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.widget;
18
19import android.content.Context;
20import android.util.AttributeSet;
21import android.widget.RemoteViews.RemoteView;
22
23
24/**
25 * Represents a push-button widget. Push-buttons can be
26 * pressed, or clicked, by the user to perform an action.
27
28 * <p>A typical use of a push-button in an activity would be the following:
29 * </p>
30 *
31 * <pre>
32 * public class MyActivity extends Activity {
33 *     protected void onCreate(Bundle icicle) {
34 *         super.onCreate(icicle);
35 *
36 *         setContentView(R.layout.content_layout_id);
37 *
38 *         final Button button = (Button) findViewById(R.id.button_id);
39 *         button.setOnClickListener(new View.OnClickListener() {
40 *             public void onClick(View v) {
41 *                 // Perform action on click
42 *             }
43 *         });
44 *     }
45 * }</pre>
46 *
47 * <p>However, instead of applying an {@link android.view.View.OnClickListener OnClickListener} to
48 * the button in your activity, you can assign a method to your button in the XML layout,
49 * using the {@link android.R.attr#onClick android:onClick} attribute. For example:</p>
50 *
51 * <pre>
52 * &lt;Button
53 *     android:layout_height="wrap_content"
54 *     android:layout_width="wrap_content"
55 *     android:text="@string/self_destruct"
56 *     android:onClick="selfDestruct" /&gt;</pre>
57 *
58 * <p>Now, when a user clicks the button, the Android system calls the activity's {@code
59 * selfDestruct(View)} method. In order for this to work, the method must be public and accept
60 * a {@link android.view.View} as its only parameter. For example:</p>
61 *
62 * <pre>
63 * public void selfDestruct(View view) {
64 *     // Kabloey
65 * }</pre>
66 *
67 * <p>The {@link android.view.View} passed into the method is a reference to the widget
68 * that was clicked.</p>
69 *
70 * <h3>Button style</h3>
71 *
72 * <p>Every Button is styled using the system's default button background, which is often different
73 * from one device to another and from one version of the platform to another. If you're not
74 * satisfied with the default button style and want to customize it to match the design of your
75 * application, then you can replace the button's background image with a <a
76 * href="{@docRoot}guide/topics/resources/drawable-resource.html#StateList">state list drawable</a>.
77 * A state list drawable is a drawable resource defined in XML that changes its image based on
78 * the current state of the button. Once you've defined a state list drawable in XML, you can apply
79 * it to your Button with the {@link android.R.attr#background android:background}
80 * attribute. For more information and an example, see <a
81 * href="{@docRoot}guide/topics/resources/drawable-resource.html#StateList">State List
82 * Drawable</a>.</p>
83 *
84 * <p>See the <a href="{@docRoot}guide/topics/ui/controls/button.html">Buttons</a>
85 * guide.</p>
86 *
87 * <p><strong>XML attributes</strong></p>
88 * <p>
89 * See {@link android.R.styleable#Button Button Attributes},
90 * {@link android.R.styleable#TextView TextView Attributes},
91 * {@link android.R.styleable#View View Attributes}
92 * </p>
93 */
94@RemoteView
95public class Button extends TextView {
96    public Button(Context context) {
97        this(context, null);
98    }
99
100    public Button(Context context, AttributeSet attrs) {
101        this(context, attrs, com.android.internal.R.attr.buttonStyle);
102    }
103
104    public Button(Context context, AttributeSet attrs, int defStyleAttr) {
105        this(context, attrs, defStyleAttr, 0);
106    }
107
108    public Button(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
109        super(context, attrs, defStyleAttr, defStyleRes);
110    }
111
112    @Override
113    public CharSequence getAccessibilityClassName() {
114        return Button.class.getName();
115    }
116}
117