WListPanel: Split margin into insets and gaps

Resolves #221.

1 files changed, 64 insertions, 5 deletions

diff --git a/src/main/java/io/github/cottonmc/cotton/gui/widget/WListPanel.java b/src/main/java/io/github/cottonmc/cotton/gui/widget/WListPanel.java
index d36fb70..5a4c35b 100644
--- a/src/main/java/io/github/cottonmc/cotton/gui/widget/WListPanel.java
+++ b/src/main/java/io/github/cottonmc/cotton/gui/widget/WListPanel.java
@@ -7,10 +7,13 @@ import net.minecraft.client.gui.DrawContext;
 import io.github.cottonmc.cotton.gui.GuiDescription;
 import io.github.cottonmc.cotton.gui.widget.data.Axis;
 import io.github.cottonmc.cotton.gui.widget.data.InputResult;
+import io.github.cottonmc.cotton.gui.widget.data.Insets;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Objects;
 import java.util.function.BiConsumer;
 import java.util.function.Supplier;
 
@@ -51,8 +54,16 @@ public class WListPanel<D, W extends WWidget> extends WClippedPanel {
 	 */
 	protected boolean fixedHeight = false;
 
+	/**
+	 * @deprecated Replaced with {@link #getInsets() insets} and {@link #getGap() gap}.
+	 */
+	@Deprecated(forRemoval = true)
 	protected int margin = 4;
 
+	// When the margin field is removed, these should get default values Insets(4, 4) and 4.
+	private @Nullable Insets insets = null;
+	private int gap = -1;
+
 	/**
 	 * The scroll bar of this list.
 	 */
@@ -153,8 +164,10 @@ public class WListPanel<D, W extends WWidget> extends WClippedPanel {
 		}
 		if (cellHeight<4) cellHeight=4;
 
-		int layoutHeight = this.getHeight()-(margin*2);
-		int cellsHigh = Math.max((layoutHeight+margin) / (cellHeight + margin), 1); // At least one cell is always visible
+		Insets insets = getInsets();
+		int gap = getGap();
+		int layoutHeight = this.getHeight() - insets.top() - insets.bottom();
+		int cellsHigh = Math.max((layoutHeight + gap) / (cellHeight + gap), 1); // At least one cell is always visible
 
 		//System.out.println("Adding children...");
 
@@ -190,10 +203,10 @@ public class WListPanel<D, W extends WWidget> extends WClippedPanel {
 
 				//At this point, w is nonnull and configured by d
 				if (w.canResize()) {
-					w.setSize(this.width-(margin*2) - scrollBar.getWidth(), cellHeight);
+					w.setSize(this.width - insets.left() - insets.right() - scrollBar.getWidth(), cellHeight);
 				}
-				w.x = margin;
-				w.y = margin + ((cellHeight+margin) * i);
+				w.x = insets.left();
+				w.y = insets.top() + ((cellHeight + gap) * i);
 				this.children.add(w);
 			}
 		}
@@ -227,4 +240,50 @@ public class WListPanel<D, W extends WWidget> extends WClippedPanel {
 	public WScrollBar getScrollBar() {
 		return scrollBar;
 	}
+
+	/**
+	 * {@return the layout insets used for the contents of this list}
+	 * @since 9.1.0
+	 */
+	public Insets getInsets() {
+		// Returns the *effective* insets of this list for backwards compat.
+		return insets != null ? insets : new Insets(margin, margin);
+	}
+
+	/**
+	 * Sets the layout insets used for the contents of this list.
+	 *
+	 * @param insets the layout insets
+	 * @return this list
+	 * @since 9.1.0
+     */
+	public WListPanel<D, W> setInsets(Insets insets) {
+		this.insets = Objects.requireNonNull(insets, "Insets cannot be null");
+		return this;
+	}
+
+	/**
+	 * {@return the gap between list items}
+	 * @since 9.1.0
+	 */
+	public int getGap() {
+		// Returns the *effective* gap of this list for backwards compat.
+		return gap >= 0 ? gap : margin;
+	}
+
+	/**
+	 * Sets the gap between list items.
+	 *
+	 * @param gap the gap, must be non-negative
+	 * @return this list
+	 * @since 9.1.0
+	 */
+	public WListPanel<D, W> setGap(int gap) {
+		if (gap < 0) {
+			throw new IllegalArgumentException("Gap cannot be negative (was " + gap + ")");
+		}
+
+		this.gap = gap;
+		return this;
+	}
 }