private EditText result = (EditText) findViewById(R.id.editText1);
final String[] dropdownList ={"a123", "b456"};
public void onCreate(...) {
...
alert();
}
private void alert() {
new AlertDialog.Builder(this)
.setTitle("select")
.setSingleChoiceItems(dropdownList, checkedItem, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
result.setHint("some tips");
}
)}.show()
EditText 结果在 layout.xml 中已经有提示,但我想更改提示
EditText 结果,但是上面的代码抛出了 NullPointerException,这是什么问题?
编辑:
public class AAA extends Activity {
private EditText result;
private String[] dropdownList = {"A123", "A456"};
private int checkedItem = 0;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
result = (EditText) findViewById(R.id.editText1);
alert();
}
private void alert() {
new AlertDialog.Builder(this)
.setTitle("select")
.setSingleChoiceItems(dropdownList, checkedItem, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
result.setHint("some tips");
}
}).show();
}
}