Java 如何在按下按钮时检查选中的单选按钮
当我点击执行一个方法的按钮时,我得到了这个错误Java 如何在按下按钮时检查选中的单选按钮,java,android,Java,Android,当我点击执行一个方法的按钮时,我得到了这个错误 Process: com.example.myapplication, PID: 7757 java.lang.IllegalStateException: Could not execute method for android:onClick at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInfla
Process: com.example.myapplication, PID: 7757
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:390)
at android.view.View.performClick(View.java:6304)
at android.view.View$PerformClick.run(View.java:24803)
at android.os.Handler.handleCallback(Handler.java:794)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:6635)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385)
at android.view.View.performClick(View.java:6304)
at android.view.View$PerformClick.run(View.java:24803)
at android.os.Handler.handleCallback(Handler.java:794)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:6635)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
Caused by: java.lang.ClassCastException: android.support.v7.widget.AppCompatButton cannot be cast to android.widget.RadioButton
at com.example.myapplication.MockTest.submitbtn(MockTest.java:66)
at java.lang.reflect.Method.invoke(Native Method)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385)
at android.view.View.performClick(View.java:6304)
at android.view.View$PerformClick.run(View.java:24803)
at android.os.Handler.handleCallback(Handler.java:794)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:6635)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
该方法由android调用:单击按钮时单击xml
这就是方法
public void submitbtn(View view)
{
boolean checked = ((RadioButton) view).isChecked();
switch (view.getId()) {
case R.id.q1r1: if (checked)
score++;
break;
case R.id.q2r4: if (checked)
score++;
break;
case R.id.q3r4: if (checked)
score++;
break;
case R.id.q4r2: if (checked)
score++;
break;
}
}
这是按钮的xml条目
<Button
android:id="@+id/submitbtn"
android:layout_width="100dp"
android:layout_height="65dp"
android:layout_marginStart="150dp"
android:layout_marginTop="10dp"
android:layout_marginEnd="150dp"
android:text="Submit"
android:onClick="submitbtn"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/q4r" />
我查看了错误,注意到它说这是因为radiobutton小部件无法转换为button小部件造成的,对吗?如果是的话,我该如何实现这一点。我试图做的只是在单击按钮后检查单选按钮的当前状态(已选中或未选中)。我以前的方法很有效,就是这个方法,但它是通过一个单选按钮调用的。我在radiobutton的xml文件上放了一个android:onClick。但这不起作用。找到了解决方案,显然我需要使用RadioGroup,而不是直接使用单选按钮,我所做的唯一更改是代码,在这里
public void submitbtn(View view)
{
RadioGroup q4r = findViewById(R.id.q4r);
//Checking which radio button is checked, if any, and then executing tasks
if(q1r.getCheckedRadioButtonId() == R.id.q1r1)
{
//execute tasks
}
else if(q1r.getCheckedRadioButtonId() == -1)
{
//Nothing
}
else
{
//execute tasks
}
}
您必须使用RadioGroup,因为您已经解决了它,我只能指出它崩溃的原因。此行
boolean checked=((RadioButton)视图).isChecked()代码>使其崩溃,因为视图
的类型是按钮
,而不是您试图将其强制转换到的RadioButton
。