1/*
2 * Copyright (C) 2006 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.graphics;
18
19public class RegionIterator {
20
21    /**
22     * Construct an iterator for all of the rectangles in a region. This
23     * effectively makes a private copy of the region, so any subsequent edits
24     * to region will not affect the iterator.
25     *
26     * @param region the region that will be iterated
27     */
28    public RegionIterator(Region region) {
29        mNativeIter = nativeConstructor(region.ni());
30    }
31
32    /**
33     * Return the next rectangle in the region. If there are no more rectangles
34     * this returns false and r is unchanged. If there is at least one more,
35     * this returns true and r is set to that rectangle.
36     */
37    public final boolean next(Rect r) {
38        if (r == null) {
39            throw new NullPointerException("The Rect must be provided");
40        }
41        return nativeNext(mNativeIter, r);
42    }
43
44    protected void finalize() throws Throwable {
45        nativeDestructor(mNativeIter);
46        mNativeIter = 0;  // Other finalizers can still call us.
47    }
48
49    private static native long nativeConstructor(long native_region);
50    private static native void nativeDestructor(long native_iter);
51    private static native boolean nativeNext(long native_iter, Rect r);
52
53    private long mNativeIter;
54}
55
56