Android 从选定的单选按钮获取值

我有一段代码与三个 RadioButton在一个 RadioGroup。我想设置一个 onCheckedListener，它将在 Toast中显示 RadioButton的值。然而，我目前所得到的并不奏效。如何获得 RadioButton的值并将其显示在 Toast中？这是我的暗号:

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.Toast;


public class MainActivity extends Activity {


RadioGroup rg;


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);


RadioGroup rg = (RadioGroup) findViewById(R.id.radioGroup1);
final String value =
((RadioButton)findViewById(rg.getCheckedRadioButtonId()))
.getText().toString();


rg.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(RadioGroup group, int checkedId) {
Toast.makeText(getBaseContext(), value, Toast.LENGTH_SHORT).show();
}
});
}
}

XML 文件:

<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >


<RadioGroup
android:id="@+id/radioGroup1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="152dp" >


<RadioButton
android:id="@+id/radio0"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Choose 1" />


<RadioButton
android:id="@+id/radio1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Choose 2" />


<RadioButton
android:id="@+id/radio2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Choose 3" />
</RadioGroup>
</RelativeLayout>
396209 次浏览
小开
最佳答案

测试正常，检查 这个

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;


public class MyAndroidAppActivity extends Activity {


private RadioGroup radioGroup;
private RadioButton radioButton;
private Button btnDisplay;


@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);


addListenerOnButton();


}


public void addListenerOnButton() {


radioGroup = (RadioGroup) findViewById(R.id.radio);
btnDisplay = (Button) findViewById(R.id.btnDisplay);


btnDisplay.setOnClickListener(new OnClickListener() {


@Override
public void onClick(View v) {


// get selected radio button from radioGroup
int selectedId = radioGroup.getCheckedRadioButtonId();


// find the radiobutton by returned id
radioButton = (RadioButton) findViewById(selectedId);


Toast.makeText(MyAndroidAppActivity.this,
radioButton.getText(), Toast.LENGTH_SHORT).show();


}


});


}
}

Xml

<RadioGroup
android:id="@+id/radio"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >


<RadioButton
android:id="@+id/radioMale"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/radio_male"
android:checked="true" />


<RadioButton
android:id="@+id/radioFemale"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/radio_female" />


</RadioGroup>
小开

在这种情况下，如果您想要对单选按钮的选择进行一些操作(不需要任何附加的 OK 按钮或其他东西) ，那么您的代码是可以的，只需更新很少。

public class MainActivity extends Activity {


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);


RadioGroup rg = (RadioGroup) findViewById(R.id.radioGroup1);


rg.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()
{
public void onCheckedChanged(RadioGroup group, int checkedId) {
switch(checkedId){
case R.id.radio0:
// do operations specific to this selection
break;
case R.id.radio1:
// do operations specific to this selection
break;
case R.id.radio2:
// do operations specific to this selection
break;
}
}
});
}
}
小开

当 RadioButtons 动态生成时，我也遇到过获取单选按钮 id 的问题。如果您尝试使用 RadioButton.setId()手动设置 ID，那么它似乎不起作用。对我有效的方法是使用 View.getChildAt()和 View.getParent()来迭代单选按钮并确定选中了哪一个。所有您需要的是首先通过 findViewById(R.id.myRadioGroup)获得 RadioGroup，然后遍历它的子节点。当您循环访问所处的按钮时，您将知道该按钮，并且您可以简单地使用 RadioButton.isChecked()来确定该按钮是否是被选中的按钮。

小开

只要使用 getCheckedRadioButtonId()函数来判断是否有检查，如果 -1是 return值，就可以避免显示吐司

小开 
radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId)
{
radioButton = (RadioButton) findViewById(checkedId);
Toast.makeText(getBaseContext(), radioButton.getText(), Toast.LENGTH_SHORT).show();
}
}
);
小开

对于任何以编程方式填充并希望获得索引的人来说，您可能会注意到，当您返回活动/片段并重新添加这些单选按钮时，checkedId 会发生变化。解决这个问题的一个方法是用索引设置一个标记:

    for(int i = 0; i < myNames.length; i++) {
rB = new RadioButton(getContext());
rB.setText(myNames[i]);
rB.setTag(i);
myRadioGroup.addView(rB,i);
}

然后在你的听众中:

    myRadioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
RadioButton radioButton = (RadioButton) group.findViewById(checkedId);
int mySelectedIndex = (int) radioButton.getTag();
}
});
小开 
int genid=gender.getCheckedRadioButtonId();
RadioButton radioButton = (RadioButton) findViewById(genid);
String gender=radioButton.getText().toString();

希望这个工作。您可以按照以上方式将输出转换为字符串。 性别是 RadioGroup 的标志。

小开

多亏了克里斯。

这是我的解决办法:

RadioGroup radgroup_opcionesEventos = null;




private static String[] arrayEventos = {
"Congestión", "Derrumbe", "Accidente"
};
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
radgroup_opcionesEventos = (RadioGroup)findViewById(R.id.rg_opciones_evento);
int i=0;//a.new.ln
for(String evento : arrayEventos) {
//RadioButton nuevoRadio = crearRadioButton(evento);//a.old.ln
RadioButton nuevoRadio = crearRadioButton(evento,i);//a.new.ln
radgroup_opcionesEventos.addView(nuevoRadio,i);
}


RadioButton primerRadio = (RadioButton) radgroup_opcionesEventos.getChildAt(0);
primerRadio.setChecked(true);
}


private RadioButton crearRadioButton(String evento, int n)
{
//RadioButton nuevoRadio = new RadioButton(this);//a.old.ln
RadioButton nuevoRadio = new RadioButton(getApplicationContext());//a.new.ln


LinearLayout.LayoutParams params = new RadioGroup.LayoutParams(
RadioGroup.LayoutParams.WRAP_CONTENT,
RadioGroup.LayoutParams.WRAP_CONTENT);
nuevoRadio.setLayoutParams(params);
nuevoRadio.setText(evento);
nuevoRadio.setTag(evento);
return nuevoRadio;
}




@Override
protected void onResume()
{
radgroup_opcionesEventos.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
RadioButton radioButton = (RadioButton) group.findViewById(checkedId);
//int mySelectedIndex = (int) radioButton.getTag();
String mySelectedIndex = radioButton.getTag().toString();
}
});
super.onResume();
}
小开 
Radiogroup rgteam;
String team;
rgteam.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
RadioButton rb= (RadioButton) findViewById(checkedId);
team = rb.getText().toString();
}
});
小开 
mRadioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, @IdRes int checkedId) {
RadioButton radioButton = (RadioButton)group.findViewById(checkedId);
}
});
小开

XML 中的 RadioGroup

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<RadioGroup
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Java"/>


</RadioGroup>
</RelativeLayout>

Activity _ main. xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="150dp"
android:layout_marginLeft="100dp"
android:textSize="18dp"
android:text="Select Your Course"
android:textStyle="bold"
android:id="@+id/txtView"/>
<RadioGroup
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:id="@+id/rdGroup"
android:layout_below="@+id/txtView">
<RadioButton
android:id="@+id/rdbJava"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10dp"
android:layout_marginLeft="100dp"
android:text="Java"
android:onClick="onRadioButtonClicked"/>
<RadioButton
android:id="@+id/rdbPython"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10dp"
android:layout_marginLeft="100dp"
android:text="Python"
android:onClick="onRadioButtonClicked"/>
<RadioButton
android:id="@+id/rdbAndroid"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10dp"
android:layout_marginLeft="100dp"
android:text="Android"
android:onClick="onRadioButtonClicked"/>
<RadioButton
android:id="@+id/rdbAngular"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="10dp"
android:layout_marginLeft="100dp"
android:text="AngularJS"
android:onClick="onRadioButtonClicked"/>
</RadioGroup>
<Button
android:id="@+id/getBtn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="100dp"
android:layout_below="@+id/rdGroup"
android:text="Get Course" />
</RelativeLayout>

MainActivity.java

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.Toast;


public class MainActivity extends AppCompatActivity {
RadioButton android, java, angular, python;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
android = (RadioButton)findViewById(R.id.rdbAndroid);
angular = (RadioButton)findViewById(R.id.rdbAngular);
java = (RadioButton)findViewById(R.id.rdbJava);
python = (RadioButton)findViewById(R.id.rdbPython);
Button btn = (Button)findViewById(R.id.getBtn);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String result = "Selected Course: ";
result+= (android.isChecked())?"Android":(angular.isChecked())?"AngularJS":(java.isChecked())?"Java":(python.isChecked())?"Python":"";
Toast.makeText(getApplicationContext(), result, Toast.LENGTH_SHORT).show();
}
});
}
public void onRadioButtonClicked(View view) {
boolean checked = ((RadioButton) view).isChecked();
String str="";
// Check which radio button was clicked
switch(view.getId()) {
case R.id.rdbAndroid:
if(checked)
str = "Android Selected";
break;
case R.id.rdbAngular:
if(checked)
str = "AngularJS Selected";
break;
case R.id.rdbJava:
if(checked)
str = "Java Selected";
break;
case R.id.rdbPython:
if(checked)
str = "Python Selected";
break;
}
Toast.makeText(getApplicationContext(), str, Toast.LENGTH_SHORT).show();
}
}

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