android.widget.Button无法强制转换为android.widget.EditText

Mic*_*ael 6 android

开发我的第一个Android计算器应用程序,我成功通过意图传递答案来更新新活动中的TextView,但这需要用户点击返回执行另一个计算.我正在尝试使doCalculation按钮更新MainActivity中的简单TextView并获取错误:

06-22 11:08:17.318:E/AndroidRuntime(31328):引起:java.lang.ClassCastException:android.widget.Button无法强制转换为android.widget.EditText

这是我的代码:

/** Called when the user clicks the Calculate! button */
public void doCalculation(View view) {
    // Do something in response to button
    int answerInt;
    String answer;
    EditText numberOne = (EditText) findViewById(R.id.number1);
    EditText numberTwo = (EditText) findViewById(R.id.number2);
    int numberOnee = Integer.parseInt(numberOne.getText().toString());
    int numberTwoo = Integer.parseInt(numberTwo.getText().toString());
    answerInt = numberOnee * numberTwoo;
    answer = Integer.toString(answerInt);

    TextView homeAnswerView = (TextView) findViewById(R.id.homeAnswerView);
    homeAnswerView.setTextSize(40);
    homeAnswerView.setText(answer);
}
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作为参考,这里是成功启动新活动的代码:

// Called when the user clicks the Calculate! button
public void doCalculation(View view) {
    // Do something in response to button
    int answerInt;
    String answer;
    Intent intent = new Intent(this, DisplayCalculationActivity.class);
    EditText numberOne = (EditText) findViewById(R.id.number1);
    EditText numberTwo = (EditText) findViewById(R.id.number2);
    int numberOnee = Integer.parseInt(numberOne.getText().toString());
    int numberTwoo = Integer.parseInt(numberTwo.getText().toString());
    answerInt = numberOnee * numberTwoo;
    answer = Integer.toString(answerInt);
    intent.putExtra(EXTRA_MESSAGE, answer);
    startActivity(intent);
}
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UPDATE,XML供参考:

<EditText
    android:id="@+id/number2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/textView3"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="16dp"
    android:ems="10"
    android:inputType="number" />

<EditText
    android:id="@+id/number1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/textView1"
    android:layout_centerHorizontal="true"
    android:ems="10"
    android:inputType="number"
    android:singleLine="true" />

<Button
    android:id="@+id/calculateBtn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/number2"
    android:layout_alignRight="@+id/number2"
    android:layout_below="@+id/number2"
    android:layout_marginTop="14dp"
    android:onClick="doCalculation"
    android:text="Calculate!" />
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谢谢你的帮助,迈克尔

Ole*_*siy 13

似乎R.id.number1或R.id.number2是一个Button.检查您的XML并确保它是EditText.

编辑:原始答案不起作用,但清理项目解决了问题.

  • 再试一次:清理你的项目 (4认同)