1/*
2 * Copyright (C) 2008 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.widget;
18
19import android.annotation.Widget;
20import android.content.Context;
21import android.util.AttributeSet;
22import android.view.LayoutInflater;
23import android.view.MotionEvent;
24import android.view.View;
25import android.view.accessibility.AccessibilityEvent;
26import android.view.accessibility.AccessibilityNodeInfo;
27import android.view.animation.AlphaAnimation;
28
29import com.android.internal.R;
30
31
32/**
33 * The {@code ZoomControls} class displays a simple set of controls used for zooming and
34 * provides callbacks to register for events. */
35@Widget
36public class ZoomControls extends LinearLayout {
37
38    private final ZoomButton mZoomIn;
39    private final ZoomButton mZoomOut;
40
41    public ZoomControls(Context context) {
42        this(context, null);
43    }
44
45    public ZoomControls(Context context, AttributeSet attrs) {
46        super(context, attrs);
47        setFocusable(false);
48
49        LayoutInflater inflater = (LayoutInflater) context
50                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
51        inflater.inflate(R.layout.zoom_controls, this, // we are the parent
52                true);
53
54        mZoomIn = (ZoomButton) findViewById(R.id.zoomIn);
55        mZoomOut = (ZoomButton) findViewById(R.id.zoomOut);
56    }
57
58    public void setOnZoomInClickListener(OnClickListener listener) {
59        mZoomIn.setOnClickListener(listener);
60    }
61
62    public void setOnZoomOutClickListener(OnClickListener listener) {
63        mZoomOut.setOnClickListener(listener);
64    }
65
66    /*
67     * Sets how fast you get zoom events when the user holds down the
68     * zoom in/out buttons.
69     */
70    public void setZoomSpeed(long speed) {
71        mZoomIn.setZoomSpeed(speed);
72        mZoomOut.setZoomSpeed(speed);
73    }
74
75    @Override
76    public boolean onTouchEvent(MotionEvent event) {
77
78        /* Consume all touch events so they don't get dispatched to the view
79         * beneath this view.
80         */
81        return true;
82    }
83
84    public void show() {
85        fade(View.VISIBLE, 0.0f, 1.0f);
86    }
87
88    public void hide() {
89        fade(View.GONE, 1.0f, 0.0f);
90    }
91
92    private void fade(int visibility, float startAlpha, float endAlpha) {
93        AlphaAnimation anim = new AlphaAnimation(startAlpha, endAlpha);
94        anim.setDuration(500);
95        startAnimation(anim);
96        setVisibility(visibility);
97    }
98
99    public void setIsZoomInEnabled(boolean isEnabled) {
100        mZoomIn.setEnabled(isEnabled);
101    }
102
103    public void setIsZoomOutEnabled(boolean isEnabled) {
104        mZoomOut.setEnabled(isEnabled);
105    }
106
107    @Override
108    public boolean hasFocus() {
109        return mZoomIn.hasFocus() || mZoomOut.hasFocus();
110    }
111
112    @Override
113    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
114        super.onInitializeAccessibilityEvent(event);
115        event.setClassName(ZoomControls.class.getName());
116    }
117
118    @Override
119    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
120        super.onInitializeAccessibilityNodeInfo(info);
121        info.setClassName(ZoomControls.class.getName());
122    }
123}
124