2.4 Nest of layouts ¶
To wrap up our discussion on using the LayoutMorph class, let’s look at an example that nests layouts
column1 := LayoutMorph newColumn
addMorph: (LabelMorph contents: 'Apple');
addMorph: (LabelMorph contents: 'Banana');
addMorph: (LabelMorph contents: 'Cherry').
column1 layoutSpec proportionalHeight: 0. "defaults to 1"
column2 := LayoutMorph newColumn
addMorph: (LabelMorph contents: 'Spring');
addMorph: (LabelMorph contents: 'Winter');
addMorph: (LabelMorph contents: 'Summer');
addMorph: (LabelMorph contents: 'Fall').
column2 layoutSpec proportionalHeight: 0. "defaults to 1"
row := LayoutMorph newRow
separation: 20;
addMorph: column1;
addMorph: (LabelMorph contents: 'What are your favorites?');
addMorph: column2.
row openInWorld.
Example 2.3: Nesting layouts
Figure 2.10: Nested LayoutMorphs
We can add a colored border to any morph that is an instance of a subclass of BorderedBoxMorph. This is useful for debugging.
Let’s add borders to some of the morphs in the previous example Example 2.3
column1 := LayoutMorph newColumn
addMorph: (LabelMorph contents: 'Apple');
addMorph: (LabelMorph contents: 'Banana');
addMorph: (LabelMorph contents: 'Cherry');
borderColor: Color red; borderWidth: 2.
column1 layoutSpec proportionalHeight: 0.
column2 := LayoutMorph newColumn
addMorph: (LabelMorph contents: 'Spring');
addMorph: (LabelMorph contents: 'Winter');
addMorph: (LabelMorph contents: 'Summer');
addMorph: (LabelMorph contents: 'Fall');
borderColor: Color blue; borderWidth: 2.
column2 layoutSpec proportionalHeight: 0.
center := LabelMorph contents: 'What are your favorites?' ::
borderColor: Color green; borderWidth: 2.
row := LayoutMorph newRow
separation: 20;
addMorph: column1;
addMorph: center;
addMorph: column2.
row openInWorld.
Example 2.4: Revealed nested layouts
Figure 2.11: Morph borders