moved mouse drag distance threshold into Theme so that it can be specified by the application

Author: psFried

src/events/global_input.rs

@@ -38,10 +38,10 @@ impl <'a> InputProvider<'a, GlobalInputEventIterator<'a>> for GlobalInput {
 impl GlobalInput {
 
     /// Returns a fresh new `GlobalInput`
-    pub fn new() -> GlobalInput {
+    pub fn new(drag_threshold: Scalar) -> GlobalInput {
         GlobalInput{
             events: Vec::new(),
-            drag_threshold: 4.0,
+            drag_threshold: drag_threshold,
             start_state: InputState::new(),
             current_state: InputState::new(),
         }

src/tests/global_input.rs

@@ -9,7 +9,7 @@ use widget::{Id, Index};
 
 #[test]
 fn resetting_input_should_set_starting_state_to_current_state() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
     input.push_event(UiEvent::Raw(Input::Press(Keyboard(Key::LShift))));
     input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(0.0, 50.0))));
 
@@ -20,7 +20,7 @@ fn resetting_input_should_set_starting_state_to_current_state() {
 
 #[test]
 fn resetting_input_should_clear_out_all_events() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
     input.push_event(UiEvent::Raw(Input::Press(Keyboard(Key::LShift))));
     input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(0.0, 50.0))));
     input.reset();
@@ -29,7 +29,7 @@ fn resetting_input_should_clear_out_all_events() {
 
 #[test]
 fn scroll_events_should_have_modifier_keys() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     input.push_event(UiEvent::Raw(Input::Press(Keyboard(Key::LShift))));
     input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(0.0, 50.0))));
@@ -40,7 +40,7 @@ fn scroll_events_should_have_modifier_keys() {
 
 #[test]
 fn global_input_should_track_widget_currently_capturing_keyboard() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     let idx: Index = Index::Public(Id(5));
     input.push_event(UiEvent::WidgetCapturesKeyboard(idx));
@@ -57,7 +57,7 @@ fn global_input_should_track_widget_currently_capturing_keyboard() {
 
 #[test]
 fn global_input_should_track_widget_currently_capturing_mouse() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     let idx: Index = Index::Public(Id(5));
     input.push_event(UiEvent::WidgetCapturesMouse(idx));
@@ -74,15 +74,15 @@ fn global_input_should_track_widget_currently_capturing_mouse() {
 
 #[test]
 fn global_input_should_track_current_mouse_position() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     input.push_event(mouse_move_event(50.0, 77.7));
     assert_eq!([50.0, 77.7], input.mouse_position());
 }
 
 #[test]
 fn entered_text_should_be_aggregated_from_multiple_events() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     input.push_event(UiEvent::Raw(Input::Text("Phil ".to_string())));
     input.push_event(UiEvent::Raw(Input::Text("is a".to_string())));
@@ -94,7 +94,7 @@ fn entered_text_should_be_aggregated_from_multiple_events() {
 
 #[test]
 fn drag_event_should_still_be_created_if_reset_is_called_between_press_and_release() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
 
     input.push_event(UiEvent::Raw(Input::Press(Mouse(MouseButton::Left))));
     input.push_event(mouse_move_event(50.0, 77.7));
@@ -106,7 +106,7 @@ fn drag_event_should_still_be_created_if_reset_is_called_between_press_and_relea
 
 #[test]
 fn click_event_should_still_be_created_if_reset_is_called_between_press_and_release() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
 
     input.push_event(UiEvent::Raw(Input::Press(Mouse(MouseButton::Left))));
     input.reset();
@@ -117,7 +117,7 @@ fn click_event_should_still_be_created_if_reset_is_called_between_press_and_rele
 
 #[test]
 fn no_events_should_be_returned_after_reset_is_called() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
     input.push_event(UiEvent::Raw(Input::Press(Keyboard(Key::RShift))));
     input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(7.0, 88.5))));
     input.push_event(UiEvent::Raw(Input::Press(Mouse(MouseButton::Left))));
@@ -133,7 +133,7 @@ fn no_events_should_be_returned_after_reset_is_called() {
 fn drag_with_modifer_key_should_include_modifiers_in_drag_event() {
     use input::keyboard::SHIFT;
 
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
     input.push_event(UiEvent::Raw(Input::Press(Keyboard(Key::RShift))));
     input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(7.0, 88.5))));
 
@@ -146,7 +146,7 @@ fn drag_with_modifer_key_should_include_modifiers_in_drag_event() {
 fn click_with_modifier_key_should_include_modifiers_in_click_event() {
     use input::keyboard::CTRL;
 
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
     input.push_event(UiEvent::Raw(Input::Press(Keyboard(Key::LCtrl))));
     input.push_event(UiEvent::Raw(Input::Press(Mouse(MouseButton::Left))));
     input.push_event(UiEvent::Raw(Input::Release(Mouse(MouseButton::Left))));
@@ -162,7 +162,7 @@ fn click_with_modifier_key_should_include_modifiers_in_click_event() {
 
 #[test]
 fn high_level_scroll_event_should_be_created_from_a_raw_mouse_scroll() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(10.0, 33.0))));
 
@@ -177,7 +177,7 @@ fn high_level_scroll_event_should_be_created_from_a_raw_mouse_scroll() {
 
 #[test]
 fn mouse_button_pressed_moved_released_creates_final_drag_event() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
 
     input.push_event(UiEvent::Raw(Input::Press(Mouse(MouseButton::Left))));
     input.push_event(mouse_move_event(20.0, 10.0));
@@ -196,7 +196,7 @@ fn mouse_button_pressed_moved_released_creates_final_drag_event() {
 
 #[test]
 fn mouse_button_pressed_then_moved_creates_drag_event() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
 
     let press = UiEvent::Raw(Input::Press(Mouse(MouseButton::Left)));
     let mouse_move = mouse_move_event(20.0, 10.0);
@@ -216,7 +216,7 @@ fn mouse_button_pressed_then_moved_creates_drag_event() {
 
 #[test]
 fn mouse_click_position_should_be_mouse_position_when_pressed() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
 
     input.push_event(mouse_move_event(4.0, 5.0));
     input.push_event(UiEvent::Raw(Input::Press(Mouse(MouseButton::Left))));
@@ -236,7 +236,7 @@ fn mouse_click_position_should_be_mouse_position_when_pressed() {
 
 #[test]
 fn mouse_button_pressed_then_released_should_create_mouse_click_event() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(4.0);
 
     let press = UiEvent::Raw(Input::Press(Mouse(MouseButton::Left)));
     let release = UiEvent::Raw(Input::Release(Mouse(MouseButton::Left)));
@@ -255,7 +255,7 @@ fn mouse_button_pressed_then_released_should_create_mouse_click_event() {
 
 #[test]
 fn all_events_should_return_all_inputs_in_order() {
-    let mut input = GlobalInput::new();
+    let mut input = GlobalInput::new(0.0);
 
     let evt1 = UiEvent::Raw(Input::Press(Keyboard(Key::Z)));
     input.push_event(evt1.clone());

src/tests/widget_input.rs

@@ -8,7 +8,7 @@ use position::Rect;
 #[test]
 fn maybe_mouse_position_should_return_position_if_mouse_is_over_the_widget() {
     let widget_area = Rect::from_corners([10.0, 10.0], [50.0, 50.0]);
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseRelative(30.0, 30.0))));
 
     let widget_input = WidgetInput::for_widget(Index::Public(Id(2)), widget_area, &global_input);
@@ -20,7 +20,7 @@ fn maybe_mouse_position_should_return_position_if_mouse_is_over_the_widget() {
 #[test]
 fn maybe_mouse_position_should_return_none_if_mouse_is_not_over_the_widget() {
     let widget_area = Rect::from_corners([10.0, 10.0], [50.0, 50.0]);
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseRelative(-10.0, -10.0))));
 
     let widget_input = WidgetInput::for_widget(Index::Public(Id(2)), widget_area, &global_input);
@@ -32,7 +32,7 @@ fn maybe_mouse_position_should_return_none_if_mouse_is_not_over_the_widget() {
 #[test]
 fn mouse_is_over_widget_should_be_true_if_mouse_is_over_the_widget_area() {
     let widget_area = Rect::from_corners([10.0, 10.0], [50.0, 50.0]);
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseRelative(30.0, 30.0))));
 
     let widget_input = WidgetInput::for_widget(Index::Public(Id(2)), widget_area, &global_input);
@@ -43,7 +43,7 @@ fn mouse_is_over_widget_should_be_true_if_mouse_is_over_the_widget_area() {
 #[test]
 fn mouse_is_over_widget_should_be_false_if_mouse_is_not_over_widget() {
     let widget_area = Rect::from_corners([10.0, 10.0], [50.0, 50.0]);
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseRelative(90.0, 90.0))));
 
     let widget_input = WidgetInput::for_widget(Index::Public(Id(2)), widget_area, &global_input);
@@ -54,7 +54,7 @@ fn mouse_is_over_widget_should_be_false_if_mouse_is_not_over_widget() {
 #[test]
 fn input_state_should_be_provided_relative_to_the_widget_area() {
     let widget_area = Rect::from_corners([10.0, 10.0], [50.0, 50.0]);
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseRelative(30.0, 30.0))));
 
     let widget_input = WidgetInput::for_widget(Index::Public(Id(2)), widget_area, &global_input);
@@ -64,7 +64,7 @@ fn input_state_should_be_provided_relative_to_the_widget_area() {
 
 #[test]
 fn scroll_events_should_be_provided_if_widget_captures_mouse_but_not_keyboard() {
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     let widget = Index::Public(Id(1));
     global_input.push_event(UiEvent::WidgetCapturesMouse(widget));
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(0.0, -76.0))));
@@ -76,7 +76,7 @@ fn scroll_events_should_be_provided_if_widget_captures_mouse_but_not_keyboard()
 
 #[test]
 fn scroll_events_should_be_provided_if_widget_captures_keyboard_but_not_mouse() {
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     let widget = Index::Public(Id(1));
     global_input.push_event(UiEvent::WidgetCapturesKeyboard(widget));
     global_input.push_event(UiEvent::Raw(Input::Move(Motion::MouseScroll(0.0, -76.0))));
@@ -88,7 +88,7 @@ fn scroll_events_should_be_provided_if_widget_captures_keyboard_but_not_mouse()
 
 #[test]
 fn widget_input_should_provide_any_mouse_events_over_the_widgets_area_if_nothing_is_capturing_mouse() {
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::MouseClick(MouseClick{
         button: MouseButton::Left,
         location: [10.0, 10.0],
@@ -111,7 +111,7 @@ fn widget_input_should_provide_any_mouse_events_over_the_widgets_area_if_nothing
 
 #[test]
 fn widget_input_should_only_provide_keyboard_input_to_widget_that_has_focus() {
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
 
     let some_rect = Rect::from_corners([0.0, 0.0], [40.0, 40.0]);
     let widget_4 = Index::Public(Id(4));
@@ -131,7 +131,7 @@ fn widget_input_should_only_provide_keyboard_input_to_widget_that_has_focus() {
 #[test]
 fn mouse_clicks_should_be_relative_to_widget_position() {
     let idx = Index::Public(Id(5));
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::MouseClick(MouseClick{
         button: MouseButton::Left,
         location: [10.0, 10.0],
@@ -149,7 +149,7 @@ fn mouse_drags_should_be_relative_to_widget_position() {
     use events::MouseDrag;
 
     let idx = Index::Public(Id(5));
-    let mut global_input = GlobalInput::new();
+    let mut global_input = GlobalInput::new(4.0);
     global_input.push_event(UiEvent::MouseDrag(MouseDrag{
         button: MouseButton::Left,
         start: [5.0, 5.0],

src/theme.rs

@@ -40,6 +40,9 @@ pub struct Theme {
     pub maybe_scrollbar: Option<widget::scroll::Style>,
     /// Unique styling for each widget, index-able by the **Widget::kind**.
     pub widget_styling: HashMap<&'static str, WidgetDefault>,
+    /// Mouse Drag distance threshold determines the minimum distance from the mouse-down point
+    /// that the mouse must move before starting a drag operation.
+    pub mouse_drag_threshold: Scalar,
 }
 
 /// The defaults for a specific widget.
@@ -69,6 +72,8 @@ impl WidgetDefault {
     }
 }
 
+/// This is the default value that is used for `Theme::mouse_drag_threshold`.
+pub const DEFAULT_MOUSE_DRAG_THRESHOLD: Scalar = 4.0;
 
 impl Theme {
 
@@ -89,6 +94,7 @@ impl Theme {
             font_size_small: 12,
             maybe_scrollbar: None,
             widget_styling: HashMap::new(),
+            mouse_drag_threshold: DEFAULT_MOUSE_DRAG_THRESHOLD,
         }
     }
 
@@ -110,4 +116,3 @@ impl Theme {
     }
 
 }
-

src/ui.rs

@@ -148,6 +148,7 @@ impl<C> Ui<C> {
     {
         let window = widget_graph.add_placeholder();
         let prev_updated_widgets = updated_widgets.clone();
+        let mouse_drag_threshold = theme.mouse_drag_threshold;
         Ui {
             widget_graph: widget_graph,
             theme: theme,
@@ -171,7 +172,7 @@ impl<C> Ui<C> {
             depth_order: depth_order,
             updated_widgets: updated_widgets,
             prev_updated_widgets: prev_updated_widgets,
-            global_input: GlobalInput::new(),
+            global_input: GlobalInput::new(mouse_drag_threshold),
         }
     }