我的主要活动设置并开始一个对话框片段供用户与之交互。该对话框显示几个单选按钮可供选择，完成后可以取消或接受选择。主要活动使用接口在对话框片段被解除后检查事件，然后根据对话框片段中存在的相同变量更改局部变量。这对我来说似乎是多余的，那么有更好的方法来实现这种沟通吗？看看主要活动中的NOTI_TIMER。
主要活动：
public void dialogSetup(){
RadioButtonDialog dialog = new RadioButtonDialog();
dialog.show(getFragmentManager(), "Radio Button Dialog");
}
@Override
public void onDialogPositiveClick(DialogFragment dialog) {
NOTI_TIMER = RadioButtonDialog.getNOTI();
startAlarm();
}
@Override
public void onDialogNegativeClick(DialogFragment dialog) {
log("in onDialogNegativeClick");
}
对话片段：
public class RadioButtonDialog extends DialogFragment{
public String TAG = "RadioButtonDialog";
public static long NOTI_TIMER = 0;
RadioGroup mRadioGroup;
Button timerChoice;
/* The activity that creates an instance of this dialog fragment must
* implement this interface in order to receive event callbacks.
* Each method passes the DialogFragment in case the host needs to query it. */
public interface RadioButtonDialogListener {
public void onDialogPositiveClick(DialogFragment dialog);
public void onDialogNegativeClick(DialogFragment dialog);
}
// Use this instance of the interface to deliver action events
RadioButtonDialogListener mListener;
// Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// Verify that the host activity implements the callback interface
try {
// Instantiate the NoticeDialogListener so we can send events to the host
mListener = (RadioButtonDialogListener) activity;
} catch (ClassCastException e) {
// The activity doesn't implement the interface, throw exception
throw new ClassCastException(activity.toString()
+ " must implement NoticeDialogListener");
}
}
@Override
public Dialog onCreateDialog(Bundle SavedInstanceState){
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.timer_choice_layout, null);
mRadioGroup = (RadioGroup) view.findViewById(R.id.radioGroup1);
builder.setView(view);
builder.setTitle("Choose Selfie Timer Duration");
//timerChoice = (Button)view.findViewById(R.id.button1);
builder.setNegativeButton(R.string.delete_cancel, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Log.i(MainActivity.TAG, "User pressed 'Cancel'.");
mListener.onDialogNegativeClick(RadioButtonDialog.this);
}
});
builder.setPositiveButton(R.string.timer_btn_confirm, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
switch (mRadioGroup.getCheckedRadioButtonId()){
case R.id.radioButton1:
NOTI_TIMER = 10800000;
Toast.makeText(getActivity(), R.string.three_hours, Toast.LENGTH_LONG).show();
break;
case R.id.radioButton2:
Toast.makeText(getActivity(), R.string.six_hours, Toast.LENGTH_LONG).show();
NOTI_TIMER = 21600000;
break;
case R.id.radioButton3:
Toast.makeText(getActivity(), R.string.nine_hours, Toast.LENGTH_LONG).show();
NOTI_TIMER = 32400000;
break;
case R.id.radioButton4:
Toast.makeText(getActivity(), R.string.twelve_hours, Toast.LENGTH_LONG).show();
NOTI_TIMER = 43200000;
break;
case R.id.radioButton5:
Toast.makeText(getActivity(), R.string.twentyfour_hours, Toast.LENGTH_LONG).show();
NOTI_TIMER = 86400000;
break;
}
mListener.onDialogPositiveClick(RadioButtonDialog.this);
}
});
Dialog dialog = builder.create();
return(dialog);
}
public static long getNOTI() {
return NOTI_TIMER;
}
}