option to show a search icon in QgsFilterLineEdit

images/images.qrc

@@ -554,6 +554,7 @@
         <file>themes/default/processingModel.svg</file>
         <file>themes/default/processingScript.svg</file>
         <file>themes/default/processingAlgorithm.svg</file>
+        <file>themes/default/search.svg</file>
     </qresource>
     <qresource prefix="/images/tips">
         <file alias="symbol_levels.png">qgis_tips/symbol_levels.png</file>

images/themes/default/search.svg

@@ -0,0 +1,66 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   height="16"
+   version="1.1"
+   viewBox="0 0 16 16"
+   width="16"
+   id="svg2"
+   inkscape:version="0.91 r13725"
+   sodipodi:docname="search.svg">
+  <metadata
+     id="metadata15">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <sodipodi:namedview
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1"
+     objecttolerance="10"
+     gridtolerance="10"
+     guidetolerance="10"
+     inkscape:pageopacity="0"
+     inkscape:pageshadow="2"
+     inkscape:window-width="1732"
+     inkscape:window-height="977"
+     id="namedview13"
+     showgrid="false"
+     inkscape:zoom="11.313708"
+     inkscape:cx="3.1800974"
+     inkscape:cy="-12.185144"
+     inkscape:window-x="414"
+     inkscape:window-y="64"
+     inkscape:window-maximized="0"
+     inkscape:current-layer="svg2" />
+  <desc
+     id="desc6" />
+  <defs
+     id="defs8" />
+  <g
+     id="Page-1"
+     style="fill:none;fill-rule:evenodd;stroke:none;stroke-width:1"
+     transform="matrix(0.56015021,0,0,0.56015021,-1.3609013,-1.3602825)">
+    <g
+       id="icon-111-search"
+       style="fill:#929292">
+      <path
+         d="M 19.427116,21.427116 C 18.03725,22.41748 16.336652,23 14.5,23 9.8055794,23 6,19.194421 6,14.5 6,9.8055794 9.8055794,6 14.5,6 c 4.694421,0 8.5,3.8055794 8.5,8.5 0,1.836652 -0.58252,3.53725 -1.572884,4.927116 l 5.584802,5.584802 c 0.550201,0.550201 0.545613,1.430551 -2e-4,1.976363 l -0.02344,0.02344 c -0.544416,0.544417 -1.430661,0.545902 -1.976363,2e-4 l -5.584802,-5.584802 0,0 z M 14.5,21 C 18.089851,21 21,18.089851 21,14.5 21,10.910149 18.089851,8 14.5,8 10.910149,8 8,10.910149 8,14.5 8,18.089851 10.910149,21 14.5,21 l 0,0 z"
+         id="search"
+         inkscape:connector-curvature="0" />
+    </g>
+  </g>
+</svg>

python/gui/qgsfilterlineedit.sip

@@ -68,6 +68,19 @@ class QgsFilterLineEdit : QLineEdit
      */
     QString nullValue() const;
 
+    /** Define if a search icon shall be shown on the left of the image
+     * when no text is entered
+     * @param visible set to false to hide the search icon
+     * @note added in QGIS 3.0
+     */
+    void setShowSearchIcon( bool visible );
+
+    /** Returns if a search icon shall be shown on the left of the image
+     * when no text is entered
+     * @note added in QGIS 3.0
+     */
+    bool showSearchIcon() const;
+
     /** Sets the default value for the widget. The default value is a value
      * which the widget will be reset to if it is cleared and the clearMode()
      * is equal to ClearToDefault.

src/gui/qgsfilterlineedit.cpp

@@ -26,6 +26,7 @@
 QgsFilterLineEdit::QgsFilterLineEdit( QWidget* parent, const QString& nullValue )
     : QLineEdit( parent )
     , mClearButtonVisible( true )
+    , mSearchIconVisible( false )
     , mClearMode( ClearToNull )
     , mNullValue( nullValue )
     , mFocusInEvent( false )
@@ -40,6 +41,10 @@ QgsFilterLineEdit::QgsFilterLineEdit( QWidget* parent, const QString& nullValue
   QIcon hoverIcon = QgsApplication::getThemeIcon( "/mIconClearTextHover.svg" );
   mClearHoverPixmap = hoverIcon.pixmap( mClearIconSize );
 
+  QIcon searchIcon = QgsApplication::getThemeIcon( "/search.svg" );
+  mSearchIconSize = QSize( 16, 16 );
+  mSearchIconPixmap = searchIcon.pixmap( mSearchIconSize );
+
   connect( this, SIGNAL( textChanged( const QString& ) ), this,
            SLOT( onTextChanged( const QString& ) ) );
 }
@@ -55,6 +60,16 @@ void QgsFilterLineEdit::setShowClearButton( bool visible )
     update();
 }
 
+void QgsFilterLineEdit::setShowSearchIcon( bool visible )
+{
+  bool changed = mSearchIconVisible != visible;
+  if ( changed )
+  {
+    mSearchIconVisible = visible;
+    update();
+  }
+}
+
 void QgsFilterLineEdit::mousePressEvent( QMouseEvent* e )
 {
   if ( !mFocusInEvent )
@@ -134,6 +149,13 @@ void QgsFilterLineEdit::paintEvent( QPaintEvent* e )
     else
       p.drawPixmap( r.left() , r.top() , mClearIconPixmap );
   }
+
+  if ( mSearchIconVisible && !shouldShowClear() )
+  {
+    QRect r = searchRect();
+    QPainter p( this );
+    p.drawPixmap( r.left() , r.top() , mSearchIconPixmap );
+  }
 }
 
 void QgsFilterLineEdit::leaveEvent( QEvent* e )
@@ -191,3 +213,12 @@ QRect QgsFilterLineEdit::clearRect() const
                 mClearIconSize.width(),
                 mClearIconSize.height() );
 }
+
+QRect QgsFilterLineEdit::searchRect() const
+{
+  int frameWidth = style()->pixelMetric( QStyle::PM_DefaultFrameWidth );
+  return QRect( rect().left() + frameWidth * 2,
+                ( rect().bottom() + 1 - mSearchIconSize.height() ) / 2,
+                mSearchIconSize.width(),
+                mSearchIconSize.height() );
+}

src/gui/qgsfilterlineedit.h

@@ -41,6 +41,7 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
     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 )
+    Q_PROPERTY( bool showSearchIcon READ showSearchIcon WRITE setShowSearchIcon )
 
   public:
 
@@ -98,6 +99,19 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
      */
     QString nullValue() const { return mNullValue; }
 
+    /** Define if a search icon shall be shown on the left of the image
+     * when no text is entered
+     * @param visible set to false to hide the search icon
+     * @note added in QGIS 3.0
+     */
+    void setShowSearchIcon( bool visible );
+
+    /** Returns if a search icon shall be shown on the left of the image
+     * when no text is entered
+     * @note added in QGIS 3.0
+     */
+    bool showSearchIcon() const { return mSearchIconVisible; }
+
     /** Sets the default value for the widget. The default value is a value
      * which the widget will be reset to if it is cleared and the clearMode()
      * is equal to ClearToDefault.
@@ -179,6 +193,7 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
   private:
 
     bool mClearButtonVisible;
+    bool mSearchIconVisible;
 
     ClearMode mClearMode;
 
@@ -192,10 +207,14 @@ class GUI_EXPORT QgsFilterLineEdit : public QLineEdit
     QPixmap mClearIconPixmap;
     QPixmap mClearHoverPixmap;
 
+    QSize mSearchIconSize;
+    QPixmap mSearchIconPixmap;
+
     //! Returns true if clear button should be shown
     bool shouldShowClear() const;
 
     QRect clearRect() const;
+    QRect searchRect() const;
 };
 
 /// @cond PRIVATE