我正在尝试为对话框中的按钮设置 onclicklistener。但是,当我的对话框加载时,它崩溃了,并在 行上显示
.我有以下对话框:尝试在空对象引用上调用虚拟方法“android.view.View android.view.View.findViewById(int)”
>date = (Button) v.findViewById(R.id.DateButton);
public class EventsDialog extends DialogFragment {
private Button date;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.event_dialog, container, false);
date = (Button) v.findViewById(R.id.DateButton);
// set onclicklistener
date.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
OpenDate();
}
});
return v;
}
@Override
public Dialog onCreateDialog(Bundle savedInstanceState){
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
// Get the layout inflater
LayoutInflater inflater = getActivity().getLayoutInflater();
// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
builder.setView(inflater.inflate(R.layout.event_dialog, null));
return builder.create();
}
public void OpenDate() {
DatePickerFragment newFragment = new DatePickerFragment();
newFragment.show(getActivity().getSupportFragmentManager(), "datepicker");
}
}
布局:
android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="@dimen/mr_controller_volume_group_list_max_height"
android:layout_height="match_parent"
android:background="#dfdfdf"
android:orientation="vertical">
<TextView
android:id="@+id/eventsHeader"
android:layout_width="0dp"
android:layout_height="46dp"
android:background="@color/colorAccent"
android:text="Add a New Event!"
android:textAppearance="@style/TextAppearance.AppCompat.Display1"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:textColor="@android:color/white" />
<EditText
android:id="@+id/EventName"
android:layout_width="match_parent"
android:layout_height="46dp"
android:layout_marginEnd="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="7dp"
android:hint="Event Name"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/eventsHeader" />
<Button
android:id="@+id/DateButton"
android:layout_width="0dp"
android:layout_height="36dp"
android:layout_marginEnd="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="10dp"
android:text=""
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/EventName" />
<Button
android:id="@+id/TimeButton"
android:layout_width="0dp"
android:layout_height="35dp"
android:layout_marginEnd="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="10dp"
android:text=""
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/DateButton" />
<EditText
android:id="@+id/EventLocation"
android:layout_width="0dp"
android:layout_height="46dp"
android:layout_marginEnd="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="10dp"
android:hint="Location"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/TimeButton" />
<EditText
android:id="@+id/EventDetails"
android:layout_width="0dp"
android:layout_height="186dp"
android:layout_marginEnd="16dp"
android:layout_marginStart="16dp"
android:layout_marginTop="10dp"
android:ems="10"
android:hint="Details"
android:inputType="textMultiLine"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/EventLocation" />
<ImageButton
android:id="@+id/SaveButtonEvents"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginTop="10dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="@+id/EventDetails"
app:srcCompat="@android:drawable/ic_menu_save" />
</android.support.constraint.ConstraintLayout>
最佳答案
您正在膨胀
您的布局
两次。请在 onCreateDialog()
方法中对其进行充气,并执行如下操作并删除 onCreateView()
方法:
@NonNull
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
View view = getActivity().getLayoutInflater().inflate(R.layout.event_dialog, null,false);
builder.setView(view);
builder.setTitle("Your Title");
date = (Button) view.findViewById(R.id.DateButton);
// set onclicklistener
date.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
OpenDate();
}
});
return builder.create();
关于android - 尝试在 DialogFragment 中的按钮上设置 OnClickListener,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48220054/