app.nit: fix name of `align` parameter for use in autoinit

[nit.git] / lib / app / ui.nit

diff --git a/lib/app/ui.nit b/lib/app/ui.nit
index 4efbb87..cb45ac2 100644 (file)
--- a/lib/app/ui.nit
+++ b/lib/app/ui.nit
@@ -18,9 +18,8 @@ module ui
 import app_base
 
 # Platform variations
-# TODO: move on the platform once qualified names are understand in the condition
 import linux::ui is conditional(linux)
-import android::ui is conditional(android) # FIXME it should be conditional to `android::platform`
+import android::ui is conditional(android)
 import ios::ui is conditional(ios)
 
 redef class App
@@ -28,8 +27,32 @@ redef class App
 
        # The current `Window` of this activity
        #
-       # This attribute must be set by refinements of `App`.
-       var window: Window is writable
+       # This attribute is set by `push_window`.
+       var window: Window is noinit
+
+       # Make visible and push `window` on the top of `pop_window`
+       #
+       # This method must be called at least once within `App::on_create`.
+       # It can be called at any times while the app is active.
+       fun push_window(window: Window)
+       do
+               window_stack.add window
+               self.window = window
+       end
+
+       # Pop the current `window` from the stack and show the previous one
+       #
+       # Require: `window_stack.not_empty`
+       fun pop_window
+       do
+               assert window_stack.not_empty
+               window_stack.pop
+               window = window_stack.last
+               window.on_resume
+       end
+
+       # Stack of active windows
+       var window_stack = new Array[Window]
 
        redef fun on_create do window.on_create
 
@@ -141,6 +164,12 @@ end
 # A window, root of the `Control` tree
 class Window
        super CompositeControl
+
+       # Should the back button be shown and used to go back to a previous window?
+       fun enable_back_button: Bool do return app.window_stack.length > 1
+
+       # The back button has been pressed, usually to open the previous window
+       fun on_back_button do app.pop_window
 end
 
 # A viewable `Control`
@@ -182,7 +211,7 @@ abstract class TextView
        # depending on the customization options of each platform.
        # For consistent results, it is recommended to use only on instances
        # of `Label` and `size` should be either 0.0, 0.5 or 1.0.
-       fun align=(center: nullable Float) is autoinit do end
+       fun align=(align: nullable Float) is autoinit do end
 end
 
 # A control for the user to enter custom `text`
@@ -211,12 +240,29 @@ class CheckBox
        var is_checked = false is writable
 end
 
+# Event sent from a `VIEW`
+class ViewEvent
+       super AppEvent
+
+       # The `VIEW` that raised this event
+       var sender: VIEW
+
+       # Type of the `sender`
+       type VIEW: View
+end
+
 # A `Button` press event
 class ButtonPressEvent
-       super AppEvent
+       super ViewEvent
+
+       redef type VIEW: Button
+end
+
+# The `CheckBox` `sender` has been toggled
+class ToggleEvent
+       super ViewEvent
 
-       # The `Button` that raised this event
-       var sender: Button
+       redef type VIEW: CheckBox
 end
 
 # A layout to visually organize `Control`s