导航抽屉图标动画

Question

我开始为 Android 编写应用程序。我对左上角NavigationDrawer 图标的Animation 有疑问。首次启动应用程序时它可以正常工作，但是当我从 NavgationDrawer 的列表中选择一个项目时，即使 `NavigationDrawer 正常关闭，它的图标仍处于“打开”状态。

这是我的MainActivity：

import android.app.*;
import android.os.*;
import android.view.*;
import android.widget.*;
import android.app.ActionBar;
import android.os.Bundle;
import android.app.Activity;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.widget.DrawerLayout;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.content.res.*;

public class MainActivity extends FragmentActivity {

    ActionBarDrawerToggle icon;
    final String[] listContent ={"Accueil","Fiche technique","Pilotes","Ecuries"};
    final String[] fragments ={
            "com.mycompany.f1holo.MainPageFragment",
            "com.mycompany.f1holo.FirstFragment",
            "com.mycompany.f1holo.SecondFragment",
            "com.mycompany.f1holo.ThirdFragment"};

    private ActionBarDrawerToggle actionBarDrawerToggle;

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

        ArrayAdapter<String> ad = new ArrayAdapter<String>(getActionBar().getThemedContext(), android.R.layout.simple_list_item_1, listContent);

        final DrawerLayout drawer = (DrawerLayout)findViewById(R.id.drawer_layout);
        final ListView list = (ListView) findViewById(R.id.drawer);

        actionBarDrawerToggle = new ActionBarDrawerToggle(
                this,
                drawer,
                R.drawable.navdrawer,
                R.string.open,
                R.string.close);

        drawer.setDrawerListener(actionBarDrawerToggle);

        getActionBar().setDisplayHomeAsUpEnabled(true);
        getActionBar().setHomeButtonEnabled(true);

        list.setAdapter(ad);
        list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView parent, View view, final int position, long id) {
                drawer.setDrawerListener( new DrawerLayout.SimpleDrawerListener(){

                    @Override
                    public void onDrawerClosed(View drawerView){
                        super.onDrawerClosed(drawerView);
                        FragmentTransaction transition = getSupportFragmentManager().beginTransaction();
                        transition.replace(R.id.mains, Fragment.instantiate(MainActivity.this, fragments[position]));
                        transition.commit();
                    }
                });
                drawer.closeDrawer(list);
            }
        });
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);

        actionBarDrawerToggle.syncState();
    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (actionBarDrawerToggle.onOptionsItemSelected(item)) {
            return true;
        }
        switch (item.getItemId())
        {
            case R.id.mainMenuAbout:
                Toast.makeText(this, "F1 Holo", Toast.LENGTH_SHORT).show();
                return true;
            case R.id.mainMenuQuitter:
                finish();
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {    
        getMenuInflater().inflate(R.menu.main_menu, menu);
        getMenuInflater().inflate(R.menu.main_about, menu);
        return true;    
    }
}

这是我的FirstFragment：

import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class FirstFragment extends Fragment {

    public static Fragment newInstance(Context context) {
        FirstFragment frag = new FirstFragment();
        return frag;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle   savedInstanceState) {
        ViewGroup root = (ViewGroup) inflater.inflate(R.layout.first_fragment_layout,  null);
        return root;
    }
}

Answer 1

我已经找到了解决方案，而且很明显，我可能会因为之前没有注意到而自责...

问题出在这里：

list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView parent, View view, final int position, long id) {
        drawer.setDrawerListener( new DrawerLayout.SimpleDrawerListener() {

            @Override
            public void onDrawerClosed(View drawerView) {
                super.onDrawerClosed(drawerView);
                FragmentTransaction transition = getSupportFragmentManager().beginTransaction();
                transition.replace(R.id.mains, Fragment.instantiate(MainActivity.this, fragments[position]));
                transition.commit();
            }
        });
        drawer.closeDrawer(list);
    }
});

在此 OnClickListener 中，您正在设置一个新的 SimpleDrawerListener 并因此覆盖此行：

drawer.setDrawerListener(actionBarDrawerToggle);

这会将ActionBarDrawerToogle 与DrawerLayout 断开连接，从而停止播放动画...这就是您所需要的：

list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView parent, View view, final int position, long id) {
        FragmentTransaction transition = getSupportFragmentManager().beginTransaction();
        transition.replace(R.id.mains, Fragment.instantiate(MainActivity.this, fragments[position]));
        transition.commit();

        drawer.closeDrawer(list);
    }
});

你为什么要这样做呢？它只会在用户选择项目和实际更改的内容之间造成延迟。如果是因为性能问题 - 可能是 NavigationDrawer 的关闭动画播放不正确 - 那么做这样的事情可能是合适的，但无论如何如果你决定实现这个，请这样做：

首先创建名为drawerItemSelection的全局变量：

private String drawerItemSelection = null;

然后像这样实现你的ItemClickListener：

list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView parent, View view, final int position, long id) {
        drawerItemSelection = fragments[position];

        drawer.closeDrawer(list);
    }
});

最后在您的onCreate() 方法中实现ActionBarDrawerToogle，如下所示：

actionBarDrawerToggle = new ActionBarDrawerToggle(this, drawer, R.drawable.navdrawer, R.string.open, R.string.close) {

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

        if(drawerItemSelection != null) {
            FragmentTransaction transition = getSupportFragmentManager().beginTransaction();
            transition.replace(R.id.mains, Fragment.instantiate(MainActivity.this, drawerItemSelection));
            transition.commit();

            drawerItemSelection = null;
        }
    }
};

如果您还有其他问题，请随时提问！