我希望能够让用户选择选项,并希望在对话框中提供一些单选按钮。我已经在 OnCreate 部分声明了这样的单选按钮
@Override
protected Dialog onCreateDialog(int id) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
if (id > 0)
{
LayoutInflater layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
final View layout = layoutInflater.inflate(R.layout.lectsort_dialog, (ViewGroup) findViewById(R.id.lect_sort));
builder.setView(layout);
// Now configure the AlertDialog
builder.setTitle(R.string.exsort_title);
radio_date = (RadioButton) findViewById(R.id.RBdate);
radio_loctn = (RadioButton) findViewById(R.id.RBloctn);
radio_stream = (RadioButton) findViewById(R.id.RBstream);
radio_date.setOnClickListener(radio_listener);
radio_loctn.setOnClickListener(radio_listener);
radio_stream.setOnClickListener(radio_listener);
builder.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface arg0, int arg1) {
}
radio_listener 过程是这样声明的
RadioButton.OnClickListener radio_listener =
new RadioButton.OnClickListener()
{
@Override
public void onClick(View v) {
// Perform action on clicks
RadioButton rb = (RadioButton) v;
Toast.makeText(LecturesActivity.this, rb.getText(), Toast.LENGTH_SHORT).show();
}
};
但是,当调用对话框时,我在此行收到 Null 异常错误
radio_date.setOnClickListener(radio_listener);
我究竟做错了什么?