src/com/android/gallery3d/ui/NinePatchChunk.java

/*
 * Copyright (C) 2010 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.gallery3d.ui;

import android.graphics.Rect;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

// See "frameworks/base/include/utils/ResourceTypes.h" for the format of
// NinePatch chunk.
class NinePatchChunk {

    public static final int NO_COLOR = 0x00000001;
    public static final int TRANSPARENT_COLOR = 0x00000000;

    public Rect mPaddings = new Rect();

    public int mDivX[];
    public int mDivY[];
    public int mColor[];

    private static void readIntArray(int[] data, ByteBuffer buffer) {
        for (int i = 0, n = data.length; i < n; ++i) {
            data[i] = buffer.getInt();
        }
    }

    private static void checkDivCount(int length) {
        if (length == 0 || (length & 0x01) != 0) {
            throw new RuntimeException("invalid nine-patch: " + length);
        }
    }

    public static NinePatchChunk deserialize(byte[] data) {
        ByteBuffer byteBuffer =
                ByteBuffer.wrap(data).order(ByteOrder.nativeOrder());

        byte wasSerialized = byteBuffer.get();
        if (wasSerialized == 0) return null;

        NinePatchChunk chunk = new NinePatchChunk();
        chunk.mDivX = new int[byteBuffer.get()];
        chunk.mDivY = new int[byteBuffer.get()];
        chunk.mColor = new int[byteBuffer.get()];

        checkDivCount(chunk.mDivX.length);
        checkDivCount(chunk.mDivY.length);

        // skip 8 bytes
        byteBuffer.getInt();
        byteBuffer.getInt();

        chunk.mPaddings.left = byteBuffer.getInt();
        chunk.mPaddings.right = byteBuffer.getInt();
        chunk.mPaddings.top = byteBuffer.getInt();
        chunk.mPaddings.bottom = byteBuffer.getInt();

        // skip 4 bytes
        byteBuffer.getInt();

        readIntArray(chunk.mDivX, byteBuffer);
        readIntArray(chunk.mDivY, byteBuffer);
        readIntArray(chunk.mColor, byteBuffer);

        return chunk;
    }
}