Don't clip the cursor at the far right of a TextInput.

The cursor is allowed to exceed the boundaries of a TextInput so that
the text alignment is consistent with the Text element and the bounding
rect of TextInput is expanded to allow for that.  To avoid clipping
the contentSize also needs to be expanded, and the horizontal scrolling
should be calculated against the non-expanded size.

Task-number: QTBUG-18818
Change-Id: I09e3a7aff9c2e8a333e8a3f9796683563b3e124a
Reviewed-on: http://codereview.qt.nokia.com/2242
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Martin Jones <martin.jones@nokia.com>

1 files changed, 26 insertions, 45 deletions

diff --git a/src/declarative/items/qsgtextinput.cpp b/src/declarative/items/qsgtextinput.cpp
index fe7070548b..eb5e23187c 100644
--- a/src/declarative/items/qsgtextinput.cpp
+++ b/src/declarative/items/qsgtextinput.cpp
@@ -784,36 +784,36 @@ void QSGTextInputPrivate::updateHorizontalScroll()
 {
     Q_Q(QSGTextInput);
     const int preeditLength = control->preeditAreaText().length();
-    int cix = qRound(control->cursorToX(control->cursor() + preeditLength));
-    QRect br(q->boundingRect().toRect());
+    const int width = q->width();
     int widthUsed = calculateTextWidth();
 
-    QSGTextInput::HAlignment effectiveHAlign = q->effectiveHAlign();
-    if (autoScroll) {
-        if (widthUsed <=  br.width()) {
-            // text fits in br; use hscroll for alignment
-            switch (effectiveHAlign & ~(Qt::AlignAbsolute|Qt::AlignVertical_Mask)) {
-            case Qt::AlignRight:
-                hscroll = widthUsed - br.width() - 1;
-                break;
-            case Qt::AlignHCenter:
-                hscroll = (widthUsed - br.width()) / 2;
-                break;
-            default:
-                // Left
-                hscroll = 0;
-                break;
-            }
-        } else if (cix - hscroll >= br.width()) {
+    if (!autoScroll || widthUsed <=  width) {
+        QSGTextInput::HAlignment effectiveHAlign = q->effectiveHAlign();
+        // text fits in br; use hscroll for alignment
+        switch (effectiveHAlign & ~(Qt::AlignAbsolute|Qt::AlignVertical_Mask)) {
+        case Qt::AlignRight:
+            hscroll = widthUsed - width;
+            break;
+        case Qt::AlignHCenter:
+            hscroll = (widthUsed - width) / 2;
+            break;
+        default:
+            // Left
+            hscroll = 0;
+            break;
+        }
+    } else {
+        int cix = qRound(control->cursorToX(control->cursor() + preeditLength));
+        if (cix - hscroll >= width) {
             // text doesn't fit, cursor is to the right of br (scroll right)
-            hscroll = cix - br.width() + 1;
+            hscroll = cix - width;
         } else if (cix - hscroll < 0 && hscroll < widthUsed) {
             // text doesn't fit, cursor is to the left of br (scroll left)
             hscroll = cix;
-        } else if (widthUsed - hscroll < br.width()) {
+        } else if (widthUsed - hscroll < width) {
             // text doesn't fit, text document is to the left of br; align
             // right
-            hscroll = widthUsed - br.width() + 1;
+            hscroll = widthUsed - width;
         }
         if (preeditLength > 0) {
             // check to ensure long pre-edit text doesn't push the cursor
@@ -823,26 +823,13 @@ void QSGTextInputPrivate::updateHorizontalScroll()
              if (cix < hscroll)
                  hscroll = cix;
         }
-    } else {
-        switch (effectiveHAlign) {
-        case QSGTextInput::AlignRight:
-            hscroll = q->width() - widthUsed;
-            break;
-        case QSGTextInput::AlignHCenter:
-            hscroll = (q->width() - widthUsed) / 2;
-            break;
-        default:
-            // Left
-            hscroll = 0;
-            break;
-        }
     }
 }
 
 void QSGTextInput::paint(QPainter *p)
 {
     // XXX todo
-    QRect r(0, 0, width(), height());
+    QRect r = boundingRect().toRect();
 
     Q_D(QSGTextInput);
     p->setRenderHint(QPainter::TextAntialiasing, true);
@@ -853,15 +840,9 @@ void QSGTextInput::paint(QPainter *p)
         flags |= QLineControl::DrawCursor;
     if (d->control->hasSelectedText())
             flags |= QLineControl::DrawSelections;
-    QPoint offset = QPoint(0,0);
     QFontMetrics fm = QFontMetrics(d->font);
-    QRect br(boundingRect().toRect());
-    if (d->autoScroll) {
-        // the y offset is there to keep the baseline constant in case we have script changes in the text.
-        offset = br.topLeft() - QPoint(d->hscroll, d->control->ascent() - fm.ascent());
-    } else {
-        offset = QPoint(d->hscroll, 0);
-    }
+    // the y offset is there to keep the baseline constant in case we have script changes in the text.
+    QPoint offset(-d->hscroll, fm.ascent() - d->control->ascent());
     d->control->draw(p, offset, r, flags);
     p->restore();
 }
@@ -1262,7 +1243,7 @@ void QSGTextInput::updateSize(bool needsRedraw)
     int h = height();
     setImplicitHeight(d->control->height()-1); // -1 to counter QLineControl's +1 which is not consistent with Text.
     setImplicitWidth(d->calculateTextWidth());
-    setContentsSize(QSize(width(), height()));
+    setContentsSize(boundingRect().size().toSize());
     if(w==width() && h==height() && needsRedraw)
         update();
 }