要使用开关等创建自定义首选项标头,您需要使用标头扩展 PreferenceActivity,如 Android 文档所述,然后覆盖 PreferenceActivity.setListAdapter 以创建您自己的列表适配器,从而创建自定义视图。我用实际 android 设置活动中的代码制作了一个 pastebin 来帮助你。 http://pastebin.com/RhSndGCQ
@Override
public void onBuildHeaders(List<Header> headers) {
loadHeadersFromResource(R.xml.settings_headers, headers);
updateHeaderList(headers);
}
@Override
public void setListAdapter(ListAdapter adapter) {
if (adapter == null) {
super.setListAdapter(null);
} else {
super.setListAdapter(new HeaderAdapter(this, getHeaders(), mAuthenticatorHelper));
}
}
private static class HeaderAdapter extends ArrayAdapter<Header> {
static final int HEADER_TYPE_CATEGORY = 0;
static final int HEADER_TYPE_NORMAL = 1;
static final int HEADER_TYPE_SWITCH = 2;
private static final int HEADER_TYPE_COUNT = HEADER_TYPE_SWITCH + 1;
private final WifiEnabler mWifiEnabler;
private final BluetoothEnabler mBluetoothEnabler;
private final ProfileEnabler mProfileEnabler;
private AuthenticatorHelper mAuthHelper;
private static class HeaderViewHolder {
ImageView icon;
TextView title;
TextView summary;
Switch switch_;
}
private LayoutInflater mInflater;
static int getHeaderType(Header header) {
if (header.fragment == null && header.intent == null) {
return HEADER_TYPE_CATEGORY;
} else if (header.id == R.id.wifi_settings
|| header.id == R.id.bluetooth_settings
|| header.id == R.id.profiles_settings) {
return HEADER_TYPE_SWITCH;
} else {
return HEADER_TYPE_NORMAL;
}
}
@Override
public int getItemViewType(int position) {
Header header = getItem(position);
return getHeaderType(header);
}
@Override
public boolean areAllItemsEnabled() {
return false; // because of categories
}
@Override
public boolean isEnabled(int position) {
return getItemViewType(position) != HEADER_TYPE_CATEGORY;
}
@Override
public int getViewTypeCount() {
return HEADER_TYPE_COUNT;
}
@Override
public boolean hasStableIds() {
return true;
}
public HeaderAdapter(Context context, List<Header> objects,
AuthenticatorHelper authenticatorHelper) {
super(context, 0, objects);
mAuthHelper = authenticatorHelper;
mInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// Temp Switches provided as placeholder until the adapter replaces these with actual
// Switches inflated from their layouts. Must be done before adapter is set in super
mWifiEnabler = new WifiEnabler(context, new Switch(context));
mBluetoothEnabler = new BluetoothEnabler(context, new Switch(context));
mProfileEnabler = new ProfileEnabler(context, null, new Switch(context));
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
HeaderViewHolder holder;
Header header = getItem(position);
int headerType = getHeaderType(header);
View view = null;
if (convertView == null || headerType == HEADER_TYPE_SWITCH) {
holder = new HeaderViewHolder();
switch (headerType) {
case HEADER_TYPE_CATEGORY:
view = new TextView(getContext(), null,
android.R.attr.listSeparatorTextViewStyle);
holder.title = (TextView) view;
break;
case HEADER_TYPE_SWITCH:
view = mInflater.inflate(R.layout.preference_header_switch_item, parent,
false);
holder.icon = (ImageView) view.findViewById(R.id.icon);
holder.title = (TextView)
view.findViewById(com.android.internal.R.id.title);
holder.summary = (TextView)
view.findViewById(com.android.internal.R.id.summary);
holder.switch_ = (Switch) view.findViewById(R.id.switchWidget);
break;
case HEADER_TYPE_NORMAL:
view = mInflater.inflate(
R.layout.preference_header_item, parent,
false);
holder.icon = (ImageView) view.findViewById(R.id.icon);
holder.title = (TextView)
view.findViewById(com.android.internal.R.id.title);
holder.summary = (TextView)
view.findViewById(com.android.internal.R.id.summary);
break;
}
view.setTag(holder);
} else {
view = convertView;
holder = (HeaderViewHolder) view.getTag();
}
// All view fields must be updated every time, because the view may be recycled
switch (headerType) {
case HEADER_TYPE_CATEGORY:
holder.title.setText(header.getTitle(getContext().getResources()));
break;
case HEADER_TYPE_SWITCH:
// Would need a different treatment if the main menu had more switches
if (header.id == R.id.wifi_settings) {
mWifiEnabler.setSwitch(holder.switch_);
} else if (header.id == R.id.bluetooth_settings) {
mBluetoothEnabler.setSwitch(holder.switch_);
} else if (header.id == R.id.profiles_settings) {
mProfileEnabler.setSwitch(holder.switch_);
}
// No break, fall through on purpose to update common fields
//$FALL-THROUGH$
case HEADER_TYPE_NORMAL:
if (header.extras != null
&& header.extras.containsKey(ManageAccountsSettings.KEY_ACCOUNT_TYPE)) {
String accType = header.extras.getString(
ManageAccountsSettings.KEY_ACCOUNT_TYPE);
ViewGroup.LayoutParams lp = holder.icon.getLayoutParams();
lp.width = getContext().getResources().getDimensionPixelSize(
R.dimen.header_icon_width);
lp.height = lp.width;
holder.icon.setLayoutParams(lp);
Drawable icon = mAuthHelper.getDrawableForType(getContext(), accType);
holder.icon.setImageDrawable(icon);
} else {
holder.icon.setImageResource(header.iconRes);
}
holder.title.setText(header.getTitle(getContext().getResources()));
CharSequence summary = header.getSummary(getContext().getResources());
if (!TextUtils.isEmpty(summary)) {
holder.summary.setVisibility(View.VISIBLE);
holder.summary.setText(summary);
} else {
holder.summary.setVisibility(View.GONE);
}
break;
}
return view;
}
public void resume() {
mWifiEnabler.resume();
mBluetoothEnabler.resume();
mProfileEnabler.resume();
}
public void pause() {
mWifiEnabler.pause();
mBluetoothEnabler.pause();
mProfileEnabler.pause();
}
}