public class MainActivity extends Activity {
EditText number1, number2;
String number_1, number_2;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
number1 = (EditText) findViewById(R.id.number1);
number2 = (EditText) findViewById(R.id.number2);
number_1 = number1.getText().toString();
number_2 = number2.getText().toString();
爲什麼number_1
有一個空值。爲什麼在OnCreate方法中EditText轉換爲字符串不成立
onCreate()在創建Activity時被調用......那時沒有文本被設置爲EditText這就是爲什麼它返回空的String ..爲此你需要一個按鈕並寫入監聽器和得到的價值.. –
@ kalyanpvs謝謝你的解釋.... – user3237300
你*期待*看到什麼? – Simon