RotateLayout.java revision 94ca8baae7e6e3885d895c095890eabf30d922e2 
1/*
2 * Copyright (C) 2010 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 com.android.camera.ui;
18
19import com.android.camera.ui.Rotatable;
20
21import android.content.Context;
22import android.util.AttributeSet;
23import android.view.View;
24import android.view.ViewGroup;
25
26// A RotateLayout is designed to display a single item and provides the
27// capabilities to rotate the item.
28public class RotateLayout extends ViewGroup implements Rotatable {
29    private static final String TAG = "RotateLayout";
30    private int mOrientation;
31    private View mChild;
32
33    public RotateLayout(Context context, AttributeSet attrs) {
34        super(context, attrs);
35        // The transparent background here is a workaround of the render issue
36        // happened when the view is rotated as the device's orientation
37        // changed. The view looks fine in landscape. After rotation, the view
38        // is invisible.
39        setBackgroundResource(android.R.color.transparent);
40    }
41
42    @Override
43    protected void onFinishInflate() {
44        mChild = getChildAt(0);
45        mChild.setPivotX(0);
46        mChild.setPivotY(0);
47    }
48
49    @Override
50    protected void onLayout(
51            boolean change, int left, int top, int right, int bottom) {
52        int width = right - left;
53        int height = bottom - top;
54        switch (mOrientation) {
55            case 0:
56            case 180:
57                mChild.layout(0, 0, width, height);
58                break;
59            case 90:
60            case 270:
61                mChild.layout(0, 0, height, width);
62                break;
63        }
64    }
65
66    @Override
67    protected void onMeasure(int widthSpec, int heightSpec) {
68        int w = 0, h = 0;
69        switch(mOrientation) {
70            case 0:
71            case 180:
72                measureChild(mChild, widthSpec, heightSpec);
73                w = mChild.getMeasuredWidth();
74                h = mChild.getMeasuredHeight();
75                break;
76            case 90:
77            case 270:
78                measureChild(mChild, heightSpec, widthSpec);
79                w = mChild.getMeasuredHeight();
80                h = mChild.getMeasuredWidth();
81                break;
82        }
83        setMeasuredDimension(w, h);
84
85        switch (mOrientation) {
86            case 0:
87                mChild.setTranslationX(0);
88                mChild.setTranslationY(0);
89                break;
90            case 90:
91                mChild.setTranslationX(0);
92                mChild.setTranslationY(h);
93                break;
94            case 180:
95                mChild.setTranslationX(w);
96                mChild.setTranslationY(h);
97                break;
98            case 270:
99                mChild.setTranslationX(w);
100                mChild.setTranslationY(0);
101                break;
102        }
103        mChild.setRotation(-mOrientation);
104    }
105
106    // Rotate the view counter-clockwise
107    public void setOrientation(int orientation) {
108        orientation = orientation % 360;
109        if (mOrientation == orientation) return;
110        mOrientation = orientation;
111        requestLayout();
112    }
113}
114