Add dropdown button to select from list of text strings.

linkcheck/gui/lineedit.py

@@ -18,11 +18,21 @@
 from PyQt4 import QtCore, QtGui
 
 class LineEdit (QtGui.QLineEdit):
-    """A line edit widget displaying a clear button if there is some text."""
+    """A line edit widget displaying a clear button if there is some text
+    and a down-arrow button displaying a list of strings (eg. recent
+    documents)."""
 
     def __init__ (self, parent=None):
-        """Initialize the clear button."""
+        """Initialize buttons and size settings."""
         super(LineEdit, self).__init__(parent)
+        self.listmodel = None
+        self.listview = None
+        self.setup_clear_button()
+        self.setup_list_button()
+        self.setup_size_metrics()
+
+    def setup_clear_button (self):
+        """Initialize the clear button."""
         self.clearButton = QtGui.QToolButton(self)
         pixmap = QtGui.QPixmap(":/icons/clear.png")
         self.clearButton.setIcon(QtGui.QIcon(pixmap))
@@ -33,27 +43,133 @@ class LineEdit (QtGui.QLineEdit):
         self.clearButton.hide()
         self.clearButton.clicked.connect(self.clear)
         self.textChanged.connect(self.updateCloseButton)
+
+    def setup_list_button (self):
+        """Initialize the dropdown list button."""
+        self.listButton = QtGui.QToolButton(self)
+        pixmap = QtGui.QPixmap(":/icons/arrow_down.png")
+        self.listButton.setIcon(QtGui.QIcon(pixmap))
+        self.listButton.setIconSize(pixmap.size())
+        self.listButton.setCursor(QtCore.Qt.ArrowCursor)
+        style = "QToolButton { border: none; padding: 0px; }"
+        self.listButton.setStyleSheet(style)
+        self.listButton.hide()
+        self.listButton.clicked.connect(self.toggle_list)
+
+    def setModel (self, model):
+        """Set list model for list of recent documents."""
+        self.listmodel = model
+        self.listview = QtGui.QListView()
+        self.listview.setModel(model)
+        self.listview.setWindowFlags(QtCore.Qt.Popup)
+        self.listview.setFocusPolicy(QtCore.Qt.NoFocus)
+        self.listview.setFocusProxy(self)
+        self.listview.setMouseTracking(True)
+        self.listview.setUniformItemSizes(True)
+        self.listview.setEditTriggers(QtGui.QAbstractItemView.NoEditTriggers)
+        self.listview.setSelectionBehavior(QtGui.QAbstractItemView.SelectRows)
+        self.listview.setFrameStyle(QtGui.QFrame.Box | QtGui.QFrame.Plain)
+        self.listview.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
+        self.listview.installEventFilter(self)
+        self.listview.clicked.connect(self.selectRecentDocument)
+        self.listview.hide()
+        updatefunc = lambda parent, start, end: self.updateListButton
+        self.listmodel.rowsInserted.connect(updatefunc)
+        self.listmodel.rowsRemoved.connect(updatefunc)
+        self.updateListButton()
+
+    def eventFilter(self, obj, event):
+        """Handle events from the listview popup."""
+        if obj != self.listview:
+            return False
+
+        if event.type() == QtCore.QEvent.MouseButtonPress:
+            self.listview.hide()
+            self.setFocus()
+            return True
+
+        if event.type() == QtCore.QEvent.KeyPress:
+            consumed = False
+            key = event.key()
+            if key in (QtCore.Qt.Key_Enter, QtCore.Qt.Key_Return):
+                self.doneCompletion()
+                consumed = True
+            elif key == QtCore.Qt.Key_Escape:
+                self.setFocus()
+                self.listview.hide()
+                consumed = True
+            elif key in (QtCore.Qt.Key_Up, QtCore.Qt.Key_Down,
+                         QtCore.Qt.Key_Home, QtCore.Qt.Key_End,
+                         QtCore.Qt.Key_PageUp, QtCore.Qt.Key_PageDown):
+                pass
+            else:
+                self.setFocus()
+                self.event(event)
+                self.listview.hide()
+            return consumed
+        return False
+
+    def selectRecentDocument (self, index):
+        """Select recent document text after click on the list view."""
+        self.listview.hide()
+        item = self.listmodel.data(index)
+        text = unicode(item.toString())
+        self.setText(text)
+
+    def setup_size_metrics (self):
+        """Set widget size including the buttons."""
         frameWidth = self.style().pixelMetric(QtGui.QStyle.PM_DefaultFrameWidth)
-        padding = self.clearButton.sizeHint().width() + frameWidth + 1
-        self.setStyleSheet("QLineEdit { padding-right: %dpx; } " % padding)
-        mSize = self.minimumSizeHint()
-        sizeHint = self.clearButton.sizeHint()
-        mWidth = max(mSize.width(), sizeHint.width() + frameWidth * 2 + 2)
-        mHeight = max(mSize.height(), sizeHint.height() + frameWidth * 2 + 2)
-        self.setMinimumSize(mWidth, mHeight)
+        padding_right = self.clearButton.sizeHint().width() + frameWidth + 1
+        padding_left = self.listButton.sizeHint().width() + frameWidth + 1
+        style = "QLineEdit { padding-left: %dpx; padding-right: %dpx } " % (
+          padding_left, padding_right)
+        self.setStyleSheet(style)
+        # minimum width
+        minSize = self.minimumSizeHint()
+        buttonWidth = padding_left + padding_right
+        minWidth = max(minSize.width(), buttonWidth)
+        # minimum height
+        buttonHeight = max(self.clearButton.sizeHint().height(),
+                           self.listButton.sizeHint().height())
+        minHeight = max(minSize.height(), buttonHeight + frameWidth*2)
+        # set minimum size
+        self.setMinimumSize(minWidth, minHeight)
 
     def resizeEvent (self, event):
-        """Move the clear button due to resize event."""
-        sizeHint = self.clearButton.sizeHint()
+        """Move the buttons due to resize event."""
         frameWidth = self.style().pixelMetric(QtGui.QStyle.PM_DefaultFrameWidth)
+        bottom = self.rect().y() + self.rect().height()
+        # clear button
+        sizeHint = self.clearButton.sizeHint()
         x = self.rect().right() - frameWidth - sizeHint.width()
-        y = (self.rect().bottom() + 1 - sizeHint.height())/2
+        y = (bottom - sizeHint.height()) / 2
         self.clearButton.move(x,y)
+        # list button
+        sizeHint = self.listButton.sizeHint()
+        # add one to x and y since the button icon is a little off
+        x = self.rect().left() + frameWidth + 1
+        y = (bottom - sizeHint.height()) / 2 + 1
+        self.listButton.move(x,y)
+
+    def updateListButton (self):
+        """Show or hide button for list of documents."""
+        self.listButton.setVisible(bool(self.listmodel.rowCount()))
 
     def updateCloseButton (self, text):
         """Only display the clear button if there is some text."""
         self.clearButton.setVisible(bool(text))
 
+    def toggle_list (self):
+        """Show or hide list of documents."""
+        if self.listview.isHidden():
+            self.listview.adjustSize()
+            point = self.mapToGlobal(QtCore.QPoint(0, self.height()))
+            self.listview.move(point)
+            self.listview.setFocus()
+            self.listview.show()
+        else:
+            self.listview.hide()
+
     def contextMenuEvent (self, event):
         """Add Firefox bookmark action to context menu."""
         menu = self.createStandardContextMenu()