Allow hiding clear button in QgsFilterLineEdit

(cherry-pick from d959384)

python/gui/qgsfilterlineedit.sip

@@ -27,15 +27,30 @@ class QgsFilterLineEdit : QLineEdit
      */
     QgsFilterLineEdit( QWidget* parent /TransferThis/ = 0, const QString& nullValue = QString::null );
 
+    /** Returns true if the widget's clear button is visible.
+     * @see setShowClearButton()
+     * @note added in QGIS 3.0
+     */
+    bool showClearButton() const;
+
+    /** Sets whether the widget's clear button is visible.
+     * @param visible set to false to hide the clear button
+     * @see showClearButton()
+     * @note added in QGIS 3.0
+     */
+    void setShowClearButton( bool visible );
+
     /** Returns the clear mode for the widget. The clear mode defines the behaviour of the
      * widget when its value is cleared. This defaults to ClearToNull.
      * @see setClearMode()
+     * @note added in QGIS 3.0
      */
     ClearMode clearMode() const;
 
     /** Sets the clear mode for the widget. The clear mode defines the behaviour of the
      * widget when its value is cleared. This defaults to ClearToNull.
      * @see clearMode()
+     * @note added in QGIS 3.0
      */
     void setClearMode( ClearMode mode );
 
@@ -59,6 +74,7 @@ class QgsFilterLineEdit : QLineEdit
      * @param defaultValue default value
      * @see defaultValue()
      * @see clearMode()
+     * @note added in QGIS 3.0
      */
     void setDefaultValue( const QString& defaultValue );
 
@@ -67,6 +83,7 @@ class QgsFilterLineEdit : QLineEdit
      * is equal to ClearToDefault.
      * @see setDefaultValue()
      * @see clearMode()
+     * @note added in QGIS 3.0
      */
     QString defaultValue() const;
 
@@ -101,6 +118,7 @@ class QgsFilterLineEdit : QLineEdit
 
     /** Clears the widget and resets it to the null value.
      * @see nullValue()
+     * @note added in QGIS 3.0
      */
     virtual void clearValue();
 

src/gui/qgsfilterlineedit.cpp

@@ -25,6 +25,7 @@
 
 QgsFilterLineEdit::QgsFilterLineEdit( QWidget* parent, const QString& nullValue )
     : QLineEdit( parent )
+    , mClearButtonVisible( true )
     , mClearMode( ClearToNull )
     , mNullValue( nullValue )
     , mFocusInEvent( false )
@@ -43,6 +44,15 @@ QgsFilterLineEdit::QgsFilterLineEdit( QWidget* parent, const QString& nullValue
            SLOT( onTextChanged( const QString& ) ) );
 }
 
+void QgsFilterLineEdit::setShowClearButton( bool visible )
+{
+  mClearButtonVisible = visible;
+  if ( !visible )
+    mClearHover = false;
+
+  update();
+}
+
 void QgsFilterLineEdit::mousePressEvent( QMouseEvent* e )
 {
   if ( !mFocusInEvent )
@@ -145,7 +155,7 @@ void QgsFilterLineEdit::onTextChanged( const QString &text )
 
 bool QgsFilterLineEdit::shouldShowClear() const
 {
-  if ( !isEnabled() || isReadOnly() )
+  if ( !isEnabled() || isReadOnly() || !mClearButtonVisible )
     return false;
 
   switch ( mClearMode )

src/gui/qgsfilterlineedit.h

@@ -39,6 +39,7 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
     Q_PROPERTY( QString nullValue READ nullValue WRITE setNullValue )
     Q_PROPERTY( QString defaultValue READ defaultValue WRITE setDefaultValue )
     Q_PROPERTY( QString value READ value WRITE setValue NOTIFY valueChanged )
+    Q_PROPERTY( bool showClearButton READ showClearButton WRITE setShowClearButton )
 
   public:
 
@@ -55,15 +56,30 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
      */
     QgsFilterLineEdit( QWidget* parent = nullptr, const QString& nullValue = QString::null );
 
+    /** Returns true if the widget's clear button is visible.
+     * @see setShowClearButton()
+     * @note added in QGIS 3.0
+     */
+    bool showClearButton() const { return mClearButtonVisible; }
+
+    /** Sets whether the widget's clear button is visible.
+     * @param visible set to false to hide the clear button
+     * @see showClearButton()
+     * @note added in QGIS 3.0
+     */
+    void setShowClearButton( bool visible );
+
     /** Returns the clear mode for the widget. The clear mode defines the behaviour of the
      * widget when its value is cleared. This defaults to ClearToNull.
      * @see setClearMode()
+     * @note added in QGIS 3.0
      */
     ClearMode clearMode() const { return mClearMode; }
 
     /** Sets the clear mode for the widget. The clear mode defines the behaviour of the
      * widget when its value is cleared. This defaults to ClearToNull.
      * @see clearMode()
+     * @note added in QGIS 3.0
      */
     void setClearMode( ClearMode mode ) { mClearMode = mode; }
 
@@ -87,6 +103,7 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
      * @param defaultValue default value
      * @see defaultValue()
      * @see clearMode()
+     * @note added in QGIS 3.0
      */
     void setDefaultValue( const QString& defaultValue ) { mDefaultValue = defaultValue; }
 
@@ -95,6 +112,7 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
      * is equal to ClearToDefault.
      * @see setDefaultValue()
      * @see clearMode()
+     * @note added in QGIS 3.0
      */
     QString defaultValue() const { return mDefaultValue; }
 
@@ -129,6 +147,7 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
 
     /** Clears the widget and resets it to the null value.
      * @see nullValue()
+     * @note added in QGIS 3.0
      */
     virtual void clearValue();
 
@@ -158,6 +177,8 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
 
   private:
 
+    bool mClearButtonVisible;
+
     ClearMode mClearMode;
 
     QString mNullValue;

tests/src/python/test_qgsfilterlineedit.py

@@ -42,6 +42,10 @@ def testGettersSetters(self):
         self.assertEqual(w.defaultValue(), 'default')
         w.setClearMode(QgsFilterLineEdit.ClearToDefault)
         self.assertEqual(w.clearMode(), QgsFilterLineEdit.ClearToDefault)
+        w.setShowClearButton(False)
+        self.assertFalse(w.showClearButton())
+        w.setShowClearButton(True)
+        self.assertTrue(w.showClearButton())
 
     def testNullValueHandling(self):
         """ test widget handling of null values """