Allow scrollbars to hide instead of disable

Affects: #14 Affects: #13
io7m-com · Nov 26, 2023 · 5f3a18d · 5f3a18d
1 parent 9017bd0
commit 5f3a18d
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Showing 13 changed files with 170 additions and 198 deletions.
diff --git a/com.io7m.jsycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyComponentType.java b/com.io7m.jsycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyComponentType.java
@@ -80,7 +80,7 @@ default PAreaSizeI<SySpaceParentRelativeType> layout(
     Objects.requireNonNull(constraints, "constraints");
 
     /*
-     * First, consult the theme to see if there are size constraints specified
+     * Consult the theme to see if there are size constraints specified
      * for this component. Derive a new set of constraints that try to
      * satisfy the theme whilst also satisfying the passed in constraints.
      */

diff --git a/com.io7m.jsycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyConstraints.java b/com.io7m.jsycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyConstraints.java
@@ -37,6 +37,9 @@ public record SyConstraints(
   int sizeMaximumX,
   int sizeMaximumY)
 {
+  private static final SyConstraints ZERO =
+    new SyConstraints(0, 0, 0, 0);
+
   /**
    * A set of size constraints.
    *
@@ -62,6 +65,15 @@ public SyConstraints(
       Math.clamp(sizeMaximumY, this.sizeMinimumY, MAX_VALUE);
   }
 
+  /**
+   * @return Constraints that force a zero size
+   */
+
+  public static SyConstraints zero()
+  {
+    return ZERO;
+  }
+
   /**
    * @param <T> The coordinate space type
    *

diff --git a/...components/SyScrollBarPresencePolicy.java → ...components/SyScrollBarHideIfDisabled.java b/...components/SyScrollBarPresencePolicy.java → ...components/SyScrollBarHideIfDisabled.java
@@ -18,22 +18,22 @@
 package com.io7m.jsycamore.api.components;
 
 /**
- * The presence policy for scrollbars.
+ * A specification of whether to collapse scrollbars to zero size when
+ * disabled.
  */
 
-public enum SyScrollBarPresencePolicy
+public enum SyScrollBarHideIfDisabled
 {
   /**
-   * The scrollbar should always be present and enabled.
+   * When disabled, the scrollbar collapses to zero size and is effectively
+   * hidden.
    */
 
-  ALWAYS_ENABLED,
+  HIDE_IF_DISABLED,
 
   /**
-   * The scrollbar is disabled if the entire range is shown.
-   *
-   * @see SyScrollBarType#setScrollAmountShown(double)
+   * When disabled, the scrollbar remains visible.
    */
 
-  DISABLED_IF_ENTIRE_RANGE_SHOWN
+  SHOW_EVEN_IF_DISABLED
 }
diff --git a/...sycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyScrollBarReadableType.java b/...sycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyScrollBarReadableType.java
@@ -37,6 +37,12 @@ public interface SyScrollBarReadableType
 
   SyComponentReadableType track();
 
+  /**
+   * @return The scroll amount shown in the range {@code [0, 1]}
+   */
+
+  double scrollAmountShown();
+
   /**
    * @return The scroll position in the range {@code [0, 1]}
    */
@@ -59,10 +65,4 @@ public interface SyScrollBarReadableType
    */
 
   double scrollIncrementSize();
-
-  /**
-   * @return The scrollbar presence policy
-   */
-
-  AttributeReadableType<SyScrollBarPresencePolicy> presencePolicy();
 }
diff --git a/com.io7m.jsycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyScrollBarType.java b/com.io7m.jsycamore.api/src/main/java/com/io7m/jsycamore/api/components/SyScrollBarType.java
@@ -16,7 +16,7 @@
 
 package com.io7m.jsycamore.api.components;
 
-import com.io7m.jattribute.core.AttributeType;
+import com.io7m.jsycamore.api.layout.SyLayoutContextType;
 
 import java.util.function.Consumer;
 
@@ -27,8 +27,17 @@
 public interface SyScrollBarType
   extends SyScrollBarReadableType, SyComponentType
 {
-  @Override
-  AttributeType<SyScrollBarPresencePolicy> presencePolicy();
+  /**
+   * Allow for hiding the scrollbar if it is disabled. If hiding-if-disabled
+   * is enabled, then the scrollbar's size will collapse to zero when
+   * {@link #layout(SyLayoutContextType, SyConstraints)} is called and the
+   * scrollbar is disabled.
+   *
+   * @param hideIfDisabled The hide-if-disabled setting
+   */
+
+  void setHideIfDisabled(
+    SyScrollBarHideIfDisabled hideIfDisabled);
 
   /**
    * Set the scroll position in the range {@code [0, 1]}.

diff --git a/...rc/main/java/com/io7m/jsycamore/components/standard/internal/scrollbars/SyScrollBarH.java b/...rc/main/java/com/io7m/jsycamore/components/standard/internal/scrollbars/SyScrollBarH.java
@@ -17,30 +17,29 @@
 
 package com.io7m.jsycamore.components.standard.internal.scrollbars;
 
-import com.io7m.jattribute.core.AttributeType;
 import com.io7m.jregions.core.parameterized.areas.PAreasI;
 import com.io7m.jregions.core.parameterized.sizes.PAreaSizeI;
 import com.io7m.jsycamore.api.components.SyButtonReadableType;
 import com.io7m.jsycamore.api.components.SyComponentReadableType;
 import com.io7m.jsycamore.api.components.SyConstraints;
 import com.io7m.jsycamore.api.components.SyScrollBarDrag;
+import com.io7m.jsycamore.api.components.SyScrollBarHideIfDisabled;
 import com.io7m.jsycamore.api.components.SyScrollBarHorizontalType;
-import com.io7m.jsycamore.api.components.SyScrollBarPresencePolicy;
 import com.io7m.jsycamore.api.events.SyEventConsumed;
 import com.io7m.jsycamore.api.events.SyEventType;
 import com.io7m.jsycamore.api.layout.SyLayoutContextType;
 import com.io7m.jsycamore.api.spaces.SySpaceParentRelativeType;
 import com.io7m.jsycamore.api.themes.SyThemeClassNameType;
 import com.io7m.jsycamore.components.standard.SyComponentAbstract;
-import com.io7m.jsycamore.components.standard.SyComponentAttributes;
 import com.io7m.jtensors.core.parameterized.vectors.PVector2I;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.function.Consumer;
 
 import static com.io7m.jsycamore.api.active.SyActive.ACTIVE;
 import static com.io7m.jsycamore.api.active.SyActive.INACTIVE;
-import static com.io7m.jsycamore.api.components.SyScrollBarPresencePolicy.DISABLED_IF_ENTIRE_RANGE_SHOWN;
+import static com.io7m.jsycamore.api.components.SyScrollBarHideIfDisabled.HIDE_IF_DISABLED;
 import static com.io7m.jsycamore.api.events.SyEventConsumed.EVENT_NOT_CONSUMED;
 
 /**
@@ -57,7 +56,8 @@ public final class SyScrollBarH
   private final SyScrollBarHButtonLeft buttonLeft;
   private final SyScrollBarHButtonRight buttonRight;
   private final SyScrollBarHTrack track;
-  private final AttributeType<SyScrollBarPresencePolicy> presencePolicy;
+  private SyScrollBarHideIfDisabled hideIfDisabled =
+    SyScrollBarHideIfDisabled.SHOW_EVEN_IF_DISABLED;
 
   /**
    * A horizontal scrollbar.
@@ -70,9 +70,6 @@ public SyScrollBarH(
   {
     super(inThemeClassesExtra);
 
-    this.presencePolicy =
-      SyComponentAttributes.get().create(DISABLED_IF_ENTIRE_RANGE_SHOWN);
-
     this.buttonLeft =
       new SyScrollBarHButtonLeft();
     this.buttonRight =
@@ -90,6 +87,19 @@ public PAreaSizeI<SySpaceParentRelativeType> layout(
     final SyLayoutContextType layoutContext,
     final SyConstraints constraints)
   {
+    /*
+     * Scrollbars are able to hide themselves by collapsing to zero size.
+     */
+
+    if (this.hideIfDisabled == HIDE_IF_DISABLED) {
+      if (!this.isActive()) {
+        final var zero =
+          PAreaSizeI.<SySpaceParentRelativeType>of(0, 0);
+        this.setSize(zero);
+        return zero;
+      }
+    }
+
     var limitedConstraints =
       layoutContext.deriveThemeConstraints(constraints, this);
 
@@ -262,6 +272,14 @@ public double scrollIncrementSize()
     return this.track.scrollIncrementSize();
   }
 
+  @Override
+  public void setHideIfDisabled(
+    final SyScrollBarHideIfDisabled newHideIfDisabled)
+  {
+    this.hideIfDisabled =
+      Objects.requireNonNull(newHideIfDisabled, "newHideIfDisabled");
+  }
+
   @Override
   public void setScrollPosition(
     final double position)
@@ -281,23 +299,7 @@ public void setScrollAmountShown(
     final double amount)
   {
     this.track.setScrollAmountShown(amount);
-
-    final var all =
-      this.track.scrollAmountShown() >= 1.0;
-
-    final var active =
-      switch (this.presencePolicy.get()) {
-        case ALWAYS_ENABLED -> {
-          yield ACTIVE;
-        }
-        case DISABLED_IF_ENTIRE_RANGE_SHOWN -> {
-          yield all ? INACTIVE : ACTIVE;
-        }
-      };
-
-    this.buttonLeft.setActive(active);
-    this.buttonRight.setActive(active);
-    this.track.setActive(active);
+    this.setActive(this.track.scrollAmountShown() >= 1.0 ? INACTIVE : ACTIVE);
   }
 
   @Override
@@ -325,20 +327,20 @@ public SyComponentReadableType track()
   }
 
   @Override
-  public double scrollPosition()
+  public double scrollAmountShown()
   {
-    return this.track.scrollPosition();
+    return this.track.scrollAmountShown();
   }
 
   @Override
-  public double scrollPositionSnapping()
+  public double scrollPosition()
   {
-    return this.track.scrollPositionSnapping();
+    return this.track.scrollPosition();
   }
 
   @Override
-  public AttributeType<SyScrollBarPresencePolicy> presencePolicy()
+  public double scrollPositionSnapping()
   {
-    return this.presencePolicy;
+    return this.track.scrollPositionSnapping();
   }
 }
diff --git a/...rc/main/java/com/io7m/jsycamore/components/standard/internal/scrollbars/SyScrollBarV.java b/...rc/main/java/com/io7m/jsycamore/components/standard/internal/scrollbars/SyScrollBarV.java
@@ -17,30 +17,29 @@
 
 package com.io7m.jsycamore.components.standard.internal.scrollbars;
 
-import com.io7m.jattribute.core.AttributeType;
 import com.io7m.jregions.core.parameterized.areas.PAreasI;
 import com.io7m.jregions.core.parameterized.sizes.PAreaSizeI;
 import com.io7m.jsycamore.api.components.SyButtonReadableType;
 import com.io7m.jsycamore.api.components.SyComponentReadableType;
 import com.io7m.jsycamore.api.components.SyConstraints;
 import com.io7m.jsycamore.api.components.SyScrollBarDrag;
-import com.io7m.jsycamore.api.components.SyScrollBarPresencePolicy;
+import com.io7m.jsycamore.api.components.SyScrollBarHideIfDisabled;
 import com.io7m.jsycamore.api.components.SyScrollBarVerticalType;
 import com.io7m.jsycamore.api.events.SyEventConsumed;
 import com.io7m.jsycamore.api.events.SyEventType;
 import com.io7m.jsycamore.api.layout.SyLayoutContextType;
 import com.io7m.jsycamore.api.spaces.SySpaceParentRelativeType;
 import com.io7m.jsycamore.api.themes.SyThemeClassNameType;
 import com.io7m.jsycamore.components.standard.SyComponentAbstract;
-import com.io7m.jsycamore.components.standard.SyComponentAttributes;
 import com.io7m.jtensors.core.parameterized.vectors.PVector2I;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.function.Consumer;
 
 import static com.io7m.jsycamore.api.active.SyActive.ACTIVE;
 import static com.io7m.jsycamore.api.active.SyActive.INACTIVE;
-import static com.io7m.jsycamore.api.components.SyScrollBarPresencePolicy.DISABLED_IF_ENTIRE_RANGE_SHOWN;
+import static com.io7m.jsycamore.api.components.SyScrollBarHideIfDisabled.HIDE_IF_DISABLED;
 import static com.io7m.jsycamore.api.events.SyEventConsumed.EVENT_NOT_CONSUMED;
 
 /**
@@ -57,7 +56,8 @@ public final class SyScrollBarV
   private final SyScrollBarVButtonUp buttonUp;
   private final SyScrollBarVButtonDown buttonDown;
   private final SyScrollBarVTrack track;
-  private final AttributeType<SyScrollBarPresencePolicy> presencePolicy;
+  private SyScrollBarHideIfDisabled hideIfDisabled =
+    SyScrollBarHideIfDisabled.SHOW_EVEN_IF_DISABLED;
 
   /**
    * A vertical scrollbar.
@@ -70,9 +70,6 @@ public SyScrollBarV(
   {
     super(inThemeClassesExtra);
 
-    this.presencePolicy =
-      SyComponentAttributes.get().create(DISABLED_IF_ENTIRE_RANGE_SHOWN);
-
     this.buttonUp =
       new SyScrollBarVButtonUp();
     this.buttonDown =
@@ -90,6 +87,19 @@ public PAreaSizeI<SySpaceParentRelativeType> layout(
     final SyLayoutContextType layoutContext,
     final SyConstraints constraints)
   {
+    /*
+     * Scrollbars are able to hide themselves by collapsing to zero size.
+     */
+
+    if (this.hideIfDisabled == HIDE_IF_DISABLED) {
+      if (!this.isActive()) {
+        final var zero =
+          PAreaSizeI.<SySpaceParentRelativeType>of(0, 0);
+        this.setSize(zero);
+        return zero;
+      }
+    }
+
     var limitedConstraints =
       layoutContext.deriveThemeConstraints(constraints, this);
 
@@ -249,23 +259,7 @@ public void setScrollAmountShown(
     final double amount)
   {
     this.track.setScrollAmountShown(amount);
-
-    final var all =
-      this.track.scrollAmountShown() >= 1.0;
-
-    final var active =
-      switch (this.presencePolicy.get()) {
-        case ALWAYS_ENABLED -> {
-          yield ACTIVE;
-        }
-        case DISABLED_IF_ENTIRE_RANGE_SHOWN -> {
-          yield all ? INACTIVE : ACTIVE;
-        }
-      };
-
-    this.buttonUp.setActive(active);
-    this.buttonDown.setActive(active);
-    this.track.setActive(active);
+    this.setActive(this.track.scrollAmountShown() >= 1.0 ? INACTIVE : ACTIVE);
   }
 
   @Override
@@ -292,6 +286,12 @@ public SyComponentReadableType track()
     return this.track;
   }
 
+  @Override
+  public double scrollAmountShown()
+  {
+    return this.track.scrollAmountShown();
+  }
+
   @Override
   public double scrollPosition()
   {
@@ -310,12 +310,6 @@ public double scrollIncrementSize()
     return this.track.scrollIncrementSize();
   }
 
-  @Override
-  public AttributeType<SyScrollBarPresencePolicy> presencePolicy()
-  {
-    return this.presencePolicy;
-  }
-
   @Override
   public void setOnClickUpListener(
     final Runnable runnable)
@@ -341,4 +335,12 @@ public void removeOnClickDownListener()
   {
     this.buttonDown.removeOnClickListener();
   }
+
+  @Override
+  public void setHideIfDisabled(
+    final SyScrollBarHideIfDisabled newHideIfDisabled)
+  {
+    this.hideIfDisabled =
+      Objects.requireNonNull(newHideIfDisabled, "newHideIfDisabled");
+  }
 }