在我的Android应用中，我有一个滑出导航抽屉。在导航抽屉中选择了一个项目时，它会加载新片段并突出显示您在导航栏中单击的项目。
我的问题是，在加载的新片段中，您可以单击该片段中的新项目，该片段会加载新片段并仍然保留导航抽屉。
在此实例中，您不再使用导航抽屉中列出的片段，但最后一项仍然突出显示，然后无法再次单击以返回。
如果我不能突出显示导航抽屉中的某个项目，如果它不是我的主要片段之一，然后在其中一个主要片段上重新突出显示，那么有什么想法吗？
这是我的导航抽屉代码：
public class MainDrawer2 extends FragmentActivity
{
private static final String EXTRA_NAV_ITEM = "extraNavItem";
private static final String STATE_CURRENT_NAV = "stateCurrentNav";
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private NavDrawerListAdapter mDrawerAdapter;
private ListView mDrawerList;
private CharSequence mTitle;
private CharSequence mDrawerTitle;
private MainNavItem mCurrentNavItem;
public static Intent createLaunchFragmentIntent(Context context, MainNavItem navItem)
{
return new Intent(context, MainDrawer2.class)
.putExtra(EXTRA_NAV_ITEM, navItem.ordinal());
}
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
Crashlytics.start(this);
mTitle = mDrawerTitle = getTitle();
mDrawerLayout = (DrawerLayout)findViewById(R.id.drawer_layout);
mDrawerList = (ListView)findViewById(R.id.drawer);
getActionBar().setDisplayHomeAsUpEnabled(true);
enableHomeButtonIfRequired();
mDrawerAdapter = new NavDrawerListAdapter(getApplicationContext());
mDrawerList.setAdapter(mDrawerAdapter);
mDrawerList.setOnItemClickListener(new ListView.OnItemClickListener()
{
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
displayNavFragment((MainNavItem)parent.getItemAtPosition(position));
}
});
mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
R.drawable.ic_drawer, R.string.app_name, R.string.app_name)
{
public void onDrawerClosed(View view)
{
getActionBar().setTitle(mTitle);
invalidateOptionsMenu();
}
public void onDrawerOpened(View drawerView)
{
getActionBar().setTitle(mDrawerTitle);
invalidateOptionsMenu();
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
if(getIntent().hasExtra(EXTRA_NAV_ITEM)){
MainNavItem navItem = MainNavItem.values()
[getIntent().getIntExtra(EXTRA_NAV_ITEM,
MainNavItem.STATISTICS.ordinal())];
displayNavFragment(navItem);
}
else if(savedInstanceState != null){
mCurrentNavItem = MainNavItem.values()
[savedInstanceState.getInt(STATE_CURRENT_NAV)];
setCurrentNavItem(mCurrentNavItem);
}
else{
displayNavFragment(MainNavItem.STATISTICS);
}
}
@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
private void enableHomeButtonIfRequired()
{
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH){
getActionBar().setHomeButtonEnabled(true);
}
}
public void setActionBarTitle(String title) {
getActionBar().setTitle(title);
}
@Override
public void setTitle(CharSequence title)
{
mTitle = title;
getActionBar().setTitle(mTitle);
}
@Override
protected void onPostCreate(Bundle savedInstanceState)
{
super.onPostCreate(savedInstanceState);
// Sync the toggle state after onRestoreInstanceState has occurred.
mDrawerToggle.syncState();
}
@Override
public void onConfigurationChanged(Configuration newConfig)
{
super.onConfigurationChanged(newConfig);
// Pass any configuration change to the drawer toggles
mDrawerToggle.onConfigurationChanged(newConfig);
}
@Override
protected void onSaveInstanceState(Bundle outState)
{
super.onSaveInstanceState(outState);
outState.putInt(STATE_CURRENT_NAV, mCurrentNavItem.ordinal());
}
@Override
public boolean onCreateOptionsMenu(Menu menu)
{
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
/*
@Override
public boolean onPrepareOptionsMenu(Menu menu)
{
// if nav drawer is opened, hide the action items
boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
return super.onPrepareOptionsMenu(menu);
}
*/
private void displayNavFragment(MainNavItem navItem)
{
if(navItem == mCurrentNavItem){
return;
}
Fragment fragment = Fragment.instantiate(this,
navItem.getFragClass().getName());
if(fragment != null){
getSupportFragmentManager().beginTransaction()
.replace(R.id.main, fragment)
.commit();
setCurrentNavItem(navItem);
}
}
private void setCurrentNavItem(MainNavItem navItem)
{
int position = navItem.ordinal();
// If navItem is in DrawerAdapter
if(position >= 0 && position < mDrawerAdapter.getCount()){
mDrawerList.setItemChecked(position, true);
}
else{
// navItem not in DrawerAdapter, de-select current item
if(mCurrentNavItem != null){
mDrawerList.setItemChecked(mCurrentNavItem.ordinal(), false);
}
}
mDrawerLayout.closeDrawer(mDrawerList);
setTitle(navItem.getTitleResId());
mCurrentNavItem = navItem;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
if(mDrawerLayout.isDrawerOpen(mDrawerList)) {
mDrawerLayout.closeDrawer(mDrawerList);
}
else {
mDrawerLayout.openDrawer(mDrawerList);
}
return true;
default:
return super.onOptionsItemSelected(item);
}
}
public void goToSearch(MenuItem item){
//go to search page
Fragment Fragment_one;
FragmentManager man= getSupportFragmentManager();
FragmentTransaction tran = man.beginTransaction();
Fragment_one = new Search();
tran.replace(R.id.main, Fragment_one);//tran.
tran.addToBackStack(null);
tran.commit();
}
public void scanBarcode(MenuItem item){
//open scanner
IntentIntegrator scanIntegrator = new IntentIntegrator(this);
scanIntegrator.initiateScan();
}
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
//retrieve scan result
IntentResult scanningResult = IntentIntegrator.parseActivityResult(requestCode, resultCode, intent);
if (scanningResult != null) {
//we have a result
String scanContent = scanningResult.getContents();
//todo: set scan content into setting, load new fragment which calls async task below. New
//todo: fragment will have same ui as search. :-)
Fragment Fragment_one;
FragmentManager man= this.getSupportFragmentManager();
FragmentTransaction tran = man.beginTransaction();
Fragment_one = new BarcodeFrag(scanContent);
tran.replace(R.id.main, Fragment_one);//tran.
tran.addToBackStack(null);
//tran.commit();
tran.commitAllowingStateLoss();
}
else{
Toast toast = Toast.makeText(getApplicationContext(),
"No scan data received!", Toast.LENGTH_SHORT);
toast.show();
}
}
}
然后我有一个名为main nav item的枚举：
public enum MainNavItem
{
// Displayed in NavDrawerListAdapter
STATISTICS("Your Statistics", R.layout.statistics_pagelayout, StatisticsTab.class),
DISCOVER ("Discover", R.layout.activity_discover, DiscoverTab.class),
PORTFOLIO ("Portfolio", R.layout.activity_portfolio, Portfolio.class),
LISTS ("Your Lists", R.layout.activity_search, AllLists.class),
NEWS ("News", R.layout.activity_news, NewsWeb.class),
Find ("Nearby Breweries", R.layout.beer_location_list, FindBrewery.class),
CONTACT ("Contact", R.layout.activity_contact, ContactPage.class),
// Items NOT displayed in NavDrawerListAdapter
SEARCH ("Search", R.layout.activity_search, Search.class),
;
private static MainNavItem LAST_NAV_ITEM = CONTACT;
private String mTitleResId;
private int mLayoutResId;
private Class<? extends Fragment> mFragClass;
private MainNavItem(String titleResId, int layoutResId, Class<? extends Fragment> fragClass)
{
mTitleResId = titleResId;
mLayoutResId = layoutResId;
mFragClass = fragClass;
}
public int getLayoutResId()
{
return mLayoutResId;
}
public String getTitleResId()
{
return mTitleResId;
}
public Class<? extends Fragment> getFragClass()
{
return mFragClass;
}
public static MainNavItem[] getNavAdapterItems()
{
int count = LAST_NAV_ITEM.ordinal() + 1;
MainNavItem[] adapterItems = new MainNavItem[count];
for(int i = 0; i < count; i++){
adapterItems[i] = values()[i];
}
return adapterItems;
}
}
更新：
我只是试图注释掉这两行以关闭一般的突出显示，以便用户可以在我的导航抽屉中重新选择一个项目。
private void setCurrentNavItem(MainNavItem navItem)
{
int position = navItem.ordinal();
// If navItem is in DrawerAdapter
if(position >= 0 && position < mDrawerAdapter.getCount()){
//mDrawerList.setItemChecked(position, true);
}
else{
// navItem not in DrawerAdapter, de-select current item
if(mCurrentNavItem != null){
//mDrawerList.setItemChecked(mCurrentNavItem.ordinal(), false);
}
}
mDrawerLayout.closeDrawer(mDrawerList);
setTitle(navItem.getTitleResId());
mCurrentNavItem = navItem;
}
当应用程序现在为第一次启动时，没有任何内容突出显示，但是当我点击某些内容时它会突出显示，我无法再次单击它以重新加载该片段。还有其他想法吗？
答案 0 :(得分：6)
我只是将我的项目分组如下， android：checkableBehavior =“none”这一行非常重要，并确保它应该是无。
<group android:checkableBehavior="none">
<item
android:id="@+id/nav_home"
android:icon="@drawable/left_menu_home"
android:title="@string/home" />
<item
android:id="@+id/nav_account_settings"
android:icon="@drawable/left_menu_account_settings"
android:title="@string/accountSettings" />
</group>
答案 1 :(得分：4)
想出来。画中没有项目的最简单方法是在你的xml中为draw linst，choiceMode应该是none：
<FrameLayout
android:id="@+id/main"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</FrameLayout>
<ListView
android:id="@+id/drawer"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:divider="@android:color/white"
android:background="@android:color/black"
android:choiceMode="none"/>
答案 2 :(得分：1)
您可以通过调用menuItem.setChecked(false);
答案 3 :(得分：0)
关于如何在导航抽屉不是我的主要片段之一时取消突出显示项目的任何想法
int toClear=mDrawerList.getCheckedItemPosition();
if (toClear >= 0) {
mDrawerList.setItemChecked(toClear, false);
}
然后在其中一个主要片段上重新突出显示？
使用与可见片段对应的位置调用setItemChecked()，为第二个参数调用true。
This sample project证明了这一点。我使用post()来控制何时更新ListView中的已检查状态有点草率，但它已经足够了。