自定义TimePickerPreference

最近需要一个在让用户设置中设置时间的操作，发现网上的例子大多不能用了，于是自己写了一个供大家参考。

1.通过继承DialogPreference来实现点击该Preference后弹出带TimePicker的dialog。在构造方法中设定自定义的simpleSummaryProvider。

public class TimePickerPreference extends DialogPreference {
    private String mText;
    @Nullable
    private OnBindTimePickerListener mOnBindTimePickerListener;

    public TimePickerPreference(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        setSummaryProvider(SimpleSummaryProvider.getInstance());
        setDialogLayoutResource(R.layout.time_picker_dialog);
    }

    public TimePickerPreference(Context context, AttributeSet attrs, int defStyleAttr) {
        this(context, attrs, defStyleAttr, 0);
    }

    @SuppressLint("RestrictedApi")
    public TimePickerPreference(Context context, AttributeSet attrs) {
        this(context, attrs, TypedArrayUtils.getAttr(context, R.attr.dialogPreferenceStyle,
                android.R.attr.dialogPreferenceStyle));
    }

    public TimePickerPreference(Context context) {
        this(context, null);
    }

    public String getText() {
        return mText;
    }

    @Override
    public boolean shouldDisableDependents() {
        return TextUtils.isEmpty(mText) || super.shouldDisableDependents();
    }
    public void setText(String text) {
        final boolean wasBlocking = shouldDisableDependents();

        mText = text;

        persistString(text);

        final boolean isBlocking = shouldDisableDependents();
        if (isBlocking != wasBlocking) {
            notifyDependencyChange(isBlocking);
        }

        notifyChanged();
    }

    @Override
    protected Object onGetDefaultValue(TypedArray a, int index) {
        return a.getString(index);
    }

    @Override
    protected void onSetInitialValue(Object defaultValue) {
        setText(getPersistedString((String) defaultValue));
    }

    public void setOnBindTimePickerListener(@Nullable OnBindTimePickerListener onBindTimePickerListener) {
        mOnBindTimePickerListener = onBindTimePickerListener;
    }


    @Nullable
    OnBindTimePickerListener getOnBindTimePickerListener() {
        return mOnBindTimePickerListener;
    }

    public interface OnBindTimePickerListener {
        void onBindTimePicker(@NonNull TimePicker timePicker);
    }

    public static final class SimpleSummaryProvider implements SummaryProvider<TimePickerPreference> {

        private static SimpleSummaryProvider sSimpleSummaryProvider;

        private SimpleSummaryProvider() {}

        public static SimpleSummaryProvider getInstance() {
            if (sSimpleSummaryProvider == null) {
                sSimpleSummaryProvider = new SimpleSummaryProvider();
            }
            return sSimpleSummaryProvider;
        }

        @SuppressLint("PrivateResource")
        @Override
        public CharSequence provideSummary(TimePickerPreference preference) {
            if (TextUtils.isEmpty(preference.getText())) {
                return (preference.getContext().getString(R.string.not_set));
            } else {
                return preference.getText();
            }
        }
    }

}

2.还需配套写一个继承PreferenceDialogFragmentCompat的类来负责弹出的对话框的逻辑。

public class DialogPrefFragCompat extends PreferenceDialogFragmentCompat {
    private TimePicker mTimePicker;
    private CharSequence mText;

    public static DialogPrefFragCompat newInstance(String key) {
        final DialogPrefFragCompat fragment = new DialogPrefFragCompat();
        final Bundle bundle = new Bundle(1);
        bundle.putString(ARG_KEY, key);
        fragment.setArguments(bundle);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (savedInstanceState == null) {
            mText = getTimePickerPreference().getText();
            if(TextUtils.isEmpty(mText))
                mText=getContext().getText(R.string.default_remind_time);
        }
    }

    private TimePickerPreference getTimePickerPreference() {
        return (TimePickerPreference) getPreference();
    }

    @Override
    protected void onBindDialogView(View view) {
        super.onBindDialogView(view);

        mTimePicker = view.findViewById(R.id.time_picker);

        if (mTimePicker == null) {
            throw new IllegalStateException("Dialog view must contain an TimePicker with id" +
                    " @android:id/time_picker");
        }
        String[] hourAndMinute= mText.toString().split(":");
        int hour = Integer.parseInt(hourAndMinute[0]);
        int minute = Integer.parseInt(hourAndMinute[1]);
        mTimePicker.setCurrentHour(hour);
        mTimePicker.setCurrentMinute(minute);
        if (getTimePickerPreference().getOnBindTimePickerListener() != null) {
            getTimePickerPreference().getOnBindTimePickerListener().onBindTimePicker(mTimePicker);
        }
    }

    @Override
    public void onDialogClosed(boolean positiveResult) {
        if (positiveResult) {
            int hour = mTimePicker.getCurrentHour();
            int minute = mTimePicker.getCurrentMinute();
            String value = String.format("%02d:%02d",hour,minute);
            Toast.makeText(getContext(), value, Toast.LENGTH_SHORT).show();
            final TimePickerPreference preference = getTimePickerPreference();
            if (preference.callChangeListener(value)) {
                preference.setText(value);
            }
        }
    }

}

3.除此之外还需重写fragment页面的onDisplayPreferenceDialog方法来调用之前的PreferenceDialogFragmentCompat子类来生成dialog。

public class SettingsFragment extends PreferenceFragmentCompat{

    ...


    @Override
    public void onDisplayPreferenceDialog(Preference preference) {
        if (preference instanceof TimePickerPreference) {
            DialogFragment dialogFragment = DialogPrefFragCompat.newInstance(preference.getKey());
            dialogFragment.setTargetFragment(this, 0);
            dialogFragment.show(getParentFragmentManager(), null);//getFragmentManager()
        } else super.onDisplayPreferenceDialog(preference);
    }

    ...

}

4.布局参考

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/radial_time_picker"
    android:gravity="center"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">
    <TimePicker
        android:id="@+id/time_picker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:timePickerMode="spinner"/>
</LinearLayout>