我正在为Android开发导航抽屉(Navigation Drawer)。
根据我的需求,我需要在导航抽屉中显示项目的网格视图和列表视图。我在布局xml文件中创建了一个LinearLayout,并将两个小部件(GridView和ListView)放置在LinearLayout中。
当我运行该文件时,我得到以下错误:
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.navigationdrawer3/com.example.navigationdrawer3.MainActivity}: java.lang.ClassCastException: android.widget.FrameLayout$LayoutParams cannot be cast to android.support.v4.widget.DrawerLayout$LayoutParams
下面是我的Java、Logcat和NavigationDrawer布局文件:
MainActivity.java
public class MainActivity extends Activity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private CharSequence mDrawerTitle;
//@SuppressWarnings("unused")
private CharSequence mTitle;
private String[] mGalaxyTitles;
private GridView mDrawerGrid;
private LinearLayout mDrawerLinear;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTitle = mDrawerTitle = getTitle();
mGalaxyTitles = getResources().getStringArray(R.array.items_array);
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
mDrawerList = (ListView) findViewById(R.id.left_drawer);
mDrawerGrid = (GridView)findViewById(R.id.gridview);
mDrawerLinear =(LinearLayout)findViewById(R.id.linearLayout);
mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
mDrawerGrid.setAdapter(new ImageAdapter(MainActivity.this));
mDrawerList.setAdapter(new ArrayAdapter<String>(this,
R.layout.drawer_list_item, mGalaxyTitles));
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().setHomeButtonEnabled(true);
mDrawerToggle = new ActionBarDrawerToggle(
this,
mDrawerLayout,
R.drawable.ic_drawer,
R.string.drawer_open,
R.string.drawer_close
) {
public void onDrawerClosed(View view) {
getActionBar().setTitle(mDrawerTitle);
invalidateOptionsMenu();
}
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle(mDrawerTitle);
invalidateOptionsMenu();
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
if (savedInstanceState == null) {
selectItem(0);
}
}
class DrawerItemClickListener implements ListView.OnItemClickListener {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
// TODO Auto-generated method stub
switch(position){
case 0:
menu0();
return;
case 1:
menu1();
return;
case 2:
menu2();
return;
case 3:
menu3();
return;
case 4:
menu4();
return;
case 5:
menu5();
return;
case 6:
menu6();
return;
case 7:
menu7();
return;
case 8:
menu8();
return;
}
}
protected void menu0() {
Intent Main0 = new Intent(MainActivity.this, Page0.class);
startActivity(Main0);
return;
}
protected void menu1() {
Intent Main1 = new Intent(MainActivity.this, Page1.class);
startActivity(Main1);
return;
}
protected void menu2() {
Intent Main2 = new Intent(MainActivity.this, Page2.class);
startActivity(Main2);
return;
}
protected void menu3() {
Intent Main3 = new Intent(MainActivity.this, Page3.class);
startActivity(Main3);
return;
}
protected void menu4() {
Intent Main4 = new Intent(MainActivity.this, Page4.class);
startActivity(Main4);
return;
}
protected void menu5() {
Intent Main5 = new Intent(MainActivity.this, Page5.class);
startActivity(Main5);
return;
}
protected void menu6() {
Intent Main6 = new Intent(MainActivity.this, Page6.class);
startActivity(Main6);
return;
}
protected void menu7() {
Intent Main7 = new Intent(MainActivity.this, Page7.class);
startActivity(Main7);
return;
}
protected void menu8() {
Intent Main8 = new Intent(MainActivity.this, Page8.class);
startActivity(Main8);
return;
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public void setTitle(CharSequence title) {
mTitle = title;
getActionBar().setTitle(mDrawerTitle);
}
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
//boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
//boolean drawerOpen2 = mDrawerLayout.isDrawerOpen(mDrawerGrid);
boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerLayout);
menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
//menu.findItem(R.id.action_settings).setVisible(!drawerOpen2);
return super.onPrepareOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (mDrawerToggle.onOptionsItemSelected(item)) {
return true;
}
switch(item.getItemId()) {
case R.id.action_settings:
setting();
return true;
case R.id.about:
about();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
private void about() {
// TODO Auto-generated method stub
Intent Main1 = new Intent(MainActivity.this, About.class);
startActivity(Main1);
return;
}
private void setting() {
// TODO Auto-generated method stub
Intent Main1 = new Intent(MainActivity.this, Setting.class);
startActivity(Main1);
return;
}
private void selectItem(int position) {
Fragment fragment = new GalaxyFragment();
Bundle args = new Bundle();
args.putInt(GalaxyFragment.ARG_GALAXY_NUMBER, position);
fragment.setArguments(args);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
mDrawerList.setItemChecked(position, true);
setTitle(mGalaxyTitles[position]);
mDrawerLayout.closeDrawer(mDrawerLayout);
//mDrawerLayout.closeDrawer(mDrawerGrid);
}
class GalaxyFragment extends Fragment{
public static final String ARG_GALAXY_NUMBER = "galaxy_number";
public GalaxyFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.about, container, false);
return rootView;
}
}
//Gridview BaseAdapter class
class ImageAdapter extends BaseAdapter{
Context context;
ImageAdapter(Context context){
this.context = context;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return mThumbIds.length;
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ImageView imageView;
if(convertView == null){
imageView = new ImageView(context);
imageView.setLayoutParams(new GridView.LayoutParams(25, 25));
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
}else {
imageView = (ImageView) convertView;
}
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
// references to our images
private Integer[] mThumbIds = {
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
};
}
}
activity_main.xml
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:id="@+id/drawer_layout">
<FrameLayout
android:id="@+id/content_frame"
android:layout_width="match_parent"
android:layout_height="match_parent" >
</FrameLayout>
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="320dp"
android:layout_height="match_parent"
android:orientation="vertical"
android:layout_gravity="left"
android:choiceMode="singleChoice"
android:divider="@android:color/transparent"
android:dividerHeight="0dp"
android:background="#111">
<GridView
android:id="@+id/gridview"
android:layout_width="280dp"
android:layout_height="match_parent"
android:stretchMode="columnWidth"
android:numColumns="auto_fit"/>
<!-- android:gravity="center" -->
<ListView
android:id="@+id/left_drawer"
android:layout_width="240dp"
android:layout_height="match_parent"
/>
</LinearLayout>
</android.support.v4.widget.DrawerLayout>
日志记录器
07-30 06:15:57.203: W/dalvikvm(853): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
07-30 06:15:57.213: E/AndroidRuntime(853): FATAL EXCEPTION: main
07-30 06:15:57.213: E/AndroidRuntime(853): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.navigationdrawer3/com.example.navigationdrawer3.MainActivity}: java.lang.ClassCastException: android.widget.FrameLayout$LayoutParams cannot be cast to android.support.v4.widget.DrawerLayout$LayoutParams
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.ActivityThread.access$600(ActivityThread.java:141)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.os.Handler.dispatchMessage(Handler.java:99)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.os.Looper.loop(Looper.java:137)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.ActivityThread.main(ActivityThread.java:5041)
07-30 06:15:57.213: E/AndroidRuntime(853): at java.lang.reflect.Method.invokeNative(Native Method)
07-30 06:15:57.213: E/AndroidRuntime(853): at java.lang.reflect.Method.invoke(Method.java:511)
07-30 06:15:57.213: E/AndroidRuntime(853): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
07-30 06:15:57.213: E/AndroidRuntime(853): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
07-30 06:15:57.213: E/AndroidRuntime(853): at dalvik.system.NativeStart.main(Native Method)
07-30 06:15:57.213: E/AndroidRuntime(853): Caused by: java.lang.ClassCastException: android.widget.FrameLayout$LayoutParams cannot be cast to android.support.v4.widget.DrawerLayout$LayoutParams
07-30 06:15:57.213: E/AndroidRuntime(853): at android.support.v4.widget.DrawerLayout.isDrawerView(DrawerLayout.java:809)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.support.v4.widget.DrawerLayout.closeDrawer(DrawerLayout.java:1012)
07-30 06:15:57.213: E/AndroidRuntime(853): at com.example.navigationdrawer3.MainActivity.selectItem(MainActivity.java:265)
07-30 06:15:57.213: E/AndroidRuntime(853): at com.example.navigationdrawer3.MainActivity.onCreate(MainActivity.java:86)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.Activity.performCreate(Activity.java:5104)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
07-30 06:15:57.213: E/AndroidRuntime(853): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
07-30 06:15:57.213: E/AndroidRuntime(853): ... 11 more
第86行的代码:
selectItem(0);
第265行的代码:
mDrawerLayout.closeDrawer(mDrawerLayout);
我已经试过多种方式来纠正这个运行时错误,但一直未能成功。有人可以为我的问题提供建议吗?