C++ (Cpp) ScrollableArea::userScroll Examples

Example #1

// Tests that scrolling the viewport when the layout viewport is
// !userInputScrollable (as happens when overflow:hidden is set) works
// correctly, that is, the visual viewport can scroll, but not the layout.
TEST_F(RootFrameViewportTest, UserInputScrollable) {
  IntSize viewportSize(100, 150);
  RootFrameViewStub* layoutViewport =
      RootFrameViewStub::create(viewportSize, IntSize(200, 300));
  VisualViewportStub* visualViewport =
      VisualViewportStub::create(viewportSize, viewportSize);

  ScrollableArea* rootFrameViewport =
      RootFrameViewport::create(*visualViewport, *layoutViewport);

  visualViewport->setScale(2);

  // Disable just the layout viewport's horizontal scrolling, the
  // RootFrameViewport should remain scrollable overall.
  layoutViewport->setUserInputScrollable(false, true);
  visualViewport->setUserInputScrollable(true, true);

  EXPECT_TRUE(rootFrameViewport->userInputScrollable(HorizontalScrollbar));
  EXPECT_TRUE(rootFrameViewport->userInputScrollable(VerticalScrollbar));

  // Layout viewport shouldn't scroll since it's not horizontally scrollable,
  // but visual viewport should.
  rootFrameViewport->userScroll(ScrollByPixel, FloatSize(300, 0));
  EXPECT_SIZE_EQ(ScrollOffset(0, 0), layoutViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(50, 0), visualViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(50, 0), rootFrameViewport->getScrollOffset());

  // Vertical scrolling should be unaffected.
  rootFrameViewport->userScroll(ScrollByPixel, FloatSize(0, 300));
  EXPECT_SIZE_EQ(ScrollOffset(0, 150), layoutViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(50, 75), visualViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(50, 225), rootFrameViewport->getScrollOffset());

  // Try the same checks as above but for the vertical direction.
  // ===============================================

  rootFrameViewport->setScrollOffset(ScrollOffset(), ProgrammaticScroll);

  // Disable just the layout viewport's vertical scrolling, the
  // RootFrameViewport should remain scrollable overall.
  layoutViewport->setUserInputScrollable(true, false);
  visualViewport->setUserInputScrollable(true, true);

  EXPECT_TRUE(rootFrameViewport->userInputScrollable(HorizontalScrollbar));
  EXPECT_TRUE(rootFrameViewport->userInputScrollable(VerticalScrollbar));

  // Layout viewport shouldn't scroll since it's not vertically scrollable,
  // but visual viewport should.
  rootFrameViewport->userScroll(ScrollByPixel, FloatSize(0, 300));
  EXPECT_SIZE_EQ(ScrollOffset(0, 0), layoutViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(0, 75), visualViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(0, 75), rootFrameViewport->getScrollOffset());

  // Horizontal scrolling should be unaffected.
  rootFrameViewport->userScroll(ScrollByPixel, FloatSize(300, 0));
  EXPECT_SIZE_EQ(ScrollOffset(100, 0), layoutViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(50, 75), visualViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(150, 75), rootFrameViewport->getScrollOffset());
}

Example #2

// Make sure scrolls using the scroll animator (scroll(), setScrollOffset())
// work correctly when one of the subviewports is explicitly scrolled without
// using the // RootFrameViewport interface.
TEST_F(RootFrameViewportTest, TestScrollAnimatorUpdatedBeforeScroll) {
  IntSize viewportSize(100, 150);
  RootFrameViewStub* layoutViewport =
      RootFrameViewStub::create(viewportSize, IntSize(200, 300));
  VisualViewportStub* visualViewport =
      VisualViewportStub::create(viewportSize, viewportSize);

  ScrollableArea* rootFrameViewport =
      RootFrameViewport::create(*visualViewport, *layoutViewport);

  visualViewport->setScale(2);

  visualViewport->setScrollOffset(ScrollOffset(50, 75), ProgrammaticScroll);
  EXPECT_SIZE_EQ(ScrollOffset(50, 75), rootFrameViewport->getScrollOffset());

  // If the scroll animator doesn't update, it will still think it's at (0, 0)
  // and so it may early exit.
  rootFrameViewport->setScrollOffset(ScrollOffset(0, 0), ProgrammaticScroll);
  EXPECT_SIZE_EQ(ScrollOffset(0, 0), rootFrameViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(0, 0), visualViewport->getScrollOffset());

  // Try again for userScroll()
  visualViewport->setScrollOffset(ScrollOffset(50, 75), ProgrammaticScroll);
  EXPECT_SIZE_EQ(ScrollOffset(50, 75), rootFrameViewport->getScrollOffset());

  rootFrameViewport->userScroll(ScrollByPixel, FloatSize(-50, 0));
  EXPECT_SIZE_EQ(ScrollOffset(0, 75), rootFrameViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(0, 75), visualViewport->getScrollOffset());

  // Make sure the layout viewport is also accounted for.
  rootFrameViewport->setScrollOffset(ScrollOffset(0, 0), ProgrammaticScroll);
  layoutViewport->setScrollOffset(ScrollOffset(100, 150), ProgrammaticScroll);
  EXPECT_SIZE_EQ(ScrollOffset(100, 150), rootFrameViewport->getScrollOffset());

  rootFrameViewport->userScroll(ScrollByPixel, FloatSize(-100, 0));
  EXPECT_SIZE_EQ(ScrollOffset(0, 150), rootFrameViewport->getScrollOffset());
  EXPECT_SIZE_EQ(ScrollOffset(0, 150), layoutViewport->getScrollOffset());
}