, QtGui.QDialog, QtGui.QColor,
  QtGui.QPushButton, QtGui.QCheckBox, QtGui.QColorDialog, QtGui.QPixmap,
  QtGui.QTabWidget, QtGui.QApplication, QtGui.QStackedWidget, QtGui.QDateEdit,
  QtGui.QDateTimeEdit, QtGui.QFont, QtGui.QFontComboBox, QtGui.QFontDatabase,
- QtGui.QGridLayout, QtGui.QFormLayout)
+ QtGui.QGridLayout, QtGui.QFormLayout, QtGui.QDoubleValidator)
 
 (Qt, SIGNAL, SLOT, QObject, QSize,pyqtSignature, pyqtProperty) =\
 (QtCore.Qt, QtCore.SIGNAL, QtCore.SLOT, QtCore.QObject, QtCore.QSize, 
@@ -177,7 +178,6 @@ def qfont_to_tuple(font):
     return (unicode(font.family()), int(font.pointSize()),
             font.italic(), font.bold())
 
-
 class FontLayout(QGridLayout):
     """Font selection"""
     def __init__(self, value, parent=None):
@@ -220,9 +220,15 @@ def get_font(self):
         return qfont_to_tuple(font)
 
 
+def is_edit_valid(edit):
+    text = edit.text()
+    state = edit.validator().validate(text, 0)[0]
+	
+    return state == QDoubleValidator.Acceptable
+
 class FormWidget(QWidget):
     def __init__(self, data, comment="", parent=None):
-        super(FormWidget, self).__init__(parent)
+        QWidget.__init__(self, parent)
         from copy import deepcopy
         self.data = deepcopy(data)
         self.widgets = []
@@ -236,7 +242,13 @@ def __init__(self, data, comment="", parent=None):
             print "*"*80
             print "COMMENT:", comment
             print "*"*80
-        self.setup()
+            
+    def get_dialog(self):
+        """Return FormDialog instance"""
+        dialog = self.parent()
+        while not isinstance(dialog, QDialog):
+            dialog = dialog.parent()
+        return dialog
 
     def setup(self):
         for label, value in self.data:
@@ -284,6 +296,11 @@ def setup(self):
                     field.setCheckState(Qt.Unchecked)
             elif isinstance(value, float):
                 field = QLineEdit(repr(value), self)
+                field.setValidator(QDoubleValidator(field))
+                dialog = self.get_dialog()
+                dialog.register_float_field(field)
+                self.connect(field, SIGNAL('textChanged(QString)'),
+                             lambda text: dialog.update_buttons())
             elif isinstance(value, int):
                 field = QSpinBox(self)
                 field.setRange(-1e9, 1e9)
@@ -334,7 +351,7 @@ def get(self):
 
 class FormComboWidget(QWidget):
     def __init__(self, datalist, comment="", parent=None):
-        super(FormComboWidget, self).__init__(parent)
+        QWidget.__init__(self, parent)
         layout = QVBoxLayout()
         self.setLayout(layout)
         self.combobox = QComboBox()
@@ -351,14 +368,18 @@ def __init__(self, datalist, comment="", parent=None):
             widget = FormWidget(data, comment=comment, parent=self)
             self.stackwidget.addWidget(widget)
             self.widgetlist.append(widget)
+            
+    def setup(self):
+        for widget in self.widgetlist:
+            widget.setup()
 
     def get(self):
         return [ widget.get() for widget in self.widgetlist]
 
 
 class FormTabWidget(QWidget):
     def __init__(self, datalist, comment="", parent=None):
-        super(FormTabWidget, self).__init__(parent)
+        QWidget.__init__(self, parent)
         layout = QVBoxLayout()
         self.tabwidget = QTabWidget()
         layout.addWidget(self.tabwidget)
@@ -373,6 +394,10 @@ def __init__(self, datalist, comment="", parent=None):
             self.tabwidget.setTabToolTip(index, comment)
             self.widgetlist.append(widget)
 
+    def setup(self):
+        for widget in self.widgetlist:
+            widget.setup()
+            
     def get(self):
         return [ widget.get() for widget in self.widgetlist]
 
@@ -381,7 +406,7 @@ class FormDialog(QDialog):
     """Form Dialog"""
     def __init__(self, data, title="", comment="",
                  icon=None, parent=None, apply=None):
-        super(FormDialog, self).__init__(parent)
+        QDialog.__init__(self, parent)
 
         self.apply_callback = apply
 
@@ -398,8 +423,14 @@ def __init__(self, data, title="", comment="",
         layout = QVBoxLayout()
         layout.addWidget(self.formwidget)
 
+        self.float_fields = []
+        self.formwidget.setup()
+
         # Button box
-        bbox = QDialogButtonBox(QDialogButtonBox.Ok | QDialogButtonBox.Cancel)
+        self.bbox = bbox = QDialogButtonBox(QDialogButtonBox.Ok
+                                            |QDialogButtonBox.Cancel)
+        self.connect(self.formwidget, SIGNAL('update_buttons()'),
+                     self.update_buttons)
         if self.apply_callback is not None:
             apply_btn = bbox.addButton(QDialogButtonBox.Apply)
             self.connect(apply_btn, SIGNAL("clicked()"), self.apply)
@@ -414,6 +445,19 @@ def __init__(self, data, title="", comment="",
             icon = QWidget().style().standardIcon(QStyle.SP_MessageBoxQuestion)
         self.setWindowIcon(icon)
 
+    def register_float_field(self, field):
+        self.float_fields.append(field)
+        
+    def update_buttons(self):
+        valid = True
+        for field in self.float_fields:
+            if not is_edit_valid(field):
+                valid = False
+        for btn_type in (QDialogButtonBox.Ok, QDialogButtonBox.Apply):
+            btn = self.bbox.button(btn_type)
+            if btn is not None:
+                btn.setEnabled(valid)
+        
     def accept(self):
         self.data = self.formwidget.get()
         QDialog.accept(self)