我正在尝试在导航抽屉中添加图像，我将它放在48 * 48大小的drawable文件夹中，我的字符串数组字符串数组在string.xml中，
我遵循了一个教程，但最后我做的更改崩溃了我的应用程序我无法弄清楚问题是什么以及如何解决？
这是例外
01-23 19:32:41.277: E/AndroidRuntime(16889): java.lang.NullPointerException
01-23 19:32:41.277: E/AndroidRuntime(16889): at com.pKLabs.RgpvDigest.MyAdapter.getView(MainActivity.java:339)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.AbsListView.obtainView(AbsListView.java:2733)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.ListView.makeAndAddView(ListView.java:1811)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.ListView.fillDown(ListView.java:697)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.ListView.fillFromTop(ListView.java:763)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.ListView.layoutChildren(ListView.java:1641)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.AbsListView.onLayout(AbsListView.java:2546)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.View.layout(View.java:15664)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewGroup.layout(ViewGroup.java:4869)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.support.v4.widget.DrawerLayout.onLayout(DrawerLayout.java:914)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.View.layout(View.java:15664)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewGroup.layout(ViewGroup.java:4869)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.FrameLayout.layoutChildren(FrameLayout.java:453)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.FrameLayout.onLayout(FrameLayout.java:388)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.View.layout(View.java:15664)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewGroup.layout(ViewGroup.java:4869)
01-23 19:32:41.277: E/AndroidRuntime(16889): at com.android.internal.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.java:429)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.View.layout(View.java:15664)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewGroup.layout(ViewGroup.java:4869)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.FrameLayout.layoutChildren(FrameLayout.java:453)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.widget.FrameLayout.onLayout(FrameLayout.java:388)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.View.layout(View.java:15664)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewGroup.layout(ViewGroup.java:4869)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2246)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1968)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1200)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6401)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:803)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.Choreographer.doCallbacks(Choreographer.java:603)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.Choreographer.doFrame(Choreographer.java:573)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:789)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.os.Handler.handleCallback(Handler.java:733)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.os.Handler.dispatchMessage(Handler.java:95)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.os.Looper.loop(Looper.java:157)
01-23 19:32:41.277: E/AndroidRuntime(16889): at android.app.ActivityThread.main(ActivityThread.java:5335)
01-23 19:32:41.277: E/AndroidRuntime(16889): at java.lang.reflect.Method.invokeNative(Native Method)
01-23 19:32:41.277: E/AndroidRuntime(16889): at java.lang.reflect.Method.invoke(Method.java:515)
01-23 19:32:41.277: E/AndroidRuntime(16889): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
01-23 19:32:41.277: E/AndroidRuntime(16889): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
01-23 19:32:41.277: E/AndroidRuntime(16889): at dalvik.system.NativeStart.main(Native Method)
MainActivity
public class MainActivity extends ActionBarActivity implements
OnItemClickListener {
private DrawerLayout drawerLayout;
private ListView listView;
// private String[] navdra;
private ActionBarDrawerToggle drawerListner;
private MyAdapter myAdapter;
Intent shareintent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// navdra = getResources().getStringArray(R.array.navdra);
listView = (ListView) findViewById(R.id.drawerlist);
myAdapter = new MyAdapter(this);
// listView.setAdapter(new ArrayAdapter<String>(this,
// android.R.layout.simple_expandable_list_item_1, navdra));
listView.setAdapter(myAdapter);
listView.setOnItemClickListener(this);
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
drawerListner = new ActionBarDrawerToggle(this, drawerLayout,
R.drawable.ic_drawer, R.string.dopen, R.string.dclose);
/*
* @Override public void onDrawerOpened(View drawerView) {
* Toast.makeText(MainActivity.this, "Open", Toast.LENGTH_SHORT)
* .show(); }
*
* @Override public void onDrawerClosed(View drawerView) {
* Toast.makeText(MainActivity.this, "Close", Toast.LENGTH_SHORT)
* .show(); } }
*/
drawerLayout.setDrawerListener(drawerListner);
getSupportActionBar().setHomeButtonEnabled(true);
getActionBar().setDisplayHomeAsUpEnabled(true);
Button csv = (Button) findViewById(R.id.cs);
csv.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(v.getContext(), Semester.class);
startActivityForResult(intent, 0);
}
});
Button cal = (Button) findViewById(R.id.cal);
cal.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(v.getContext(), Calculator.class);
startActivityForResult(intent, 0);
}
});
Button iq = (Button) findViewById(R.id.interviewquestion);
iq.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(v.getContext(),
InterviewQuestion.class);
startActivityForResult(intent, 0);
}
});
Button cg = (Button) findViewById(R.id.program);
cg.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(v.getContext(), Programs.class);
startActivityForResult(intent, 0);
}
});
Button abt = (Button) findViewById(R.id.about);
abt.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "PKlabs!!!",
Toast.LENGTH_SHORT).show();
// Intent intent = new Intent
// (v.getContext(),InterviewQuestion.class);
// startActivityForResult(intent,0);
}
});
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
// TODO Auto-generated method stub
super.onConfigurationChanged(newConfig);
drawerListner.onConfigurationChanged(newConfig);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onPostCreate(savedInstanceState);
drawerListner.syncState();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuItem item = menu.add("share"); // your desired title here
item.setIcon(R.drawable.share_icon); // your desired icon here
item.setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
item.setOnMenuItemClickListener(new OnMenuItemClickListener() {
@Override
public boolean onMenuItemClick(MenuItem item) {
shareintent = new Intent(android.content.Intent.ACTION_SEND);
shareintent.setType("text/plain");
String shareBody = "Here is the share content body";
shareintent.putExtra(android.content.Intent.EXTRA_SUBJECT,
"Subject Here");
shareintent.putExtra(Intent.EXTRA_TEXT, "Hi there");
startActivity(Intent.createChooser(shareintent, "Share via"));
return true;
}
});
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
if (drawerListner.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
if (position == 0) {
Uri uri = Uri
.parse("https://2ce74af0d8de8783b91cdd315eeba0340a4b9277.googledrive.com/host/0B2sDUzNeIK0KODB0ZDRMVjFPaFE/Jobs.html");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
} else if (position == 1) {
Intent intent = new Intent(this, Careerguid.class);
startActivityForResult(intent, 0);
} else if (position == 2) {
Toast.makeText(this, "Coming Soon!!!", Toast.LENGTH_LONG).show();
}
// }
else if (position == 3) {
Uri uri = Uri.parse("http://www.google.com");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
else if (position == 4) {
Intent intent = new Intent(Intent.ACTION_SEND);
intent.setType("plain/text");
final PackageManager pm = getPackageManager();
final List<ResolveInfo> matches = pm.queryIntentActivities(intent,
0);
ResolveInfo best = null;
for (final ResolveInfo info : matches)
if (info.activityInfo.packageName.endsWith(".gm")
|| info.activityInfo.name.toLowerCase().contains(
"gmail"))
best = info;
if (best != null)
intent.setClassName(best.activityInfo.packageName,
best.activityInfo.name);
intent.putExtra(Intent.EXTRA_EMAIL,
new String[] { "laboratorypk@gmail.com" });
intent.putExtra(Intent.EXTRA_SUBJECT, "Query/Feedback");
intent.putExtra(Intent.EXTRA_TEXT, "");
startActivity(Intent.createChooser(intent, ""));
}
if (position == 5) {
Intent intent = new Intent(Intent.ACTION_SEND);
intent.setType("plain/text");
final PackageManager pm = getPackageManager();
final List<ResolveInfo> matches = pm.queryIntentActivities(intent,
0);
ResolveInfo best = null;
for (final ResolveInfo info : matches)
if (info.activityInfo.packageName.endsWith(".gm")
|| info.activityInfo.name.toLowerCase().contains(
"gmail"))
best = info;
if (best != null)
intent.setClassName(best.activityInfo.packageName,
best.activityInfo.name);
intent.putExtra(Intent.EXTRA_EMAIL,
new String[] { "laboratorypk@gmail.com" });
intent.putExtra(Intent.EXTRA_SUBJECT, "PC Games");
intent.putExtra(Intent.EXTRA_TEXT,
"Hey! I need PC Games pls share the List.");
startActivity(Intent.createChooser(intent, ""));
}
drawerLayout.closeDrawers();
selectItem(position);
}
public void selectItem(int position) {
// TODO Auto-generated method stub
listView.setItemChecked(position, true);
}
public void setTitle(String title) {
getSupportActionBar().setTitle(title);
}
private Toast toast;
private long lastBackPressTime = 0;
@Override
public void onBackPressed() {
if (this.lastBackPressTime < System.currentTimeMillis() - 4000) {
toast = Toast.makeText(this, "Press back again to exit",
Toast.LENGTH_LONG);
toast.show();
this.lastBackPressTime = System.currentTimeMillis();
drawerLayout.closeDrawers();
} else {
if (toast != null) {
toast.cancel();
}
super.onBackPressed();
}
}
}
class MyAdapter extends BaseAdapter {
private Context context;
String[] navlist;
int[] images = { R.drawable.job, R.drawable.career, R.drawable.project,
R.drawable.facebook, R.drawable.mail, R.drawable.games };
public MyAdapter(Context context) {
this.context = context;
navlist = context.getResources().getStringArray(R.array.navdra);
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return navlist.length;
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return navlist[position];
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = null;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
inflater.inflate(R.layout.customrow, parent, false);
}
else {
row = convertView;
}
TextView titleTextView = (TextView) row.findViewById(R.id.textView11);
ImageView titleImageView = (ImageView) row
.findViewById(R.id.imageView1);
titleTextView.setText(navlist[position]);
titleImageView.setImageResource(images[position]);
return row;
}
}
customrow.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_weight="1"
android:layout_height="wrap_content"
/>
<TextView
android:layout_margin="8dp"
android:id="@+id/textView11"
android:layout_width="wrap_content"
android:layout_weight="1"
android:layout_height="wrap_content"
android:gravity="center"
/>
</LinearLayout>
答案 0 :(得分：2)
row为null，将inflate的返回值赋给行变量。
row = inflater.inflate(R.layout.customrow, parent, false);
答案 1 :(得分：1)
只需复制并粘贴即可。
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// navdra = getResources().getStringArray(R.array.navdra);
listView = (ListView) findViewById(R.id.drawerlist);
myAdapter = new MyAdapter(this);
// listView.setAdapter(new ArrayAdapter<String>(this,
// android.R.layout.simple_expandable_list_item_1, navdra));
listView.setAdapter(myAdapter);
listView.setOnItemClickListener(this);
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
drawerListner = new ActionBarDrawerToggle(this, drawerLayout,
R.drawable.ic_drawer, R.string.dopen, R.string.dclose);
/*
* @Override public void onDrawerOpened(View drawerView) {
* Toast.makeText(MainActivity.this, "Open", Toast.LENGTH_SHORT)
* .show(); }
*
* @Override public void onDrawerClosed(View drawerView) {
* Toast.makeText(MainActivity.this, "Close", Toast.LENGTH_SHORT)
* .show(); } }
*/
drawerLayout.setDrawerListener(drawerListner);
getSupportActionBar().setHomeButtonEnabled(true);
getActionBar().setDisplayHomeAsUpEnabled(true);
Button csv = (Button) findViewById(R.id.cs);
csv.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(v.getContext(), Semester.class);
startActivityForResult(intent, 0);
}
});
Button cal = (Button) findViewById(R.id.cal);
cal.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(v.getContext(), Calculator.class);
startActivityForResult(intent, 0);
}
});
Button iq = (Button) findViewById(R.id.interviewquestion);
iq.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(v.getContext(),
InterviewQuestion.class);
startActivityForResult(intent, 0);
}
});
Button cg = (Button) findViewById(R.id.program);
cg.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(v.getContext(), Programs.class);
startActivityForResult(intent, 0);
}
});
Button abt = (Button) findViewById(R.id.about);
abt.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "PKlabs!!!",
Toast.LENGTH_SHORT).show();
// Intent intent = new Intent
// (v.getContext(),InterviewQuestion.class);
// startActivityForResult(intent,0);
}
});
}
@Override
public void onConfigurationChanged(Configuration newConfig) {
// TODO Auto-generated method stub
super.onConfigurationChanged(newConfig);
drawerListner.onConfigurationChanged(newConfig);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onPostCreate(savedInstanceState);
drawerListner.syncState();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuItem item = menu.add("share"); // your desired title here
item.setIcon(R.drawable.share_icon); // your desired icon here
item.setShowAsAction(MenuItem.SHOW_AS_ACTION_ALWAYS);
item.setOnMenuItemClickListener(new OnMenuItemClickListener() {
@Override
public boolean onMenuItemClick(MenuItem item) {
shareintent = new Intent(android.content.Intent.ACTION_SEND);
shareintent.setType("text/plain");
String shareBody = "Here is the share content body";
shareintent.putExtra(android.content.Intent.EXTRA_SUBJECT,
"Subject Here");
shareintent.putExtra(Intent.EXTRA_TEXT, "Hi there");
startActivity(Intent.createChooser(shareintent, "Share via"));
return true;
}
});
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
if (drawerListner.onOptionsItemSelected(item)) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
if (position == 0) {
Uri uri = Uri
.parse("https://2ce74af0d8de8783b91cdd315eeba0340a4b9277.googledrive.com/host/0B2sDUzNeIK0KODB0ZDRMVjFPaFE/Jobs.html");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
} else if (position == 1) {
Intent intent = new Intent(this, Careerguid.class);
startActivityForResult(intent, 0);
} else if (position == 2) {
Toast.makeText(this, "Coming Soon!!!", Toast.LENGTH_LONG).show();
}
// }
else if (position == 3) {
Uri uri = Uri.parse("http://www.google.com");
Intent intent = new Intent(Intent.ACTION_VIEW, uri);
startActivity(intent);
}
else if (position == 4) {
Intent intent = new Intent(Intent.ACTION_SEND);
intent.setType("plain/text");
final PackageManager pm = getPackageManager();
final List<ResolveInfo> matches = pm.queryIntentActivities(intent,
0);
ResolveInfo best = null;
for (final ResolveInfo info : matches)
if (info.activityInfo.packageName.endsWith(".gm")
|| info.activityInfo.name.toLowerCase().contains(
"gmail"))
best = info;
if (best != null)
intent.setClassName(best.activityInfo.packageName,
best.activityInfo.name);
intent.putExtra(Intent.EXTRA_EMAIL,
new String[] { "laboratorypk@gmail.com" });
intent.putExtra(Intent.EXTRA_SUBJECT, "Query/Feedback");
intent.putExtra(Intent.EXTRA_TEXT, "");
startActivity(Intent.createChooser(intent, ""));
}
if (position == 5) {
Intent intent = new Intent(Intent.ACTION_SEND);
intent.setType("plain/text");
final PackageManager pm = getPackageManager();
final List<ResolveInfo> matches = pm.queryIntentActivities(intent,
0);
ResolveInfo best = null;
for (final ResolveInfo info : matches)
if (info.activityInfo.packageName.endsWith(".gm")
|| info.activityInfo.name.toLowerCase().contains(
"gmail"))
best = info;
if (best != null)
intent.setClassName(best.activityInfo.packageName,
best.activityInfo.name);
intent.putExtra(Intent.EXTRA_EMAIL,
new String[] { "laboratorypk@gmail.com" });
intent.putExtra(Intent.EXTRA_SUBJECT, "PC Games");
intent.putExtra(Intent.EXTRA_TEXT,
"Hey! I need PC Games pls share the List.");
startActivity(Intent.createChooser(intent, ""));
}
drawerLayout.closeDrawers();
selectItem(position);
}
public void selectItem(int position) {
// TODO Auto-generated method stub
listView.setItemChecked(position, true);
}
public void setTitle(String title) {
getSupportActionBar().setTitle(title);
}
private Toast toast;
private long lastBackPressTime = 0;
@Override
public void onBackPressed() {
if (this.lastBackPressTime < System.currentTimeMillis() - 4000) {
toast = Toast.makeText(this, "Press back again to exit",
Toast.LENGTH_LONG);
toast.show();
this.lastBackPressTime = System.currentTimeMillis();
drawerLayout.closeDrawers();
} else {
if (toast != null) {
toast.cancel();
}
super.onBackPressed();
}
}
}
class MyAdapter extends BaseAdapter {
private Context context;
String[] navlist;
int[] images = { R.drawable.job, R.drawable.career, R.drawable.project,
R.drawable.facebook, R.drawable.mail, R.drawable.games };
public MyAdapter(Context context) {
this.context = context;
navlist = context.getResources().getStringArray(R.array.navdra);
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return navlist.length;
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return navlist[position];
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = null;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.customrow, parent, false);
}
else {
row = convertView;
}
TextView titleTextView = (TextView) row.findViewById(R.id.textView11);
ImageView titleImageView = (ImageView) row
.findViewById(R.id.imageView1);
titleTextView.setText(navlist[position]);
titleImageView.setImageResource(images[position]);
return row;
}
}