Question

我有这个导航抽屉。当应用程序打开时，它工作正常，它不会显示。但是当我通过它导航到一个菜单然后按回来时，它不应该出现，但确实如此。我怎样才能解决这个问题。谢谢！

import android.support.v4.app.Fragment;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import java.util.ArrayList;
import java.util.List;


public class NavigationDrawer extends Fragment implements     NavDrawerRVAdapter.ClickListener {
private RecyclerView recyclerView;
public static final String KEY_USER_LEARNED_DRAWER = "user_learned_drawer";
private View containerView;
public static final String PREF_FILE_NAME = "testpref";
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private boolean mUserLearnedDrawer;
private boolean mFromSavedInstanceState;
private NavDrawerRVAdapter adapter;

public NavigationDrawer() {
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View layout = inflater.inflate(R.layout.navigation_drawer, container, false);
    recyclerView = (RecyclerView) layout.findViewById(R.id.drawerList);
    adapter = new NavDrawerRVAdapter(getActivity(), getData());
    adapter.setClickListener(this);
    recyclerView.setAdapter(adapter);
    recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
    return layout;
}



// Oncreate & Set up for navdrawer
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
   // mUserLearnedDrawer =readFromPreferences(getActivity(),KEY_USER_LEARNED_DRAWER,true);
    mUserLearnedDrawer =true;
    if (savedInstanceState != null)
        mFromSavedInstanceState = true;
}

public void setUp(int fragmentId, DrawerLayout drawerLayout, final Toolbar toolbar) {
    containerView = getActivity().findViewById(fragmentId);
    mDrawerLayout = drawerLayout;
    mDrawerLayout.setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS);
    mDrawerToggle = new ActionBarDrawerToggle(getActivity(), drawerLayout, toolbar, R.string.drawer_open, R.string.drawer_close) {
        @Override
        public void onDrawerOpened(View drawerView) {
            super.onDrawerOpened(drawerView);
            if (!mUserLearnedDrawer) {
                mUserLearnedDrawer = true;
                SaveToPreferences(getActivity(), KEY_USER_LEARNED_DRAWER, true );
            }
            getActivity().invalidateOptionsMenu();
        }

        @Override
        public void onDrawerClosed(View drawerView) {
            super.onDrawerClosed(drawerView);
            getActivity().invalidateOptionsMenu();
        }

        @Override
        public void onDrawerSlide(View drawerView, float slideOffset) {
            super.onDrawerSlide(drawerView, slideOffset);
            toolbar.setAlpha(1 - slideOffset / 2);
        }
    };
    if (!mUserLearnedDrawer&&!mFromSavedInstanceState) {
        mDrawerLayout.openDrawer(containerView);

    }

    mDrawerLayout.setDrawerListener(mDrawerToggle);
    mDrawerLayout.post(new Runnable() {
        @Override
        public void run() {
            mDrawerToggle.syncState();
        }
    });

}

public static void SaveToPreferences(Context context, String preferenceName, boolean preferenceValue) {
    SharedPreferences sharedPreferences = context.getSharedPreferences(PREF_FILE_NAME, Context.MODE_PRIVATE);
    SharedPreferences.Editor editor = sharedPreferences.edit();
    editor.putBoolean(preferenceName, preferenceValue);
    editor.apply();
}

public static boolean readFromPreferences(Context context, String preferenceName, boolean defaultValue) {
    SharedPreferences sharedPreferences = context.getSharedPreferences(PREF_FILE_NAME, Context.MODE_PRIVATE);
    return sharedPreferences.getBoolean(preferenceName, defaultValue);
}

@Override
public void itemClicked(View view, int position) {
    switch (position) {
        case 1:
            startActivity(new Intent(getActivity(), AccountsAndCards.class));
            break;
        default:
            startActivity(new Intent(getActivity(), AccountsAndCards.class));
    }

}

}

Answer 1

在您的抽屉itemClicked方法中关闭抽屉。

mDrawerLayout.closeDrawers();

导航抽屉在返回主要活动时保持打开状态

1 个答案: