added mouse event handling

README.md

@@ -15,6 +15,9 @@ extensible, allowing for complex interfaces to be built in it.
 - Supports custom elements/skins, make your own and move them into the
   appropriate directories for them to be automatically loaded.
 
+**Note**: Skins are currently a work-in-progress, and not automatically loaded.
+See the documentation linked to below.
+
 ## Usage
 
 ```lua

docs/Elements.md

@@ -29,6 +29,21 @@ All elements have the following standard methods:
 - `setAlignment(horizontal, vertical)` - Sets alignment *values* to this, but
   does not move the element. Same `horizontal`/`vertical` strings as `align()`
 
+Events:
+
+If any of these is set as a function, they will be called when the appropriate
+event happens.
+
+- `mousepressed(button, x, y)` - Called the moment a mouse click starts, uses
+  the same values for `button` as [love.mousepressed][4], but the `x`/`y` are
+  relative to the element.
+- `mousereleased(button, x, y)` - Called the moment a mouse click stops, uses
+  the same values for `button` as [love.mousepressed][4], but the `x`/`y` are
+  relative to the element.
+- `clicked(button, x, y)` - Called when a mouse click stops if it started on the
+  same element. Uses the same values for `button` as [love.mousepressed][4], but
+  the `x`/`y` are relative to the element.
+
 **Note**! Calls to `align()`, `alignTo()`, and `setAlignment()` change what
 positions will be returned, and how positioning and resizing will work. Run the
 demo to see how these affect things.
@@ -98,3 +113,4 @@ not be rendered.
 [1]: ./Skins.md
 [2]: https://love2d.org/wiki/Font
 [3]: ./Drawables.md
+[4]: https://love2d.org/wiki/love.mousepressed

docs/Pop.md

@@ -16,6 +16,8 @@ elements at once.
 
 - `pop.window` is the top level element. It essentially represents the game
   window.
+- `pop.focused` holds a reference to the last clicked on element (that handled
+  the click using `element:mousepressed()` (see [Elements.md][1])).
 - `pop.create(element, parent, ...)` is how elements are actually created,
   `element` is a string naming the desired element. There are wrappers around
   any element that doesn't conflict with a key in the `pop` module so that you
@@ -36,10 +38,10 @@ elements at once.
 - `pop.textinput(text)` is used to grab text input for any focused element that
   can accept it.
 - `pop.mousepressed(button, x, y)` is used to detect and handle when an element
-  is clicked on. (Not actually used yet.)
+  is clicked on. See [Elements.md][1].
+- `pop.mousereleased(button, x, y)` is used to detect and handle when a mouse
+  button is released over an element. See [Elements.md][1].
 
-- `pop.mousereleased(button, x, y)` is not used yet, but probably will be used
-  in the future.
 - `pop.keypressed(key)` is not used yet, but probably will be used in the
   future.
 - `pop.keyreleased(key)` is also not used yet, but probably will be used in the

pop/init.lua

@@ -6,7 +6,7 @@ local pop = {}
 pop.elementClasses = {}
 --pop.elements = {}
 pop.window = {child = {}} --top level element, defined in pop.load()
---TODO we need a "focused" element for textinput or whatever
+pop.focused = pop.window  --defaults to top level
 
 function pop.load()
     -- load element classes
@@ -72,12 +72,62 @@ function pop.draw(element)
     end
 end
 
-function pop.mousepressed(button, x, y)
+function pop.mousepressed(button, x, y, element)
-    --TODO find element, if it has a callback, call with button and LOCAL x/y
+    if not element then
+        element = pop.window
+
+        if (x < element.x) or (y < element.y) or
+        (x > (element.x + element.w)) or (y > (element.y + element.h)) then
+            return
+        end
     end
 
-function pop.mousereleased(button, x, y)
+    local handled = false
-    --TODO find element, if it has a callback, call with button and LOCAL x/y
+    for i=1,#element.child do
+        if (x >= element.x) and (y >= element.y) and
+        (x <= (element.x + element.w)) and (y <= (element.y + element.h)) then
+            handled = pop.mousepressed(button, x, y, element.child[i])
+        end
+    end
+
+    if (not handled) and element.mousepressed then
+        element:mousepressed(button, x - element.x, y - element.y)
+        pop.focused = element
+    end
+
+    return handled
+end
+
+function pop.mousereleased(button, x, y, element)
+    if not element then
+        element = pop.window
+
+        if (x < element.x) or (y < element.y) or
+        (x > (element.x + element.w)) or (y > (element.y + element.h)) then
+            return
+        end
+    end
+
+    local handled = false
+    for i=1,#element.child do
+        if (x >= element.x) and (y >= element.y) and
+        (x <= (element.x + element.w)) and (y <= (element.y + element.h)) then
+            handled = pop.mousereleased(button, x, y, element.child[i])
+        end
+    end
+
+    if not handled then
+        if element.mousereleased then
+            element:mousereleased(button, x - element.x, y - element.y)
+            handled = true
+        end
+        if element.clicked then
+            element:clicked(button, x - element.x, y - element.y)
+            handled = true
+        end
+    end
+
+    return handled
 end
 
 function pop.keypressed(key)