Allow the initial BoxConstraints to not fill the entire screen.

Also fix issue with INIT_FLAGS

src/app.rs

@@ -309,7 +309,7 @@ impl<T: Send + 'static, V: View<T> + 'static> App<T, V> {
                 widget_state: &mut self.root_state,
                 cx_state,
             };
-            let bc = BoxConstraints::tight(self.size);
+            let bc = BoxConstraints::tight(self.size).loosen();
             root_pod.layout(&mut layout_cx, &bc);
             root_pod.set_origin(&mut layout_cx, Point::ORIGIN);
         }

src/view/snapshots/trui__view__border__tests__simple_border_test.snap

@@ -5,11 +5,11 @@ expression: buffer
 Buffer {
     area: Rect { x: 0, y: 0, width: 15, height: 5 },
     content: [
-        "┌─────────────┐",
-        "│some text    │",
-        "│             │",
-        "│             │",
-        "└─────────────┘",
+        "┌─────────┐    ",
+        "│some text│    ",
+        "└─────────┘    ",
+        "               ",
+        "               ",
     ],
     styles: [
         x: 0, y: 0, fg: Reset, bg: Reset, underline: Reset, modifier: NONE,

src/view/snapshots/trui__view__border__tests__too_small_viewport.snap

@@ -7,9 +7,9 @@ Buffer {
     content: [
         "┌─────┐",
         "│some │",
-        "│     │",
-        "│     │",
         "└─────┘",
+        "       ",
+        "       ",
     ],
     styles: [
         x: 0, y: 0, fg: Reset, bg: Reset, underline: Reset, modifier: NONE,

src/widget/box_constraints.rs

@@ -105,6 +105,20 @@ impl BoxConstraints {
         )
     }
 
+    pub fn tighten_max_height(&self) -> Self {
+        BoxConstraints::new(
+            Size::new(self.min().width, self.max().height),
+            Size::new(self.max().width, self.max().height),
+        )
+    }
+
+    pub fn tighten_max_width(&self) -> Self {
+        BoxConstraints::new(
+            Size::new(self.max().width, self.min().height),
+            Size::new(self.max().width, self.max().height),
+        )
+    }
+
     /// Create a "loose" version of the constraints.
     ///
     /// Make a version with zero minimum size, but the same maximum size.

src/widget/core.rs

@@ -215,7 +215,8 @@ bitflags! {
         const INIT_FLAGS = Self::REQUEST_UPDATE.bits()
             | Self::REQUEST_LAYOUT.bits()
             | Self::REQUEST_PAINT.bits()
-            | Self::TREE_CHANGED.bits();
+            | Self::TREE_CHANGED.bits()
+            | Self::VIEW_CONTEXT_CHANGED.bits();
     }
 }
 

src/widget/fill_max_size.rs

@@ -48,10 +48,14 @@ impl Widget for FillMaxSize {
     fn layout(&mut self, cx: &mut LayoutCx, bc: &BoxConstraints) -> Size {
         let mut bc = *bc;
         if self.fill.contains(Fill::WIDTH) && bc.is_width_bounded() {
-            bc = bc.constrain_width_to(bc.max().width * self.percent);
+            bc = bc
+                .constrain_width_to(bc.max().width * self.percent)
+                .tighten_max_width();
         }
         if self.fill.contains(Fill::HEIGHT) && bc.is_height_bounded() {
-            bc = bc.constrain_height_to(bc.max().height * self.percent);
+            bc = bc
+                .constrain_height_to(bc.max().height * self.percent)
+                .tighten_max_height();
         }
         self.content.layout(cx, &bc)
     }