Relative height support

Refactor layout-methods to not use overrideHeight
Adapt retrieve[Min/Max-]Height methods to take priority and relative height into account
Methods for getting the declared (and resolved) height property of a direct parent
Refactor updateHeightsOnSplit to take relative heights into account
Add additional tests

DEVSIX-1389

Author: Samuel Huylebroeck

layout/src/main/java/com/itextpdf/layout/ElementPropertyContainer.java

@@ -169,20 +169,22 @@ public T setWidth(UnitValue width) {
     /**
      * Gets the height property of the Element.
      *
-     * @return the height of the element, as a floating point value.
+     * @return the height of the element, as a floating point value. Null if the property is not present
      */
     public Float getHeight() {
-        return this.<Float>getProperty(Property.HEIGHT);
+        return this.<UnitValue>getProperty(Property.HEIGHT).getValue();
+
     }
 
     /**
-     * Sets the height property of the Element.
+     * Sets the height property of the Element as a point-value.
      *
      * @param height a floating point value for the new height
      * @return this Element.
      */
     public T setHeight(float height) {
-        setProperty(Property.HEIGHT, height);
+        UnitValue heightAsUV = UnitValue.createPointValue(height);
+        setProperty(Property.HEIGHT, heightAsUV);
         return (T) (Object) this;
     }
 

layout/src/main/java/com/itextpdf/layout/element/BlockElement.java

@@ -386,19 +386,36 @@ public T setRotationAngle(double angleInRadians) {
         return (T) (Object) this;
     }
 
+    /**
+     * Sets the height of a block element as point-unit value
+     * @param height a floating point value for the new height
+     * @return the block element itself
+     */
     @Override
     public T setHeight(float height) {
         super.setHeight(height);
         return (T) (Object) this;
     }
 
+    /**
+     * Sets the max-height of a block element as point-unit value.
+     * @param maxHeight a floating point value for the new max-height
+     * @return the block element itself
+     */
     public T setMaxHeight(float maxHeight) {
-        setProperty(Property.MAX_HEIGHT, maxHeight);
+        UnitValue maxHeightAsUV = UnitValue.createPointValue(maxHeight);
+        setProperty(Property.MAX_HEIGHT, maxHeightAsUV);
         return (T) (Object) this;
     }
 
+    /**
+     * Sets the min-height of a block element as point-unit value.
+     * @param minHeight a floating point value for the new min-height
+     * @return the block element itself
+     */
     public T setMinHeight(float minHeight) {
-        setProperty(Property.MIN_HEIGHT, minHeight);
+        UnitValue minHeightAsUV = UnitValue.createPointValue(minHeight);
+        setProperty(Property.MIN_HEIGHT, minHeightAsUV);
         return (T) (Object) this;
     }
 

layout/src/main/java/com/itextpdf/layout/element/Image.java

@@ -55,6 +55,7 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.xobject.PdfXObject;
 import com.itextpdf.layout.property.Property;
 import com.itextpdf.layout.layout.LayoutPosition;
+import com.itextpdf.layout.property.UnitValue;
 import com.itextpdf.layout.renderer.IRenderer;
 import com.itextpdf.layout.renderer.ImageRenderer;
 
@@ -421,12 +422,14 @@ public float getImageHeight() {
     }
 
     public Image setMaxHeight(float maxHeight) {
-        setProperty(Property.MAX_HEIGHT, maxHeight);
+        UnitValue maxHeightAsUv = UnitValue.createPointValue(maxHeight);
+        setProperty(Property.MAX_HEIGHT, maxHeightAsUv);
         return (Image) (Object) this;
     }
 
     public Image setMinHeight(float minHeight) {
-        setProperty(Property.MIN_HEIGHT, minHeight);
+        UnitValue minHeightAsUv = UnitValue.createPointValue(minHeight);
+        setProperty(Property.MIN_HEIGHT, minHeightAsUv);
         return (Image) (Object) this;
     }
 

layout/src/main/java/com/itextpdf/layout/margincollapse/MarginsCollapseHandler.java

@@ -46,6 +46,7 @@ This file is part of the iText (R) project.
 import com.itextpdf.layout.IPropertyContainer;
 import com.itextpdf.layout.property.FloatPropertyValue;
 import com.itextpdf.layout.property.Property;
+import com.itextpdf.layout.property.UnitValue;
 import com.itextpdf.layout.renderer.AbstractRenderer;
 import com.itextpdf.layout.renderer.BlockRenderer;
 import com.itextpdf.layout.renderer.CellRenderer;
@@ -519,11 +520,11 @@ private static boolean hasPositiveHeight(IRenderer renderer) {
         float height = renderer.getOccupiedArea().getBBox().getHeight();
 
         if (height == 0) {
-            Float heightPropVal = renderer.<Float>getProperty(Property.HEIGHT);
-            Float minHeightPropVal = renderer.<Float>getProperty(Property.MIN_HEIGHT);
+            UnitValue heightPropVal = renderer.<UnitValue>getProperty(Property.HEIGHT);
+            UnitValue minHeightPropVal = renderer.<UnitValue>getProperty(Property.MIN_HEIGHT);
             height = minHeightPropVal != null
-                    ? (float) minHeightPropVal
-                    : heightPropVal != null ? (float) heightPropVal : 0;
+                    ? (float) minHeightPropVal.getValue()
+                    : heightPropVal != null ? (float) heightPropVal.getValue() : 0;
         }
         return height > 0;
     }