Incorporating a minimum and maximum size for the square layout to kee…

…p images from getting too large on tablets.

ActivitySceneTransitionBasic/app/src/main/java/com/example/android/activityscenetransitionbasic/SquareFrameLayout.java

@@ -17,6 +17,8 @@
 package com.example.android.activityscenetransitionbasic;
 
 import android.content.Context;
+import android.content.res.TypedArray;
+import android.os.Build;
 import android.util.AttributeSet;
 import android.widget.FrameLayout;
 
@@ -25,6 +27,8 @@
  */
 public class SquareFrameLayout extends FrameLayout {
 
+    private int mMaxWidth, mMaxHeight;
+
     public SquareFrameLayout(Context context) {
         this(context, null);
     }
@@ -35,6 +39,24 @@ public SquareFrameLayout(Context context, AttributeSet attrs) {
 
     public SquareFrameLayout(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);
+
+        TypedArray a = context.getTheme().obtainStyledAttributes(
+            attrs, R.styleable.SquareFrameLayout, 0, 0
+        );
+        try {
+            mMaxWidth = a.getDimensionPixelSize(R.styleable.SquareFrameLayout_maxWidth, Integer.MAX_VALUE);
+            mMaxHeight = a.getDimensionPixelSize(R.styleable.SquareFrameLayout_maxHeight, Integer.MAX_VALUE);
+        } finally {
+            a.recycle();
+        }
+    }
+
+    public int getMaximumWidth() {
+        return mMaxWidth;
+    }
+
+    public int getMaximumHeight() {
+        return mMaxHeight;
     }
 
     @Override
@@ -52,7 +74,7 @@ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
             return;
         }
 
-        final int size;
+        int size;
         if (widthSize == 0 || heightSize == 0) {
             // If one of the dimensions has no restriction on size, set both dimensions to be the
             // on that does
@@ -63,6 +85,17 @@ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
             size = Math.min(widthSize, heightSize);
         }
 
+        // bound the size by the view's min and max dimensions
+        final int maxSize = Math.min(getMaximumWidth(), getMaximumHeight());
+        if (size > maxSize) {
+            size = maxSize;
+        } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
+            final int minSize = Math.max(getMinimumWidth(), getMinimumHeight());
+            if (size < minSize) {
+                size = minSize;
+            }
+        }
+
         final int newMeasureSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY);
         super.onMeasure(newMeasureSpec, newMeasureSpec);
     }

ActivitySceneTransitionBasic/app/src/main/res/layout/details.xml

@@ -16,6 +16,7 @@
 -->
 
 <ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
 
@@ -26,7 +27,9 @@
 
         <com.example.android.activityscenetransitionbasic.SquareFrameLayout
             android:layout_width="match_parent"
-            android:layout_height="wrap_content">
+            android:layout_height="wrap_content"
+            android:minHeight="100dp"
+            app:maxHeight="400dp">
 
             <ImageView
                 android:id="@+id/imageview_header"

ActivitySceneTransitionBasic/app/src/main/res/values/attrs.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <declare-styleable name="SquareFrameLayout">
+        <attr name="maxWidth" format="dimension" />
+        <attr name="maxHeight" format="dimension" />
+    </declare-styleable>
+</resources>