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/*
* Copyright (C) 2006 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 android.widget;
import android.content.Context;
import android.util.AttributeSet;
import android.widget.RemoteViews.RemoteView;
/**
* Represents a push-button widget. Push-buttons can be
* pressed, or clicked, by the user to perform an action.
* A typical use of a push-button in an activity would be the following:
*
*
*
* public class MyActivity extends Activity {
* protected void onCreate(Bundle icicle) {
* super.onCreate(icicle);
*
* setContentView(R.layout.content_layout_id);
*
* final Button button = (Button) findViewById(R.id.button_id);
* button.setOnClickListener(new View.OnClickListener() {
* public void onClick(View v) {
* // Perform action on click
* }
* });
* }
* }
*
* However, instead of applying an {@link android.view.View.OnClickListener OnClickListener} to
* the button in your activity, you can assign a method to your button in the XML layout,
* using the {@link android.R.attr#onClick android:onClick} attribute. For example:
*
*
* <Button
* android:layout_height="wrap_content"
* android:layout_width="wrap_content"
* android:text="@string/self_destruct"
* android:onClick="selfDestruct" />
*
* Now, when a user clicks the button, the Android system calls the activity's {@code
* selfDestruct(View)} method. In order for this to work, the method must be public and accept
* a {@link android.view.View} as its only parameter. For example:
*
*
* public void selfDestruct(View view) {
* // Kabloey
* }
*
* The {@link android.view.View} passed into the method is a reference to the widget
* that was clicked.
*
* Button style
*
* Every Button is styled using the system's default button background, which is often different
* from one device to another and from one version of the platform to another. If you're not
* satisfied with the default button style and want to customize it to match the design of your
* application, then you can replace the button's background image with a state list drawable.
* A state list drawable is a drawable resource defined in XML that changes its image based on
* the current state of the button. Once you've defined a state list drawable in XML, you can apply
* it to your Button with the {@link android.R.attr#background android:background}
* attribute. For more information and an example, see State List
* Drawable.
*
* See the Buttons
* guide.
*
* XML attributes
*
* See {@link android.R.styleable#Button Button Attributes},
* {@link android.R.styleable#TextView TextView Attributes},
* {@link android.R.styleable#View View Attributes}
*
*/
@RemoteView
public class Button extends TextView {
public Button(Context context) {
this(context, null);
}
public Button(Context context, AttributeSet attrs) {
this(context, attrs, com.android.internal.R.attr.buttonStyle);
}
public Button(Context context, AttributeSet attrs, int defStyleAttr) {
this(context, attrs, defStyleAttr, 0);
}
public Button(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
}
@Override
public CharSequence getAccessibilityClassName() {
return Button.class.getName();
}
}