Added ScrollWidget for scroll bars

1 files changed, 79 insertions, 0 deletions

diff --git a/src/ui/scrollwidget.c b/src/ui/scrollwidget.c
new file mode 100644
index 00000000..cbfd2e70
--- /dev/null
+++ b/src/ui/scrollwidget.c
@@ -0,0 +1,79 @@
+#include "scrollwidget.h"
+#include "paint.h"
+
+iDefineObjectConstruction(ScrollWidget)
+
+struct Impl_ScrollWidget {
+    iWidget widget;
+    iRangei range;
+    int thumb;
+    int thumbSize;
+};
+
+void init_ScrollWidget(iScrollWidget *d) {
+    iWidget *w = as_Widget(d);
+    init_Widget(w);
+    setId_Widget(w, "scroll");
+    setFlags_Widget(w,
+                    fixedWidth_WidgetFlag | resizeToParentHeight_WidgetFlag |
+                        moveToParentRightEdge_WidgetFlag,
+                    iTrue);
+    w->rect.size.x = gap_UI * 3;
+}
+
+void deinit_ScrollWidget(iScrollWidget *d) {
+    iUnused(d);
+}
+
+static iRect thumbRect_ScrollWidget_(const iScrollWidget *d) {
+    const iRect bounds = bounds_Widget(constAs_Widget(d));
+    iRect rect = init_Rect(bounds.pos.x, bounds.pos.y, bounds.size.x, 0);
+    const int total = size_Range(&d->range);
+//    printf("total: %d  thumb: %d  thsize: %d\n", total, d->thumb, d->thumbSize); fflush(stdout);
+    if (total > 0) {
+        const int tsize = iMax(gap_UI * 6, d->thumbSize);
+        const int tpos =
+            iClamp((float) d->thumb / (float) total, 0, 1) * (height_Rect(bounds) - tsize);
+        rect.pos.y  = tpos;
+        rect.size.y = tsize;
+    }
+    return rect;
+}
+
+static void checkVisible_ScrollWidget_(iScrollWidget *d) {
+    setFlags_Widget(as_Widget(d), hidden_WidgetFlag, height_Rect(thumbRect_ScrollWidget_(d)) == 0);
+}
+
+void setRange_ScrollWidget(iScrollWidget *d, iRangei range) {
+    range.end = iMax(range.start, range.end);
+    d->range = range;
+    checkVisible_ScrollWidget_(d);
+}
+
+void setThumb_ScrollWidget(iScrollWidget *d, int thumb, int thumbSize) {
+    d->thumb     = thumb;
+    d->thumbSize = thumbSize;
+    checkVisible_ScrollWidget_(d);
+}
+
+static iBool processEvent_ScrollWidget_(iScrollWidget *d, const SDL_Event *ev) {
+    iWidget *w = as_Widget(d);
+    return processEvent_Widget(w, ev);
+}
+
+static void draw_ScrollWidget_(const iScrollWidget *d) {
+    const iWidget *w = constAs_Widget(d);
+    const iRect bounds = bounds_Widget(w);
+    if (bounds.size.x > 0) {
+        iPaint p;
+        init_Paint(&p);
+        drawRect_Paint(&p, bounds, black_ColorId);
+        iRect tr = thumbRect_ScrollWidget_(d);
+        fillRect_Paint(&p, thumbRect_ScrollWidget_(d), gray50_ColorId);
+    }
+}
+
+iBeginDefineSubclass(ScrollWidget, Widget)
+    .processEvent = (iAny *) processEvent_ScrollWidget_,
+    .draw         = (iAny *) draw_ScrollWidget_,
+iEndDefineSubclass(ScrollWidget)