Question

所以我正在尝试的是如果DrawerLayout是打开的，而且我旋转屏幕，DrawerLayout应该关闭，但它不会

这是代码

package com.moammedx.learingmaterial;

import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.app.Fragment;
import android.support.v7.widget.Toolbar;
import android.widget.Toast;

public class NavigationDrwaerFragment extends Fragment {
    public static final String PREF_FILE_NAME = "testpref";
    public static final String KEY_USER_LEARNED_DRAWER = "user_learnd_drawer";

    private View contenerView;
    private ActionBarDrawerToggle mDrawerTolggle;

    private DrawerLayout mDrawerLayout;
    private boolean mUserLearnedDrawer;
    private boolean mFromSavedInstanceState;

    public NavigationDrwaerFragment() {
        // Required empty public constructor
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mUserLearnedDrawer = Boolean.valueOf(readFromPreferences(getActivity(), KEY_USER_LEARNED_DRAWER, "false"));
        if (savedInstanceState != null) {
            mFromSavedInstanceState = true;
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_navigation_drwaer, container, false);
    }


    public void SetUp(int fragmenID, DrawerLayout drawerlayout, Toolbar toolbar) {
        contenerView = getActivity().findViewById(fragmenID);
        mDrawerLayout = drawerlayout;
        mDrawerTolggle = new ActionBarDrawerToggle(getActivity(), drawerlayout, toolbar, R.string.drawer_open, R.string.drawer_close) {
            @Override
            public void onDrawerOpened(View drawerView) {
                if (!mUserLearnedDrawer) {
                    super.onDrawerOpened(drawerView);
                    mUserLearnedDrawer = true;
                    saveToPreferences(getActivity(), KEY_USER_LEARNED_DRAWER, mUserLearnedDrawer + "");
                }
                getActivity().invalidateOptionsMenu();

            }

            @Override
            public void onDrawerClosed(View drawerView) {
                super.onDrawerClosed(drawerView);
                getActivity().invalidateOptionsMenu();
                Toast.makeText(getActivity(), "onDrawerClosed", Toast.LENGTH_SHORT).show();
            }
        };

        if (!mUserLearnedDrawer && !mFromSavedInstanceState) {
            mDrawerLayout.openDrawer(contenerView);
        }
        if (mFromSavedInstanceState) {
            Toast.makeText(getActivity(), "close now", Toast.LENGTH_SHORT).show();
            mDrawerLayout.closeDrawer(contenerView);
        }
        mDrawerLayout.setDrawerListener(mDrawerTolggle);
        mDrawerLayout.post(new Runnable() {
            @Override
            public void run() {
                mDrawerTolggle.syncState();
            }
        });
    }

    public static void saveToPreferences(Context context, String preferencesName, String preferencesValue) {
        SharedPreferences sharedPreferences = context.getSharedPreferences(PREF_FILE_NAME, Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putString(preferencesName, preferencesValue);
        editor.apply();
    }

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

从主活动

调用SetUp方法

在onCreat中，我检查了savedInstanceState是否存在然后在SetUp中使用.colseDrawer来关闭DrawerLayout，但它没有关闭，我为吐司添加了仅用于测试，它在我旋转屏幕时显示

Answer 1

我是否可以通过在onResume

中添加.closeDrawer来解决这个问题

{{1}}

Answer 2

原因是因为DrawerLayout close命令的内部工作原理未包含在post runnable中。意思是，你的关闭命令会触发，但在它的状态保存开始之前并将其返回到它之前的状态（在这种情况下是打开）。要修复代码，只需将close命令的内容包装在post runnable中。它将在调用onCreate（）和onRestoreState（）之后执行，在旋转时关闭抽屉。

DrawerLayout旋转屏幕后不关闭

2 个答案: