java - DialogFragment中的Android findViewById

Question

我正在尝试开发一个日期选择器，在设置时设置 TextView 的值。

但我无法从处理日期选择器的 DialogFragment 中选择电视。

我尝试了 getView 但应用程序在特定点崩溃。

这是我的代码:

@SuppressLint("NewApi")
public class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

    TextView mTextView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

                // R.layout.my_layout - that's the layout where your textview is placed
        View view = inflater.inflate(R.layout.activity_register_screen, container, false);
        mTextView = (TextView) view.findViewById(R.id.tvDate);
        // you can use your textview.
        return view;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        int year = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);

        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    public void onDateSet(DatePicker view, int year, int month, int day) {
        int syear = year;
        int smonth = month;
        int sday = day;
        // set selected date into textview
        mTextView.setText(new StringBuilder().append(smonth + 1)
           .append("-").append(sday).append("-").append(syear)
           .append(" "));
    }
}

更新了新代码和以下错误:

04-15 09:45:30.880: E/AndroidRuntime(23016): FATAL EXCEPTION: main
04-15 09:45:30.880: E/AndroidRuntime(23016): android.util.AndroidRuntimeException: requestFeature() must be called before adding content
04-15 09:45:30.880: E/AndroidRuntime(23016):    at com.android.internal.policy.impl.PhoneWindow.requestFeature(PhoneWindow.java:239)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at com.android.internal.app.AlertController.installContent(AlertController.java:236)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.AlertDialog.onCreate(AlertDialog.java:336)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.Dialog.dispatchOnCreate(Dialog.java:353)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.Dialog.show(Dialog.java:257)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.DialogFragment.onStart(DialogFragment.java:490)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.Fragment.performStart(Fragment.java:1537)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:866)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1036)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.BackStackRecord.run(BackStackRecord.java:622)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1386)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.FragmentManagerImpl$1.run(FragmentManager.java:430)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.os.Handler.handleCallback(Handler.java:605)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.os.Handler.dispatchMessage(Handler.java:92)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.os.Looper.loop(Looper.java:137)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at android.app.ActivityThread.main(ActivityThread.java:4517)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at java.lang.reflect.Method.invokeNative(Native Method)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at java.lang.reflect.Method.invoke(Method.java:511)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760)
04-15 09:45:30.880: E/AndroidRuntime(23016):    at dalvik.system.NativeStart.main(Native Method)

已解决

Answer 1

要在 Fragment/Fragment 对话框中获取特定 View ，您应该使用 onCreateView()。这是一个如何做到这一点的示例:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    // R.layout.my_layout - that's the layout where your textview is placed
    View view = inflater.inflate(R.layout.my_layout, container, false);
    TextView mTextView = (TextView) view.findViewById(R.id.colors);
    // you can use your textview.
    return view;
}

首先检查 onCreateDialog() 是否在 onCreateView() 之前调用，如果是这样，请尝试使用类似这样的方法:

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    // Use the Builder class for convenient dialog construction
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    LayoutInflater inflater = getActivity().getLayoutInflater();
    View view = inflater.inflate(R.layout. activity_register_screen, null);
    builder.setView(view);
    // Create the AlertDialog object and return it
    return builder.create();
}