General cleanup

- Removed unused resources
- Cleaned up styles (mostly removing default stuff)
- Improved and corrected method documentation
- Minor refactoring of min method

Author: ToxicBakery

ViewPagerTransformsExample/AndroidManifest.xml

@@ -12,7 +12,7 @@
         android:allowBackup="true"
         android:icon="@drawable/ic_launcher"
         android:label="@string/app_name"
-        android:theme="@style/AppTheme" >
+        android:theme="@style/AppBaseTheme" >
         <activity
             android:name="com.ToxicBakery.viewpager.transforms.example.MainActivity"
             android:label="@string/app_name" >

ViewPagerTransformsExample/libs/android-support-v13.jar

@@ -3,11 +3,7 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:gravity="center"
-    android:paddingBottom="@dimen/activity_vertical_margin"
-    android:paddingLeft="@dimen/activity_horizontal_margin"
-    android:paddingRight="@dimen/activity_horizontal_margin"
-    android:paddingTop="@dimen/activity_vertical_margin"
     android:text="@string/app_name"
-    android:textColor="?android:attr/colorBackground"
+    android:textColor="@android:color/white"
     android:textSize="72sp"
     tools:context="com.ToxicBakery.viewpager.transforms.example.MainActivity$PlaceholderFragment" />

ViewPagerTransformsExample/res/drawable-hdpi/ic_launcher.png

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <style name="AppBaseTheme" parent="android:Theme.Holo">
+        <item name="android:windowBackground">@android:color/background_light</item>
+        <item name="android:actionBarStyle">@style/DarkActionBar</item>
+    </style>
+
+    <style name="DarkActionBar" parent="@android:style/Widget.Holo.ActionBar">
+        <item name="android:background">@android:color/background_dark</item>
+    </style>
+
+</resources>

ViewPagerTransformsExample/res/drawable-mdpi/ic_launcher.png

@@ -41,23 +41,23 @@ public class MainActivity extends Activity implements OnNavigationListener {
 	private static final ArrayList<TransformerItem> TRANSFORM_CLASSES;
 
 	static {
-		TRANSFORM_CLASSES = new ArrayList<>();
+		TRANSFORM_CLASSES = new ArrayList<TransformerItem>();
 		TRANSFORM_CLASSES.add(new TransformerItem(DefaultTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(AccordionTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(BackgroundToForegroundTransformer.class));
-		TRANSFORM_CLASSES.add(new TransformerItem(DepthPageTransformer.class));
-		TRANSFORM_CLASSES.add(new TransformerItem(ForegroundToBackgroundTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(CubeInTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(CubeOutTransformer.class));
+		TRANSFORM_CLASSES.add(new TransformerItem(DepthPageTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(FlipHorizontalTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(FlipVerticalTransformer.class));
+		TRANSFORM_CLASSES.add(new TransformerItem(ForegroundToBackgroundTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(RotateDownTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(RotateUpTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(StackTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(TabletTransformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(ZoomInTransformer.class));
-		TRANSFORM_CLASSES.add(new TransformerItem(ZoomOutTranformer.class));
 		TRANSFORM_CLASSES.add(new TransformerItem(ZoomOutSlideTransformer.class));
+		TRANSFORM_CLASSES.add(new TransformerItem(ZoomOutTranformer.class));
 	}
 
 	private int mSelectedItem;
@@ -74,8 +74,8 @@ protected void onCreate(Bundle savedInstanceState) {
 			selectedPage = savedInstanceState.getInt(KEY_SELECTED_PAGE);
 		}
 
-		final ArrayAdapter<TransformerItem> actionBarAdapter = new ArrayAdapter<>(getApplicationContext(),
-				android.R.layout.simple_list_item_1, android.R.id.text1, TRANSFORM_CLASSES);
+		final ArrayAdapter<TransformerItem> actionBarAdapter = new ArrayAdapter<TransformerItem>(
+				getApplicationContext(), android.R.layout.simple_list_item_1, android.R.id.text1, TRANSFORM_CLASSES);
 
 		final ActionBar actionBar = getActionBar();
 		actionBar.setListNavigationCallbacks(actionBarAdapter, this);

ViewPagerTransformsExample/res/layout/fragment_main.xml

@@ -8,21 +8,34 @@ public abstract class ABaseTransformer implements PageTransformer {
 	/**
 	 * Called each {@link #transformPage(View, float)}.
 	 * 
-	 * @param view
+	 * @param page
+	 *            Apply the transformation to this page
 	 * @param position
+	 *            Position of page relative to the current front-and-center position of the pager. 0 is front and
+	 *            center. 1 is one full page position to the right, and -1 is one page position to the left.
 	 */
-	protected abstract void onTransform(View view, float position);
+	protected abstract void onTransform(View page, float position);
 
+	/**
+	 * Apply a property transformation to the given page. For most use cases, this method should not be overridden.
+	 * Instead use {@link #transformPage(View, float)} to perform typical transformations.
+	 * 
+	 * @param page
+	 *            Apply the transformation to this page
+	 * @param position
+	 *            Position of page relative to the current front-and-center position of the pager. 0 is front and
+	 *            center. 1 is one full page position to the right, and -1 is one page position to the left.
+	 */
 	@Override
-	public void transformPage(View view, float position) {
-		onPreTransform(view, position);
-		onTransform(view, position);
-		onPostTransform(view, position);
+	public void transformPage(View page, float position) {
+		onPreTransform(page, position);
+		onTransform(page, position);
+		onPostTransform(page, position);
 	}
 
 	/**
 	 * If the position offset of a fragment is less than negative one or greater than one, returning true will set the
-	 * visibility of the fragment to {@link View#GONE}. Returning false will force the fragment to {@link View#VISIBLE}.
+	 * fragment alpha to 0f. Otherwise fragment alpha is always defaulted to 1f.
 	 * 
 	 * @return
 	 */
@@ -40,38 +53,60 @@ protected boolean isPagingEnabled() {
 	}
 
 	/**
-	 * Called each {@link #transformPage(View, float)} before {{@link #onTransform(View, float)} is called.
+	 * Called each {@link #transformPage(View, float)} before {{@link #onTransform(View, float)}.
+	 * <p>
+	 * The default implementation attempts to reset all view properties. This is useful when toggling transforms that do
+	 * not modify the same page properties. For instance changing from a transformation that applies rotation to a
+	 * transformation that fades can inadvertently leave a fragment stuck with a rotation or with some degree of applied
+	 * alpha.
 	 * 
-	 * @param view
+	 * @param page
+	 *            Apply the transformation to this page
 	 * @param position
+	 *            Position of page relative to the current front-and-center position of the pager. 0 is front and
+	 *            center. 1 is one full page position to the right, and -1 is one page position to the left.
 	 */
-	protected void onPreTransform(View view, float position) {
-		final float width = view.getWidth();
+	protected void onPreTransform(View page, float position) {
+		final float width = page.getWidth();
 
-		view.setRotationX(0);
-		view.setRotationY(0);
-		view.setRotation(0);
-		view.setScaleX(1);
-		view.setScaleY(1);
-		view.setPivotX(0);
-		view.setPivotY(0);
-		view.setTranslationY(0);
-		view.setTranslationX(isPagingEnabled() ? 0f : -width * position);
+		page.setRotationX(0);
+		page.setRotationY(0);
+		page.setRotation(0);
+		page.setScaleX(1);
+		page.setScaleY(1);
+		page.setPivotX(0);
+		page.setPivotY(0);
+		page.setTranslationY(0);
+		page.setTranslationX(isPagingEnabled() ? 0f : -width * position);
 
 		if (hideOffscreenPages()) {
-			view.setAlpha(position <= -1f || position >= 1f ? 0f : 1f);
+			page.setAlpha(position <= -1f || position >= 1f ? 0f : 1f);
 		} else {
-			view.setAlpha(1f);
+			page.setAlpha(1f);
 		}
 	}
 
 	/**
-	 * Called each {@link #transformPage(View, float)} call after {@link #onTransform(View, float)} is finished.
+	 * Called each {@link #transformPage(View, float)} after {@link #onTransform(View, float)}.
 	 * 
-	 * @param view
+	 * @param page
+	 *            Apply the transformation to this page
 	 * @param position
+	 *            Position of page relative to the current front-and-center position of the pager. 0 is front and
+	 *            center. 1 is one full page position to the right, and -1 is one page position to the left.
+	 */
+	protected void onPostTransform(View page, float position) {
+	}
+
+	/**
+	 * Same as {@link Math#min(double, double)} without double casting, zero closest to infinity handling, or NaN support.
+	 * 
+	 * @param val
+	 * @param min
+	 * @return
 	 */
-	protected void onPostTransform(View view, float position) {
+	protected static final float min(float val, float min) {
+		return val < min ? min : val;
 	}
 
 }

ViewPagerTransformsExample/res/values-w820dp/dimens.xml

@@ -17,8 +17,4 @@ protected void onTransform(View view, float position) {
 		view.setTranslationX(position < 0 ? width * position : -width * position * 0.25f);
 	}
 
-	private static final float min(float val, float min) {
-		return val < min ? min : val;
-	}
-
 }

ViewPagerTransformsExample/res/values/dimens.xml

@@ -17,8 +17,4 @@ protected void onTransform(View view, float position) {
 		view.setTranslationX(position > 0 ? width * position : -width * position * 0.25f);
 	}
 
-	private static final float min(float val, float min) {
-		return val < min ? min : val;
-	}
-
 }