/*
* 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.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityNodeInfo;
import com.android.internal.R;
/**
* <p>单选按钮是有选中和未选中两种状态的按钮.当其未选中时,用户可以通过按下或点击来选中它.
* 然而,与 {@link android.widget.CheckBox} 不同,用户一旦选中了单选按钮就不能够取消选中.</p>
*
* <p>单选按钮通常与 {@link android.widget.RadioGroup} 同时使用.
* 当多个单选按钮属于同一个单选按钮组时,选中其中一个的同时将取消其它单选按钮的选中状态.</p>
*
* <p>See the <a href="{@docRoot}guide/topics/ui/controls/radiobutton.html">Radio Buttons</a>
* guide.</p>
*
* <p><strong>XML attributes</strong></p>
* <p>
* 参见 {@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}.
* </p>
* @author translate by 农民伯伯
* @author convert by cnmahj
*/
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}
* <p>如果单选按钮已经选中,这个方法将不改变选中状态.</p>
*/
@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();
}
}
@Override
public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
super.onInitializeAccessibilityEvent(event);
event.setClassName(RadioButton.class.getName());
}
@Override
public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfo(info);
info.setClassName(RadioButton.class.getName());
}
}