Initial checkin of AOSP Messaging app.

b/23110861

Change-Id: I11db999bd10656801e618f78ab2b2ef74136fff1

src/com/android/messaging/ui/PlaceholderInsetDrawable.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.messaging.ui;
+
+import android.graphics.drawable.Drawable;
+import android.graphics.drawable.InsetDrawable;
+
+/**
+ * A "placeholder" drawable that has the same sizing properties as the real UI element it
+ * replaces.
+ *
+ * This is an InsetDrawable that takes a placeholder drawable (an animation list, or simply
+ * a color drawable) and place it in the center of the inset drawable that's sized to the
+ * requested source width and height of the image that it replaces. Unlike the base
+ * InsetDrawable, this implementation returns the true width and height of the real image
+ * that it's placeholding, instead of the intrinsic size of the contained drawable, so that
+ * when used in an ImageView, it may be positioned/scaled/cropped the same way the real
+ * image is.
+ */
+public class PlaceholderInsetDrawable extends InsetDrawable {
+    // The dimensions of the real image that this drawable is replacing.
+    private final int mSourceWidth;
+    private final int mSourceHeight;
+
+    /**
+     * Given a source drawable, wraps it around in this placeholder drawable by placing the
+     * drawable at the center of the container if possible (or fill the container if the
+     * drawable doesn't have intrinsic size such as color drawable).
+     */
+    public static PlaceholderInsetDrawable fromDrawable(final Drawable drawable,
+            final int sourceWidth, final int sourceHeight) {
+        final int drawableWidth = drawable.getIntrinsicWidth();
+        final int drawableHeight = drawable.getIntrinsicHeight();
+        final int insetHorizontal = drawableWidth < 0 || drawableWidth > sourceWidth ?
+                0 : (sourceWidth - drawableWidth) / 2;
+        final int insetVertical = drawableHeight < 0 || drawableHeight > sourceHeight ?
+                0 : (sourceHeight - drawableHeight) / 2;
+        return new PlaceholderInsetDrawable(drawable, insetHorizontal, insetVertical,
+                insetHorizontal, insetVertical, sourceWidth, sourceHeight);
+    }
+
+    private PlaceholderInsetDrawable(final Drawable drawable, final int insetLeft,
+            final int insetTop, final int insetRight, final int insetBottom,
+            final int sourceWidth, final int sourceHeight) {
+        super(drawable, insetLeft, insetTop, insetRight, insetBottom);
+        mSourceWidth = sourceWidth;
+        mSourceHeight = sourceHeight;
+    }
+
+    @Override
+    public int getIntrinsicWidth() {
+        return mSourceWidth;
+    }
+
+    @Override
+    public int getIntrinsicHeight() {
+        return mSourceHeight;
+    }
+}