Creating a Navigation Drawer中使用的Navigation Drawer的android:minSdkVersion="14",现在Android API Version 小于14的还有30%左右呢。Android个版本的占有量可参考 Platform Version。
Android Platform Version
我们的应用为了适配不同的版本,需要降低minSdkVersion,作者一般适配SDK到API 7。这一篇博文也是把Creating a Navigation Drawer的例子适配到API 7 。例子中降低API最主要的修改Action Bar,Action Bar是API 11才出现的,适配到API 7,我们使用了actionbarsherlock.
修改后的代码:
public class MainActivity extends SherlockFragmentActivity { private DrawerLayout mDrawerLayout; private ListView mDrawerList; private ActionBarDrawerToggle mDrawerToggle; private CharSequence mDrawerTitle; private CharSequence mTitle; private String[] mPlanetTitles; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mTitle = mDrawerTitle = getTitle(); mPlanetTitles = getResources().getStringArray(R.array.planets_array); mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout); mDrawerList = (ListView) findViewById(R.id.left_drawer); // set a custom shadow that overlays the main content when the drawer opens mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START); // set up the drawer's list view with items and click listener mDrawerList.setAdapter(new ArrayAdapter<String>(this, R.layout.drawer_list_item, mPlanetTitles)); mDrawerList.setOnItemClickListener(new DrawerItemClickListener()); // enable ActionBar app icon to behave as action to toggle nav drawer getSupportActionBar().setDisplayHomeAsUpEnabled(true); getSupportActionBar().setHomeButtonEnabled(true); // ActionBarDrawerToggle ties together the the proper interactions // between the sliding drawer and the action bar app icon mDrawerToggle = new ActionBarDrawerToggle( this, /* host Activity */ mDrawerLayout, /* DrawerLayout object */ R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */ R.string.drawer_open, /* "open drawer" description for accessibility */ R.string.drawer_close /* "close drawer" description for accessibility */ ) { /** Called when a drawer has settled in a completely closed state. */ public void onDrawerClosed(View view) { getSupportActionBar().setTitle(mTitle); } /** Called when a drawer has settled in a completely open state. */ public void onDrawerOpened(View drawerView) { getSupportActionBar().setTitle(mDrawerTitle); } }; mDrawerLayout.setDrawerListener(mDrawerToggle); if (savedInstanceState == null) { selectItem(0); } } @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getSupportMenuInflater(); inflater.inflate(R.menu.main, menu); return super.onCreateOptionsMenu(menu); } /* Called whenever we call invalidateOptionsMenu() */ @Override public boolean onPrepareOptionsMenu(Menu menu) { // If the nav drawer is open, hide action items related to the content view boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList); menu.findItem(R.id.action_websearch).setVisible(!drawerOpen); return super.onPrepareOptionsMenu(menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // The action bar home/up action should open or close the drawer. // ActionBarDrawerToggle will take care of this. // if (mDrawerToggle.onOptionsItemSelected(item)) { // return true; // } // Handle action buttons switch(item.getItemId()) { case android.R.id.home: handleNavigationDrawerToggle(); return true; case R.id.action_websearch: // create intent to perform web search for this planet Intent intent = new Intent(Intent.ACTION_WEB_SEARCH); intent.putExtra(SearchManager.QUERY, getSupportActionBar().getTitle()); // catch event that there's no activity to handle intent if (intent.resolveActivity(getPackageManager()) != null) { startActivity(intent); } else { Toast.makeText(this, R.string.app_not_available, Toast.LENGTH_LONG).show(); } return true; default: return super.onOptionsItemSelected(item); } } private void handleNavigationDrawerToggle() { if (mDrawerLayout.isDrawerOpen(mDrawerList)) { mDrawerLayout.closeDrawer(mDrawerList); } else { mDrawerLayout.openDrawer(mDrawerList); } } /* The click listner for ListView in the navigation drawer */ private class DrawerItemClickListener implements ListView.OnItemClickListener { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { selectItem(position); } } private void selectItem(int position) { // update the main content by replacing fragments Fragment fragment = new PlanetFragment(); Bundle args = new Bundle(); args.putInt(PlanetFragment.ARG_PLANET_NUMBER, position); fragment.setArguments(args); FragmentManager fragmentManager = getSupportFragmentManager(); fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit(); // update selected item and title, then close the drawer mDrawerList.setItemChecked(position, true); setTitle(mPlanetTitles[position]); mDrawerLayout.closeDrawer(mDrawerList); } @Override public void setTitle(CharSequence title) { mTitle = title; getSupportActionBar().setTitle(mTitle); } /** * When using the ActionBarDrawerToggle, you must call it during * onPostCreate() and onConfigurationChanged()... */ @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 toggls mDrawerToggle.onConfigurationChanged(newConfig); } /** * Fragment that appears in the "content_frame", shows a planet */ public static class PlanetFragment extends Fragment { public static final String ARG_PLANET_NUMBER = "planet_number"; public PlanetFragment() { // Empty constructor required for fragment subclasses } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_planet, container, false); int i = getArguments().getInt(ARG_PLANET_NUMBER); String planet = getResources().getStringArray(R.array.planets_array)[i]; int imageId = getResources().getIdentifier(planet.toLowerCase(Locale.getDefault()), "drawable", getActivity().getPackageName()); ((ImageView) rootView.findViewById(R.id.image)).setImageResource(imageId); getActivity().setTitle(planet); return rootView; } } }
如果只修改JAVA代码,运行应用还是会出现异常:
08-13 13:26:15.909: E/AndroidRuntime(6832): FATAL EXCEPTION: main 08-13 13:26:15.909: E/AndroidRuntime(6832): android.view.InflateException: Binary XML file line #2: Error inflating class <unknown> 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.LayoutInflater.createView(LayoutInflater.java:518) 08-13 13:26:15.909: E/AndroidRuntime(6832): at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:56) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:568) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.LayoutInflater.inflate(LayoutInflater.java:386) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.LayoutInflater.inflate(LayoutInflater.java:320) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:332) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.ArrayAdapter.getView(ArrayAdapter.java:323) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.AbsListView.obtainView(AbsListView.java:1495) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.ListView.measureHeightOfChildren(ListView.java:1216) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.ListView.onMeasure(ListView.java:1127) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.View.measure(View.java:8335) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.RelativeLayout.measureChild(RelativeLayout.java:566) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:381) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.View.measure(View.java:8335) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.View.measure(View.java:8335) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.LinearLayout.measureVertical(LinearLayout.java:531) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.View.measure(View.java:8335) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.View.measure(View.java:8335) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.ViewRoot.performTraversals(ViewRoot.java:843) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.ViewRoot.handleMessage(ViewRoot.java:1892) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.os.Handler.dispatchMessage(Handler.java:99) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.os.Looper.loop(Looper.java:130) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.app.ActivityThread.main(ActivityThread.java:3835) 08-13 13:26:15.909: E/AndroidRuntime(6832): at java.lang.reflect.Method.invokeNative(Native Method) 08-13 13:26:15.909: E/AndroidRuntime(6832): at java.lang.reflect.Method.invoke(Method.java:507) 08-13 13:26:15.909: E/AndroidRuntime(6832): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864) 08-13 13:26:15.909: E/AndroidRuntime(6832): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622) 08-13 13:26:15.909: E/AndroidRuntime(6832): at dalvik.system.NativeStart.main(Native Method) 08-13 13:26:15.909: E/AndroidRuntime(6832): Caused by: java.lang.reflect.InvocationTargetException 08-13 13:26:15.909: E/AndroidRuntime(6832): at java.lang.reflect.Constructor.constructNative(Native Method) 08-13 13:26:15.909: E/AndroidRuntime(6832): at java.lang.reflect.Constructor.newInstance(Constructor.java:415) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.LayoutInflater.createView(LayoutInflater.java:505) 08-13 13:26:15.909: E/AndroidRuntime(6832): ... 32 more 08-13 13:26:15.909: E/AndroidRuntime(6832): Caused by: java.lang.UnsupportedOperationException: Can't convert to dimension: type=0x2 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.content.res.TypedArray.getDimensionPixelSize(TypedArray.java:463) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.view.View.<init>(View.java:1978) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.TextView.<init>(TextView.java:350) 08-13 13:26:15.909: E/AndroidRuntime(6832): at android.widget.TextView.<init>(TextView.java:343) 08-13 13:26:15.909: E/AndroidRuntime(6832): ... 35 more
这个异常是 drawer_list_item.xml文件的内容产生的,drawer_list_item.xml内容:
<TextView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@android:id/text1" android:layout_width="match_parent" android:layout_height="wrap_content" android:textAppearance="?android:attr/textAppearanceListItemSmall" android:gravity="center_vertical" android:paddingLeft="16dp" android:paddingRight="16dp" android:textColor="#fff" android:background="?android:attr/activatedBackgroundIndicator" android:minHeight="?android:attr/listPreferredItemHeightSmall"/>
而在API 14之前的版本中,下面的三个属性会报异常:
<TextView xmlns:android="http://schemas.android.com/apk/res/android" android:textAppearance="?android:attr/textAppearanceListItemSmall" android:background="?android:attr/activatedBackgroundIndicator" android:minHeight="?android:attr/listPreferredItemHeightSmall"/>
如果想适配更低的版本需要做如下的修改:
1)修改drawer_list_item.xml文件,使用自定义的属性
<?xml version="1.0" encoding="UTF-8"?> <TextView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@android:id/text1" android:layout_width="match_parent" android:layout_height="wrap_content" android:background="?attr/myapp_activatedBackgroundIndicator" android:gravity="center_vertical" android:minHeight="?attr/myapp_listPreferredItemHeightSmall" android:paddingLeft="16dp" android:paddingRight="16dp" android:textAppearance="?attr/myapp_textAppearanceListItemSmall" />
2)在 values/attrs.xml文件中声明自定义属性
<?xml version="1.0" encoding="utf-8"?> <resources> <declare-styleable name="AppTheme"> <!-- Attributes below are needed to support the navigation drawer on Android 3.x. --> <!-- A smaller, sleeker list item height. --> <attr name="myapp_listPreferredItemHeightSmall" format="dimension" /> <!-- Drawable used as a background for activated items. --> <attr name="myapp_activatedBackgroundIndicator" format="reference" /> <!-- The preferred TextAppearance for the primary text of small list items. --> <attr name="myapp_textAppearanceListItemSmall" format="reference" /> </declare-styleable> </resources>
3) 在values-11/styles.xml文件中添加
<!-- Base application theme, dependent on API level. This theme is replaced by AppBaseTheme from res/values-vXX/styles.xml on newer devices. --> <style name="AppBaseTheme" parent="Theme.Sherlock.Light.DarkActionBar"> <!-- Theme customizations available in newer API levels can go in res/values-vXX/styles.xml, while customizations related to backward-compatibility can go here. --> <!-- Implementation of attributes needed for the navigation drawer as the default implementation is based on API-14. --> <item name="myapp_listPreferredItemHeightSmall">48dip</item> <item name="myapp_textAppearanceListItemSmall">@style/MyappDrawerMenu</item> <item name="myapp_activatedBackgroundIndicator">@android:color/transparent</item> </style> <style name="MyappDrawerMenu"> <item name="android:textSize">16sp</item> <item name="android:textStyle">bold</item> <item name="android:textColor">@android:color/black</item> </style>
4) 在values-v14/styles.xml文件中添加
<!-- Base application theme for API 14+. This theme completely replaces AppBaseTheme from BOTH res/values/styles.xml and res/values-v11/styles.xml on API 14+ devices. --> <style name="AppBaseTheme" parent="android:Theme.Holo.Light.DarkActionBar"> <!-- For API-14 and above the default implementation of the navigation drawer menu is used. Below APU-14 a custom implementation is used. --> <item name="myapp_listPreferredItemHeightSmall">?android:attr/listPreferredItemHeightSmall</item> <item name="myapp_textAppearanceListItemSmall">?android:attr/textAppearanceListItemSmall</item> <item name="myapp_activatedBackgroundIndicator">?android:attr/activatedBackgroundIndicator</item> </style>
OK,经过上面步骤,运行成功,这样上一篇的例子就能很好的适配到API 7了。
代码下载:Demo