Skip 2nd measure pass whenever possible

If the height measured during the horizontal pass fits within the
constraints of the vertical pass we can skip the second call to
child.measure().

Change-Id: I3aebf78967e5920ffb28bbe8985ca7a426327a82

1 files changed, 21 insertions, 23 deletions

diff --git a/core/java/android/widget/RelativeLayout.java b/core/java/android/widget/RelativeLayout.java
index f940226a1a60..77ffdaf6efc8 100644
--- a/core/java/android/widget/RelativeLayout.java
+++ b/core/java/android/widget/RelativeLayout.java
@@ -394,8 +394,6 @@ public class RelativeLayout extends ViewGroup {
         }        
     }
 
-    // TODO: we need to find another way to implement RelativeLayout
-    // This implementation cannot handle every case
     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         if (mDirtyHierarchy) {
@@ -685,16 +683,28 @@ public class RelativeLayout extends ViewGroup {
      * @param myHeight Height of the RelativeLayout
      */
     private void measureChild(View child, LayoutParams params, int myWidth, int myHeight) {
-        int childWidthMeasureSpec = getChildMeasureSpec(params.mLeft,
-                params.mRight, params.width,
-                params.leftMargin, params.rightMargin,
-                mPaddingLeft, mPaddingRight,
-                myWidth);
         int childHeightMeasureSpec = getChildMeasureSpec(params.mTop,
                 params.mBottom, params.height,
                 params.topMargin, params.bottomMargin,
                 mPaddingTop, mPaddingBottom,
                 myHeight);
+        switch (MeasureSpec.getMode(childHeightMeasureSpec)) {
+            case MeasureSpec.AT_MOST:
+                if (child.getMeasuredHeight() <= MeasureSpec.getSize(childHeightMeasureSpec)) {
+                    return;
+                }
+                break;
+            case MeasureSpec.EXACTLY:
+                if (child.getMeasuredHeight() == MeasureSpec.getSize(childHeightMeasureSpec)) {
+                    return;
+                }
+                break;
+        }
+        int childWidthMeasureSpec = getChildMeasureSpec(params.mLeft,
+                params.mRight, params.width,
+                params.leftMargin, params.rightMargin,
+                mPaddingLeft, mPaddingRight,
+                myWidth);
         child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
     }
 
@@ -900,8 +910,6 @@ public class RelativeLayout extends ViewGroup {
         } else if (childParams.alignWithParent && rules[LEFT_OF] != 0) {
             if (myWidth >= 0) {
                 childParams.mRight = myWidth - mPaddingRight - childParams.rightMargin;
-            } else {
-                // FIXME uh oh...
             }
         }
 
@@ -926,20 +934,16 @@ public class RelativeLayout extends ViewGroup {
         } else if (childParams.alignWithParent && rules[ALIGN_RIGHT] != 0) {
             if (myWidth >= 0) {
                 childParams.mRight = myWidth - mPaddingRight - childParams.rightMargin;
-            } else {
-                // FIXME uh oh...
             }
         }
 
-        if (0 != rules[ALIGN_PARENT_LEFT]) {
+        if (rules[ALIGN_PARENT_LEFT] != 0) {
             childParams.mLeft = mPaddingLeft + childParams.leftMargin;
         }
 
-        if (0 != rules[ALIGN_PARENT_RIGHT]) {
+        if (rules[ALIGN_PARENT_RIGHT] != 0) {
             if (myWidth >= 0) {
                 childParams.mRight = myWidth - mPaddingRight - childParams.rightMargin;
-            } else {
-                // FIXME uh oh...
             }
         }
     }
@@ -958,8 +962,6 @@ public class RelativeLayout extends ViewGroup {
         } else if (childParams.alignWithParent && rules[ABOVE] != 0) {
             if (myHeight >= 0) {
                 childParams.mBottom = myHeight - mPaddingBottom - childParams.bottomMargin;
-            } else {
-                // FIXME uh oh...
             }
         }
 
@@ -984,20 +986,16 @@ public class RelativeLayout extends ViewGroup {
         } else if (childParams.alignWithParent && rules[ALIGN_BOTTOM] != 0) {
             if (myHeight >= 0) {
                 childParams.mBottom = myHeight - mPaddingBottom - childParams.bottomMargin;
-            } else {
-                // FIXME uh oh...
             }
         }
 
-        if (0 != rules[ALIGN_PARENT_TOP]) {
+        if (rules[ALIGN_PARENT_TOP] != 0) {
             childParams.mTop = mPaddingTop + childParams.topMargin;
         }
 
-        if (0 != rules[ALIGN_PARENT_BOTTOM]) {
+        if (rules[ALIGN_PARENT_BOTTOM] != 0) {
             if (myHeight >= 0) {
                 childParams.mBottom = myHeight - mPaddingBottom - childParams.bottomMargin;
-            } else {
-                // FIXME uh oh...
             }
         }