From a999821ad46ac19fae34fec78d538423ff6e5adc Mon Sep 17 00:00:00 2001 From: that Date: Thu, 19 Feb 2015 22:51:24 +0100 Subject: gui: proportional scrollbars - Attribute "recth" in the element is now the *minimum* height for the scrollbar. - Dragging the scrollbar moves the list. - Touching outside the scrollbar jumps to the relative position. Change-Id: Ic1f20b5ec68cf49e5be56be34f0c58c0f474618b --- gui/scrolllist.cpp | 107 ++++++++++++++++++++++++++++------------------------- 1 file changed, 56 insertions(+), 51 deletions(-) (limited to 'gui/scrolllist.cpp') diff --git a/gui/scrolllist.cpp b/gui/scrolllist.cpp index 4b772d45d..70a54e5ac 100644 --- a/gui/scrolllist.cpp +++ b/gui/scrolllist.cpp @@ -44,6 +44,7 @@ GUIScrollList::GUIScrollList(xml_node<>* node) : GUIObject(node) mFont = NULL; mBackgroundW = mBackgroundH = 0; mFastScrollW = mFastScrollLineW = mFastScrollRectW = mFastScrollRectH = 0; + mFastScrollRectCurrentY = mFastScrollRectCurrentH = mFastScrollRectTouchY = 0; lastY = last2Y = fastScroll = 0; mUpdate = 0; touchDebounce = 6; @@ -284,7 +285,7 @@ int GUIScrollList::Render(void) yPos += actualItemHeight; } - // Render the Header (last so that it overwrites the top most row for per pixel scrolling) + // Render the Header yPos = mRenderY; if (mHeaderH > 0) { // First step, fill background @@ -310,35 +311,41 @@ int GUIScrollList::Render(void) gr_fill(mRenderX, yPos + mHeaderH - mHeaderSeparatorH, mRenderW, mHeaderSeparatorH); } + // reset clipping + gr_noclip(); + // render fast scroll - lines = GetDisplayItemCount(); if (hasScroll) { - int startX = listW + mRenderX; int fWidth = mRenderW - listW; int fHeight = mRenderH - mHeaderH; + int centerX = listW + mRenderX + fWidth / 2; - // line - gr_color(mFastScrollLineColor.red, mFastScrollLineColor.green, mFastScrollLineColor.blue, mFastScrollLineColor.alpha); - gr_fill(startX + fWidth/2, mRenderY + mHeaderH, mFastScrollLineW, mRenderH - mHeaderH); + // first determine the total list height and where we are in the list + int totalHeight = GetItemCount() * actualItemHeight; // total height of the full list in pixels + int topPos = firstDisplayedItem * actualItemHeight - y_offset; - // rect - int pct = 0; - if (GetDisplayRemainder() != 0) { - // Properly handle the percentage if a partial line is present - int partial_line_size = actualItemHeight - GetDisplayRemainder(); - pct = ((firstDisplayedItem*actualItemHeight - y_offset)*100)/(listSize*actualItemHeight-((lines + 1)*actualItemHeight) + partial_line_size); - } else { - pct = ((firstDisplayedItem*actualItemHeight - y_offset)*100)/(listSize*actualItemHeight-lines*actualItemHeight); - } - int mFastScrollRectX = startX + (fWidth - mFastScrollRectW)/2; - int mFastScrollRectY = mRenderY+mHeaderH + ((fHeight - mFastScrollRectH)*pct)/100; + // now scale it proportionally to the scrollbar height + int boxH = fHeight * fHeight / totalHeight; // proportional height of the displayed portion + boxH = std::max(boxH, mFastScrollRectH); // but keep a minimum height + int boxY = (fHeight - boxH) * topPos / (totalHeight - fHeight); // pixels relative to top of list + int boxW = mFastScrollRectW; + + int x = centerX - boxW / 2; + int y = mRenderY + mHeaderH + boxY; + + // line above and below box (needs to be split because box can be transparent) + gr_color(mFastScrollLineColor.red, mFastScrollLineColor.green, mFastScrollLineColor.blue, mFastScrollLineColor.alpha); + gr_fill(centerX - mFastScrollLineW / 2, mRenderY + mHeaderH, mFastScrollLineW, boxY); + gr_fill(centerX - mFastScrollLineW / 2, y + boxH, mFastScrollLineW, fHeight - boxY - boxH); + // box gr_color(mFastScrollRectColor.red, mFastScrollRectColor.green, mFastScrollRectColor.blue, mFastScrollRectColor.alpha); - gr_fill(mFastScrollRectX, mFastScrollRectY, mFastScrollRectW, mFastScrollRectH); + gr_fill(x, y, boxW, boxH); + + mFastScrollRectCurrentY = boxY; + mFastScrollRectCurrentH = boxH; } mUpdate = 0; - // reset clipping - gr_noclip(); return 0; } @@ -416,8 +423,20 @@ int GUIScrollList::NotifyTouch(TOUCH_STATE state, int x, int y) switch (state) { case TOUCH_START: - if (hasScroll && x >= mRenderX + mRenderW - mFastScrollW) + if (hasScroll && x >= mRenderX + mRenderW - mFastScrollW) { fastScroll = 1; // Initial touch is in the fast scroll region + int fastScrollBoxTop = mFastScrollRectCurrentY + mRenderY + mHeaderH; + int fastScrollBoxBottom = fastScrollBoxTop + mFastScrollRectCurrentH; + if (y >= fastScrollBoxTop && y < fastScrollBoxBottom) + // user grabbed the fastscroll bar + // try to keep the initially touched part of the scrollbar under the finger + mFastScrollRectTouchY = y - fastScrollBoxTop; + else + // user tapped outside the fastscroll bar + // center fastscroll rect on the initial touch position + mFastScrollRectTouchY = mFastScrollRectCurrentH / 2; + } + if (scrollingSpeed != 0) { selectedItem = NO_ITEM; // this allows the user to tap the list to stop the scrolling without selecting the item they tap scrollingSpeed = 0; // stop scrolling on a new touch @@ -433,36 +452,20 @@ int GUIScrollList::NotifyTouch(TOUCH_STATE state, int x, int y) case TOUCH_DRAG: if (fastScroll) { - int pct = ((y-mRenderY-mHeaderH)*100)/(mRenderH-mHeaderH); - int totalSize = GetItemCount(); - int lines = GetDisplayItemCount(); - - float l = float((totalSize-lines)*pct)/100; - if(l + lines >= totalSize) - { - firstDisplayedItem = totalSize - lines; - if (GetDisplayRemainder() != 0) { - // There's a partial row displayed, set the scrolling offset so that the last item really is at the very bottom - firstDisplayedItem--; - y_offset = GetDisplayRemainder() - actualItemHeight; - } else { - // There's no partial row so zero out the offset - y_offset = 0; - } - } - else - { - if (l < 0) - l = 0; - firstDisplayedItem = l; - y_offset = -(l - int(l))*actualItemHeight; - if (GetDisplayRemainder() != 0) { - // There's a partial row displayed, make sure y_offset doesn't go past the max - if (firstDisplayedItem == totalSize - lines - 1 && y_offset < GetDisplayRemainder() - actualItemHeight) - y_offset = GetDisplayRemainder() - actualItemHeight; - } else if (firstDisplayedItem == totalSize - lines) - y_offset = 0; - } + int relY = y - mRenderY - mHeaderH; // touch position relative to window + int windowH = mRenderH - mHeaderH; + int totalHeight = GetItemCount() * actualItemHeight; // total height of the full list in pixels + + // calculate new top position of the fastscroll bar relative to window + int newY = relY - mFastScrollRectTouchY; + // keep it fully inside the list + newY = std::min(std::max(newY, 0), windowH - mFastScrollRectCurrentH); + + // now compute the new scroll position for the list + int newTopPos = newY * (totalHeight - windowH) / (windowH - mFastScrollRectCurrentH); // new top pixel of list + newTopPos = std::min(newTopPos, totalHeight - windowH); // account for rounding errors + firstDisplayedItem = newTopPos / actualItemHeight; + y_offset = - newTopPos % actualItemHeight; selectedItem = NO_ITEM; mUpdate = 1; @@ -490,6 +493,8 @@ int GUIScrollList::NotifyTouch(TOUCH_STATE state, int x, int y) break; case TOUCH_RELEASE: + if (fastScroll) + mUpdate = 1; // get rid of touch effects on the fastscroll bar fastScroll = 0; if (selectedItem != NO_ITEM) { // We've selected an item! -- cgit v1.2.3