Implement Container widget

Remove `align_self` and `justify_content` methods

native/src/layout/flex.rs

@@ -17,7 +17,7 @@
 // limitations under the License.
 use crate::{
     layout::{Limits, Node},
-    Element, Size,
+    Align, Element, Size,
 };
 
 #[derive(Debug)]
@@ -56,6 +56,7 @@ pub fn resolve<Message, Renderer>(
     limits: &Limits,
     padding: f32,
     spacing: f32,
+    align_items: Align,
     children: &[Element<'_, Message, Renderer>],
 ) -> Node
 where
@@ -66,6 +67,7 @@ where
     let mut total_non_fill =
         spacing as f32 * (children.len() as i32 - 1).max(0) as f32;
     let mut fill_sum = 0;
+    let mut cross = axis.cross(limits.min());
 
     let mut nodes: Vec<Node> = Vec::with_capacity(children.len());
     nodes.resize(children.len(), Node::default());
@@ -81,8 +83,10 @@ where
             let child_limits = Limits::new(Size::ZERO, limits.max());
 
             let layout = child.layout(renderer, &child_limits);
+            let size = layout.size();
 
-            total_non_fill += axis.main(layout.size());
+            total_non_fill += axis.main(size);
+            cross = cross.max(axis.cross(size));
 
             nodes[i] = layout;
         } else {
@@ -120,13 +124,13 @@ where
             );
 
             let layout = child.layout(renderer, &child_limits);
+            cross = cross.max(axis.cross(layout.size()));
 
             nodes[i] = layout;
         }
     }
 
     let mut main = padding;
-    let mut cross = axis.cross(limits.min());
 
     for (i, node) in nodes.iter_mut().enumerate() {
         if i > 0 {
@@ -138,10 +142,18 @@ where
         node.bounds.x = x;
         node.bounds.y = y;
 
+        match axis {
+            Axis::Horizontal => {
+                node.align(Align::Start, align_items, Size::new(0.0, cross));
+            }
+            Axis::Vertical => {
+                node.align(align_items, Align::Start, Size::new(cross, 0.0));
+            }
+        }
+
         let size = node.size();
 
         main += axis.main(size);
-        cross = cross.max(axis.cross(size));
     }
 
     let (width, height) = axis.pack(main, cross);

native/src/layout/limits.rs

@@ -22,6 +22,14 @@ impl Limits {
         }
     }
 
+    pub fn min(&self) -> Size {
+        self.min
+    }
+
+    pub fn max(&self) -> Size {
+        self.max
+    }
+
     pub fn width(mut self, width: Length) -> Limits {
         match width {
             Length::Shrink => {
@@ -85,27 +93,6 @@ impl Limits {
         self
     }
 
-    pub fn resolve(&self, intrinsic_size: Size) -> Size {
-        Size::new(
-            intrinsic_size
-                .width
-                .min(self.max.width)
-                .max(self.fill.width),
-            intrinsic_size
-                .height
-                .min(self.max.height)
-                .max(self.fill.height),
-        )
-    }
-
-    pub fn min(&self) -> Size {
-        self.min
-    }
-
-    pub fn max(&self) -> Size {
-        self.max
-    }
-
     pub fn pad(&self, padding: f32) -> Limits {
         self.shrink(Size::new(padding * 2.0, padding * 2.0))
     }
@@ -128,4 +115,25 @@ impl Limits {
 
         Limits { min, max, fill }
     }
+
+    pub fn loose(&self) -> Limits {
+        Limits {
+            min: Size::ZERO,
+            max: self.max,
+            fill: self.fill,
+        }
+    }
+
+    pub fn resolve(&self, intrinsic_size: Size) -> Size {
+        Size::new(
+            intrinsic_size
+                .width
+                .min(self.max.width)
+                .max(self.fill.width),
+            intrinsic_size
+                .height
+                .min(self.max.height)
+                .max(self.fill.height),
+        )
+    }
 }

native/src/layout/node.rs

@@ -1,4 +1,4 @@
-use crate::{Rectangle, Size};
+use crate::{Align, Rectangle, Size};
 
 #[derive(Debug, Clone, Default)]
 pub struct Node {
@@ -34,4 +34,27 @@ impl Node {
     pub fn children(&self) -> &[Node] {
         &self.children
     }
+
+    pub fn align(
+        &mut self,
+        horizontal_alignment: Align,
+        vertical_alignment: Align,
+        space: Size,
+    ) {
+        match horizontal_alignment {
+            Align::Start => {}
+            Align::Center => {
+                self.bounds.x += (space.width - self.bounds.width) / 2.0;
+            }
+            Align::End => {}
+        }
+
+        match vertical_alignment {
+            Align::Start => {}
+            Align::Center => {
+                self.bounds.y += (space.height - self.bounds.height) / 2.0;
+            }
+            Align::End => {}
+        }
+    }
 }