Question

我有新的导航抽屉用于棒棒糖，我看到新的抽屉图标（汉堡包），当抽屉打开时，它切换到＆lt; - （左箭头）图标，当抽屉关闭时，它切换回抽屉图标。到目前为止完美无缺。

当抽屉中选择了某些东西时，我正在用抽屉替换主片段。我能够看到新片段和抽屉关闭，但仍然看到＆lt; - icon，我想看到抽屉图标（汉堡包），而不是更换主片段时的箭头。我该如何控制？

MainActivity.java

package com.lollipop.navdrawer;

import android.app.Activity;

import android.app.ActionBar;
import android.app.Fragment;
import android.app.FragmentManager;
import android.content.Context;
import android.content.res.Configuration;
import android.os.Build;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.DrawerLayout;
import android.widget.ArrayAdapter;
import android.widget.ScrollView;
import android.widget.TextView;


public class MyActivity extends ActionBarActivity
        implements NavigationDrawerFragment.NavigationDrawerCallbacks {

    private NavigationDrawerFragment mNavigationDrawerFragment;
    private View container;
    private CharSequence mTitle;

    public void setupToolbar(View viewToolbar){
        Toolbar toolbar = (Toolbar)viewToolbar;
        if (toolbar != null) {
            setSupportActionBar(toolbar);
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            getSupportActionBar().setHomeButtonEnabled(true);
        }

    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_my);

        container = findViewById(R.id.container);
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.container, new MyFragment())
                .commit();

        mNavigationDrawerFragment = (NavigationDrawerFragment)
                getFragmentManager().findFragmentById(R.id.navigation_drawer);
        mTitle = getTitle();

        // Set up the drawer.
        mNavigationDrawerFragment.setUp(
                R.id.navigation_drawer,
                (DrawerLayout) findViewById(R.id.drawer_layout));

        ScrollView scrollView = (ScrollView)findViewById(R.id.scroll_view);
    }

    @Override
    public void onNavigationDrawerItemSelected(int position) {
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.container, new MyFragment())
                .commit();
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        if (!mNavigationDrawerFragment.isDrawerOpen()) {
            getMenuInflater().inflate(R.menu.my, menu);
            return true;
        }
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        mNavigationDrawerFragment.mDrawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        mNavigationDrawerFragment.mDrawerToggle.onConfigurationChanged(newConfig);
    }

    @Override
    public void onBackPressed() {
        if(mNavigationDrawerFragment.mDrawerLayout.isDrawerOpen(Gravity.START|Gravity.LEFT)){
            mNavigationDrawerFragment.mDrawerLayout.closeDrawers();
            return;
        }
        super.onBackPressed();
    }
}

NavigationDrawerFragment.java

package com.lollipop.navdrawer;


import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;

public class NavigationDrawerFragment extends Fragment {

    private static final String STATE_SELECTED_POSITION = "selected_navigation_drawer_position";

    private static final String PREF_USER_LEARNED_DRAWER = "navigation_drawer_learned";

    private NavigationDrawerCallbacks mCallbacks;

    public ActionBarDrawerToggle mDrawerToggle;

    public DrawerLayout mDrawerLayout;
    private ListView mDrawerListView;
    private View mFragmentContainerView;

    private int mCurrentSelectedPosition = 0;
    private boolean mFromSavedInstanceState;
    private boolean mUserLearnedDrawer;

    public NavigationDrawerFragment() {
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(getActivity());
        mUserLearnedDrawer = sp.getBoolean(PREF_USER_LEARNED_DRAWER, false);

        if (savedInstanceState != null) {
            mCurrentSelectedPosition = savedInstanceState.getInt(STATE_SELECTED_POSITION);
            mFromSavedInstanceState = true;
        }

        selectItem(mCurrentSelectedPosition);
    }

    @Override
    public void onActivityCreated (Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        setHasOptionsMenu(true);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        mDrawerListView = (ListView) inflater.inflate(
                R.layout.fragment_navigation_drawer, container, false);
        mDrawerListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                selectItem(position);
            }
        });
        mDrawerListView.setAdapter(new ArrayAdapter<String>(
                getActivity(),
                android.R.layout.simple_list_item_activated_1,
                android.R.id.text1,
                new String[]{
                        getString(R.string.title_section1),
                        getString(R.string.title_section2),
                        getString(R.string.title_section3),
                }));

        mDrawerListView.setItemChecked(mCurrentSelectedPosition, true);
        return mDrawerListView;
    }

    public boolean isDrawerOpen() {
        return mDrawerLayout != null && mDrawerLayout.isDrawerOpen(mFragmentContainerView);
    }

    public void setUp(int fragmentId, DrawerLayout drawerLayout) {
        mFragmentContainerView = getActivity().findViewById(fragmentId);
        mDrawerLayout = drawerLayout;

        mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);

        Toolbar mToolbar = (Toolbar) getActivity().findViewById(R.id.toolbar);

        mDrawerToggle = new ActionBarDrawerToggle(
                getActivity(),                    /* host Activity */
                mDrawerLayout,                    /* DrawerLayout object */
                mToolbar,             /* nav drawer image to replace 'Up' caret */
                R.string.navigation_drawer_open,  /* "open drawer" description for accessibility */
                R.string.navigation_drawer_close  /* "close drawer" description for accessibility */
        ) {
            @Override
            public void onDrawerClosed(View drawerView) {
                super.onDrawerClosed(drawerView);
                if (!isAdded()) {
                    return;
                }

                getActivity().invalidateOptionsMenu(); // calls onPrepareOptionsMenu()
            }

            @Override
            public void onDrawerOpened(View drawerView) {
                super.onDrawerOpened(drawerView);
                if (!isAdded()) {
                    return;
                }

                if (!mUserLearnedDrawer) {
                    // The user manually opened the drawer; store this flag to prevent auto-showing
                    // the navigation drawer automatically in the future.
                    mUserLearnedDrawer = true;
                    SharedPreferences sp = PreferenceManager
                            .getDefaultSharedPreferences(getActivity());
                    sp.edit().putBoolean(PREF_USER_LEARNED_DRAWER, true).apply();
                }

                getActivity().invalidateOptionsMenu(); // calls onPrepareOptionsMenu()
            }
        };

        mDrawerLayout.setDrawerListener(mDrawerToggle);

        // If the user hasn't 'learned' about the drawer, open it to introduce them to the drawer,
        // per the navigation drawer design guidelines.
        if (!mUserLearnedDrawer && !mFromSavedInstanceState) {
            mDrawerLayout.openDrawer(mFragmentContainerView);
        }

        // Defer code dependent on restoration of previous instance state.
        mDrawerLayout.post(new Runnable() {
            @Override
            public void run() {
                mDrawerToggle.syncState();
            }
        });

        mDrawerLayout.setDrawerListener(mDrawerToggle);
    }

    private void selectItem(int position) {
        mCurrentSelectedPosition = position;
        if (mDrawerListView != null) {
            mDrawerListView.setItemChecked(position, true);
        }
        if (mDrawerLayout != null) {
            mDrawerLayout.closeDrawer(mFragmentContainerView);
        }
        if (mCallbacks != null) {
            mCallbacks.onNavigationDrawerItemSelected(position);
        }
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        try {
            mCallbacks = (NavigationDrawerCallbacks) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException("Activity must implement NavigationDrawerCallbacks.");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mCallbacks = null;
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putInt(STATE_SELECTED_POSITION, mCurrentSelectedPosition);
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        // Forward the new configuration the drawer toggle component.
        mDrawerToggle.onConfigurationChanged(newConfig);
    }

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        if (mDrawerLayout != null && isDrawerOpen()) {
            inflater.inflate(R.menu.global, menu);
        }
        super.onCreateOptionsMenu(menu, inflater);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (mDrawerToggle.onOptionsItemSelected(item)) {
            return true;
        }

        if (item.getItemId() == R.id.action_example) {
            Toast.makeText(getActivity(), "Example action.", Toast.LENGTH_SHORT).show();
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    /**
     * Per the navigation drawer design guidelines, updates the action bar to show the global app
     * 'context', rather than just what's in the current screen.
     */
    private void showGlobalContextActionBar() {
        ActionBar actionBar = getActionBar();
        actionBar.setDisplayShowTitleEnabled(true);
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
        actionBar.setTitle(R.string.app_name);
    }

    private ActionBar getActionBar() {
        return getActivity().getActionBar();
    }

    /**
     * Callbacks interface that all activities using this fragment must implement.
     */
    public static interface NavigationDrawerCallbacks {
        /**
         * Called when an item in the navigation drawer is selected.
         */
        void onNavigationDrawerItemSelected(int position);
    }
}

MyFragment.java

package com.lollipop.navdrawer;

import android.app.Activity;
import android.app.Dialog;
import android.app.Fragment;
import android.app.ProgressDialog;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

import java.util.Arrays;
import java.util.List;


public class MyFragment extends Fragment {
    private MyActivity mActivity;

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

        View view = inflater.inflate(R.layout.fragment_my, container, false);
        mActivity = (MyActivity)getActivity();
        mActivity.setupToolbar(view.findViewById(R.id.toolbar));
        return view;
    }
}

Answer 1

您必须在ActionBarDrawerToggle.syncState()功能上致电setupToolbar。由于您无法访问活动中的mDrawerToggle，因此您必须在片段上创建一个getter，并将其称为mNavigationDrawerFragment.getDrawerToggle().syncState();

Android 5.0导航抽屉：在抽屉中选择项目时，抽屉图标不会变回

1 个答案: