void UpdateEnabled(double value)
{
double increment = Increment;
if (_plus != null)
{
if (value + increment > Maximum)
{
_plusStateCache = PseudoDisable(_plus);
}
else
{
PsuedoEnable(_plus, ref _plusStateCache);
}
}
if (_minus != null)
{
if (value - increment < Minimum)
{
_minusStateCache = PseudoDisable(_minus);
}
else
{
PsuedoEnable(_minus, ref _minusStateCache);
}
}
}
/*
* The below serves as a way to disable the button visually, rather than using IsEnabled. It's a hack
* but should remain stable as long as the user doesn't change the WinRT Button template too much.
*
* The reason we're not using IsEnabled is that the buttons have a click radius that overlap about 40%
* of the next button. This doesn't cause a problem until one button becomes disabled, then if you think
* you're still hitting + (haven't noticed its disabled), you will actually hit -. This hack doesn't
* completely solve the problem, but it drops the overlap to something like 20%. I haven't found the root
* cause, so this will have to suffice for now.
*/
void PsuedoEnable(Control control, ref VisualStateCache cache)
{
if (cache == null || VisualTreeHelper.GetChildrenCount(control) == 0)
{
return;
}
var rootElement = (FrameworkElement)VisualTreeHelper.GetChild(control, 0);
IList <VisualStateGroup> groups = VisualStateManager.GetVisualStateGroups(rootElement);
if (cache.FocusStates != null)
{
groups.Add(cache.FocusStates);
}
var commonStates = groups.FirstOrDefault(g => g.Name == "CommonStates");
if (commonStates == null)
{
return;
}
if (cache.Normal != null)
{
commonStates.States.Insert(0, cache.Normal); // defensive
}
if (cache.Pressed != null)
{
commonStates.States.Add(cache.Pressed);
}
if (cache.PointerOver != null)
{
commonStates.States.Add(cache.PointerOver);
}
VisualStateManager.GoToState(control, "Normal", true);
cache = null;
}
VisualStateCache PseudoDisable(Control control)
{
if (VisualTreeHelper.GetChildrenCount(control) == 0)
{
control.ApplyTemplate();
}
VisualStateManager.GoToState(control, "Disabled", true);
var rootElement = (FrameworkElement)VisualTreeHelper.GetChild(control, 0);
var cache = new VisualStateCache();
IList <VisualStateGroup> groups = VisualStateManager.GetVisualStateGroups(rootElement);
VisualStateGroup common = null;
foreach (var group in groups)
{
if (group.Name == "CommonStates")
{
common = group;
}
else if (group.Name == "FocusStates")
{
cache.FocusStates = group;
}
else if (cache.FocusStates != null && common != null)
{
break;
}
}
if (cache.FocusStates != null)
{
groups.Remove(cache.FocusStates);
}
if (common != null)
{
foreach (VisualState state in common.States)
{
if (state.Name == "Normal")
{
cache.Normal = state;
}
else if (state.Name == "Pressed")
{
cache.Pressed = state;
}
else if (state.Name == "PointerOver")
{
cache.PointerOver = state;
}
}
if (cache.Normal != null)
{
common.States.Remove(cache.Normal);
}
if (cache.Pressed != null)
{
common.States.Remove(cache.Pressed);
}
if (cache.PointerOver != null)
{
common.States.Remove(cache.PointerOver);
}
}
return(cache);
}
void UpdateEnabled(double value)
{
double increment = Increment;
if (_plus != null)
{
if (value + increment > Maximum)
_plusStateCache = PseudoDisable(_plus);
else
PsuedoEnable(_plus, ref _plusStateCache);
}
if (_minus != null)
{
if (value - increment < Minimum)
_minusStateCache = PseudoDisable(_minus);
else
PsuedoEnable(_minus, ref _minusStateCache);
}
}
/*
The below serves as a way to disable the button visually, rather than using IsEnabled. It's a hack
but should remain stable as long as the user doesn't change the WinRT Button template too much.
The reason we're not using IsEnabled is that the buttons have a click radius that overlap about 40%
of the next button. This doesn't cause a problem until one button becomes disabled, then if you think
you're still hitting + (haven't noticed its disabled), you will actually hit -. This hack doesn't
completely solve the problem, but it drops the overlap to something like 20%. I haven't found the root
cause, so this will have to suffice for now.
*/
void PsuedoEnable(Control control, ref VisualStateCache cache)
{
if (cache == null || VisualTreeHelper.GetChildrenCount(control) == 0)
return;
var rootElement = (FrameworkElement)VisualTreeHelper.GetChild(control, 0);
IList<VisualStateGroup> groups = VisualStateManager.GetVisualStateGroups(rootElement);
if (cache.FocusStates != null)
groups.Add(cache.FocusStates);
var commonStates = groups.FirstOrDefault(g => g.Name == "CommonStates");
if (commonStates == null)
return;
if (cache.Normal != null)
commonStates.States.Insert(0, cache.Normal); // defensive
if (cache.Pressed != null)
commonStates.States.Add(cache.Pressed);
if (cache.PointerOver != null)
commonStates.States.Add(cache.PointerOver);
VisualStateManager.GoToState(control, "Normal", true);
cache = null;
}
VisualStateCache PseudoDisable(Control control)
{
if (VisualTreeHelper.GetChildrenCount(control) == 0)
control.ApplyTemplate();
VisualStateManager.GoToState(control, "Disabled", true);
var rootElement = (FrameworkElement)VisualTreeHelper.GetChild(control, 0);
var cache = new VisualStateCache();
IList<VisualStateGroup> groups = VisualStateManager.GetVisualStateGroups(rootElement);
VisualStateGroup common = null;
foreach (var group in groups)
{
if (group.Name == "CommonStates")
common = group;
else if (group.Name == "FocusStates")
cache.FocusStates = group;
else if (cache.FocusStates != null && common != null)
break;
}
if (cache.FocusStates != null)
groups.Remove(cache.FocusStates);
if (common != null)
{
foreach (VisualState state in common.States)
{
if (state.Name == "Normal")
cache.Normal = state;
else if (state.Name == "Pressed")
cache.Pressed = state;
else if (state.Name == "PointerOver")
cache.PointerOver = state;
}
if (cache.Normal != null)
common.States.Remove(cache.Normal);
if (cache.Pressed != null)
common.States.Remove(cache.Pressed);
if (cache.PointerOver != null)
common.States.Remove(cache.PointerOver);
}
return cache;
}
