无法终生了解我在做什么错。当我按我的按钮时，应用程序崩溃。如果有人可以帮助解决这个问题，您将感到惊讶。我需要停止该操作，以便可以测试其功能。我的，如果您发现我的代码有其他问题，或者有更好的方法，请随时纠正我。始终欢迎建设性反馈。
这些是它应该具有的所有功能。 https://youtu.be/qAXK2RxIh_s
这是我的代码：
public class MainActivity extends AppCompatActivity {
RadioGroup radioGroup;
RadioButton radioButton;
TextView selected_button;
TextView problem;
TextView correct_answer;
EditText user_answer;
TextView support;
int counter = 0;
int high = 0;
int low = 99;
int count= 0;
public int randGen(int low, int high) {
return (int) Math.round(Math.random() * (high - low)) + low;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
radioGroup = findViewById(R.id.radioGroup);
selected_button = findViewById(R.id.selection);
problem = findViewById(R.id.equation);
user_answer = findViewById(R.id.solution);
correct_answer = findViewById(R.id.answer_check);
support = findViewById(R.id.encouragement);
final Button buttonChecked = findViewById(R.id.button_check);
Button buttonProblem = findViewById(R.id.button_problem);
buttonProblem.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//boolean checked = ((RadioButton) view).isChecked();
//Timer
new CountDownTimer(30000,100){
public void onTick(long millisUnitilFinished){
support.setText(String.valueOf(counter));
}
public void onFinish(){
}
}.start();
int radioId = radioGroup.getCheckedRadioButtonId();
radioButton = findViewById(radioId);
user_answer.setText(" ");
//Addition method
if (radioId == R.id.add){
int num1;
int num2;
int sum;
num1 = randGen(0,99);
num2 = randGen(0,99);
problem.setText(num1 + '+' + num2 + '=');
sum = num1 + num2;
correct_answer.setText(sum);
support.setText(" ");
}
//Subtraction method
if (radioId == R.id.sub){
int num1;
int num2;
int diff;
num1 = randGen(0,99);
num2 = randGen(0,99);
problem.setText(num1 + '+' + num2 + '=');
diff = num1 - num2;
correct_answer.setText(diff);
support.setText(" ");
}
//Product method
if (radioId == R.id.prod){
int num1;
int num2;
int product;
num1 = randGen(0,99);
num2 = randGen(0,99);
problem.setText(num1 + '+' + num2 + '=');
product = num1 * num2;
correct_answer.setText(product);
support.setText(" ");
}
//Division Method
//Should only give problems whose remainder is zero.
if (radioId == R.id.div){
int num1;
int num2;
int division;
num1 = randGen(0,99);
num2 = randGen(0,99);
problem.setText(num1 + '+' + num2 + '=');
division = num1 / num2;
correct_answer.setText(division);
support.setText(" ");
}
}
});
buttonChecked.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//correct answer
if(user_answer == (EditText) correct_answer){
support.setText("Keep up the good work!");
buttonChecked.setEnabled(false);
}
//incorrect answer number 2
else if(count == 1){
buttonChecked.setEnabled(false);
support.setText("This is the correct answer" + correct_answer + "You suck!");
count--;
}
//incorrect answer number 1
else if(user_answer != correct_answer){
support.setText("I guess you can try one more time.");
count++;
}
//If no answer is typed but button is pressed.
if(user_answer.length()==0){
support.setText("ANSWER THE QUESTION!!");
}
}
});
}
//Message that lets user know what operation they have selected
public void checkButton(View v){
int radioId = radioGroup.getCheckedRadioButtonId();
radioButton = findViewById(radioId);
Toast.makeText(this, "You've selected: " + radioButton.getText(), Toast.LENGTH_SHORT).show();
}
}
这是我的xml：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="Pick an Arithmetic Operation"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<RadioGroup
android:id="@+id/radioGroup"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginTop="49dp"
android:orientation="horizontal"
android:layout_centerHorizontal="true">
<RadioButton
android:id="@+id/add"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="+"
android:layout_weight="1"
android:textAlignment="center"/>
<RadioButton
android:id="@+id/sub"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="-"
android:textAlignment="center"/>
<RadioButton
android:id="@+id/prod"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="x"
android:textAlignment="center"/>
<RadioButton
android:id="@+id/div"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="/"
android:textAlignment="center"/>
</RadioGroup>
<TextView
android:id="@+id/selection"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/button_problem"
android:layout_centerHorizontal="true"
android:layout_marginBottom="-123dp"
android:text="You've selected: "
android:textSize="25sp"
android:visibility="invisible" />
<Button
android:id="@+id/button_problem"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginTop="123dp"
android:text="GIVE ME A PROBLEM"
tools:layout_editor_absoluteX="135dp"
tools:layout_editor_absoluteY="32dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="Type your answer below"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/button_check"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="142dp"
android:text="CHECK MY ANSWER"
tools:layout_editor_absoluteX="202dp"
tools:layout_editor_absoluteY="37dp" />
<EditText
android:id="@+id/solution"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="217dp"
android:ems="10"
android:inputType="textPersonName" />
<TextView
android:id="@+id/equation"
android:layout_width="170dp"
android:layout_height="52dp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="193dp"
android:text="TextView"
android:visibility="invisible" />
<TextView
android:id="@+id/answer_check"
android:layout_width="200dp"
android:layout_height="65dp"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="28dp"
android:text="TextView"
android:visibility="invisible" />
<TextView
android:id="@+id/encouragement"
android:layout_width="156dp"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="108dp"
android:text="TextView"
android:visibility="invisible" />
</RelativeLayout>
答案 0 :(得分：0)
在处理“ buttonChecked” onClick事件时，类型转换无效。
if(user_answer == (TextView) correct_answer){ //your code has EditText
support.setText("Keep up the good work!");
buttonChecked.setEnabled(false);
}
“ correct_answer”对象的获取方式为
correct_answer = findViewById(R.id.answer_check);
被声明为“ TextView”。
<TextView
android:id="@+id/answer_check"
android:layout_width="200dp"
android:layout_height="65dp"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="28dp"
android:text="TextView"
android:visibility="invisible" />