/* * 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; /** *

* A radio button is a two-states button that can be either checked or * unchecked. When the radio button is unchecked, the user can press or click it * to check it. However, contrary to a {@link android.widget.CheckBox}, a radio * button cannot be unchecked by the user once checked. *

* *

* Radio buttons are normally used together in a * {@link android.widget.RadioGroup}. When several radio buttons live inside * a radio group, checking one radio button unchecks all the others.

*

* *

See the Form Stuff * tutorial.

* *

XML attributes

*

* See {@link android.R.styleable#CompoundButton CompoundButton Attributes}, * {@link android.R.styleable#Button Button Attributes}, * {@link android.R.styleable#TextView TextView Attributes}, * {@link android.R.styleable#View View Attributes} *

*/ public class RadioButton extends CompoundButton { public RadioButton(Context context) { this(context, null); } public RadioButton(Context context, AttributeSet attrs) { this(context, attrs, com.android.internal.R.attr.radioButtonStyle); } public RadioButton(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } /** * {@inheritDoc} *

* If the radio button is already checked, this method will not toggle the radio button. */ @Override public void toggle() { // we override to prevent toggle when the radio is already // checked (as opposed to check boxes widgets) if (!isChecked()) { super.toggle(); } } }