Radio Buttons
By default, radio buttons appear as a round icon, and you can put some descriptive text next to the icon. Normally the RadioButton component needs to be used together with the RadioGroup component to form a radio button group. RadioGroup is a container that can hold multiple RadioButtons.
<LinearLayout
android:layout_width="match_parent"
android:layout_height="60dp"
android:orientation="horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:text="选择性别："
android:textSize="25sp"
android:gravity="center"
android:textColor="@color/black"/>
<RadioGroup
android:id="@+id/radioGroup"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:gravity="center">
<RadioButton
android:id="@+id/radio_man"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="男"
android:textColor="@color/black"
android:textSize="25sp"
android:checked="true"/>
<RadioButton
android:id="@+id/radio_female"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="女"
android:textColor="@color/black"
android:layout_marginLeft="100dp"
android:textSize="25sp"/>
</RadioGroup>
</LinearLayout>
<Button
android:id="@+id/bt_submit"
android:layout_width="100dp"
android:layout_height="50dp"
android:text="提交"
android:textSize="20sp"
android:layout_marginTop="10dp"
android:layout_gravity="center"/>The layout effect shows:
The android:checked attribute of the RadioButton component is used to specify the selected state. When android:checked="true", it means selected; when android:checked="false", it means unchecked.
There are three ways to get the selected value:
The first is to set an event listener setOnCheckChangeListener for RadioButton.
public class MainActivity extends AppCompatActivity {
RadioGroup radioGroup;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化控件
initView();
//点击事件
clickEvent();
}
private void initView() {
radioGroup = findViewById(R.id.radioGroup);
}
private void clickEvent() {
//给RadioGroup绑定监视器
radioGroup.setOnCheckedChangeListener(new MyRadioButtonListener());
}
//单选按钮监听
private class MyRadioButtonListener implements RadioGroup.OnCheckedChangeListener {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
RadioButton r = (RadioButton) findViewById(checkedId);//获取被选中的Id
Log.i("单选按钮监听", "选择性别为：" + r.getText().toString());
}
}
}Radio button listening log effect:
The second method is to obtain the value of the selected radio button by clicking other buttons.
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
RadioGroup radioGroup;
//提交
Button bt_submit;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化控件
initView();
//点击事件
clickEvent();
}
private void initView() {
radioGroup = findViewById(R.id.radioGroup);
bt_submit = findViewById(R.id.bt_submit);
}
private void clickEvent() {
//提交
bt_submit.setOnClickListener(this);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.bt_submit:
for (int i = 0; i < radioGroup.getChildCount(); i++) {
RadioButton r = (RadioButton) radioGroup.getChildAt(i);
if (r.isChecked()) {
Log.i("单击其他按钮时获取", "选择性别为：" + r.getText());
}
}
break;
}
}
}Display of the log effect of determining when other buttons are clicked to obtain the value of the selected radio button:
The third method is to determine which radio button's ID the clicked ID is, and obtain the value through the ID.
public class MainActivity extends AppCompatActivity {
RadioGroup radioGroup;
//男
RadioButton radio_man;
//女
RadioButton radio_female;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化控件
initView();
//点击事件
clickEvent();
}
private void initView() {
radioGroup = findViewById(R.id.radioGroup);
radio_man = findViewById(R.id.radio_man);
radio_female = findViewById(R.id.radio_female);
}
private void clickEvent() {
//给RadioGroup绑定监视器
radioGroup.setOnCheckedChangeListener(new MyRadioButtonListener());
}
//单选按钮监听
private class MyRadioButtonListener implements RadioGroup.OnCheckedChangeListener {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
// 选中状态改变时被触发
switch (checkedId) {
case R.id.radio_female:
// 当用户选择女性时
Log.i("判断点击Id的单选按钮", "选择性别为：" + radio_female.getText().toString());
break;
case R.id.radio_man:
// 当用户选择男性时
Log.i("判断点击Id的单选按钮", "选择性别为："+radio_man.getText().toString());
break;
}
}
}
}Determine the clicked radio button log effect display:
