无法从单选按钮中获取价值

Question

我正在尝试从 RadioButton 中获取由数组字符串创建的值 我正在使用 OClickListener() 从 RadioButton 获取值，但显示错误
" java.lang.ClassCastException: android.widget.Button 无法转换为 android.widget.RadioButton "

这是我的代码，请检查

for(int i =0; i<ab.length;i++)
{
RadioButton radioButtonView = new RadioButton(this);
radioButtonView.setText(ab[i]);
radioGroup.addView(radioButtonView, p);
}
       
Button btnDisplay = (Button) findViewById(R.id.button1);
btnDisplay.setOnClickListener(new OnClickListener() {

	@Override
	public void onClick(View v)
    {
	// TODO Auto-generated method stub
	// get selected radio button from radioGroup
	int selectedId = radioGroup.getCheckedRadioButtonId();
	// find the radiobutton by returned id
    String s = ((RadioButton) v ).getText().toString();
	Toast.makeText(Radio_Button.this, "This is: " + s,Toast.LENGTH_LONG).show();
  }

而 LogCat 是

   
 FATAL EXCEPTION: main
 Process: com.example.radiobuttondynamic, PID: 4741
 java.lang.ClassCastException: android.widget.Button cannot be cast to android.widget.RadioButton
 	at com.example.radiobuttondynamic.Radio_Button$1.onClick(Radio_Button.java:64)
 	at android.view.View.performClick(View.java:4438)
 	at android.view.View$PerformClick.run(View.java:18422)
 	at android.os.Handler.handleCallback(Handler.java:733)
 	at android.os.Handler.dispatchMessage(Handler.java:95)
 	at android.os.Looper.loop(Looper.java:136)
 	at android.app.ActivityThread.main(ActivityThread.java:5017)
 	at java.lang.reflect.Method.invokeNative(Native Method)
 	at java.lang.reflect.Method.invoke(Method.java:515)
 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
 	at dalvik.system.NativeStart.main(Native Method)

请提出改正建议

谢谢 谢谢

Answer 1

v 是 Button，您在这一行将其转换为 RadioButton：

String s = ((RadioButton) v ).getText().toString();

试试这个：

如果您以编程方式添加了radioButton，您可以将setID 添加到radioButtons：

for(int i =0; i<ab.length;i++)
{
RadioButton radioButtonView = new RadioButton(this);
radioButtonView.setText(ab[i]);
radioButtonView.setID(i);
radioGroup.addView(radioButtonView, p);
}

然后

 String s = ((RadioButton) findViewById(yourRadioButtonID) ).getText().toString();

Answer 2

您为什么要尝试将按钮转换为单选按钮？ 无论如何，如果您想获取所选单选按钮的文本，请执行以下操作

btnDisplay.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v)
{

  RadioButton selectedButton=   (RadioButton)findViewById(radioGroup.getCheckedRadioButtonId());  //you will get the selected radiobutton here

 String s=selectedButton..getText().toString();
 Toast.makeText(Radio_Button.this, "This is: " + s,Toast.LENGTH_LONG).show();

}

Answer 3

使用这个：

String s = radioButtonView.getText().toString();

代替：

String s = ((RadioButton) v ).getText().toString();

Answer 4

我正在编写 onclick 功能。

public void onClick(View v)
 {

  int selectedId = radioGroup.getCheckedRadioButtonId();
    if(selectedId !=-1)
     {    
        View radioButton = radioGroup.findViewById(selectedId );
        int radioId = radioGroup.indexOfChild(radioButton);
        RadioButton btn = (RadioButton) radioGroup.getChildAt(radioId);
        String selection = (String) btn.getText();
    Toast.makeText(Radio_Button.this, "This is: " + s,Toast.LENGTH_LONG).show();
    }   
 }

试试这个，如果你有任何问题，请评论。