Java Toast消息崩溃应用程序
我正在尝试在onCreate之外创建一条toast消息。 这是我的剧本：Java Toast消息崩溃应用程序,java,android,android-activity,toast,Java,Android,Android Activity,Toast,我正在尝试在onCreate之外创建一条toast消息。 这是我的剧本： package com.klh.lehava; import java.io.IOException; import java.lang.reflect.Array; import java.util.Arrays; import java.util.Locale; import org.apache.http.HttpResponse; import org.apache.http.client.ClientProto
package com.klh.lehava;
import java.io.IOException;
import java.lang.reflect.Array;
import java.util.Arrays;
import java.util.Locale;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.protocol.ClientContext;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.cookie.BasicClientCookie;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.util.EntityUtils;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.content.Context;
import android.content.res.Configuration;
import android.os.Bundle;
import android.os.Handler;
import android.provider.Settings.Global;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.CookieManager;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.Toast;
public class MainActivity extends Activity {
static MainActivity MenuChecker = new MainActivity();
private static String response_str;
private static HttpResponse result;
private DrawerLayout mDrawerLayout;
private static ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;
private ArrayAdapter<String> adapter1;
private static String isUserLoggedIn;
public String isUserLoggedIn() {
return isUserLoggedIn;
}
private static String getUrl;
public String getUrl() {
return getUrl;
}
public static final String TAG = "loginCookie";
private CharSequence mDrawerTitle;
private static CharSequence mTitle;
//private final ArrayList<String> assignArr0 = new ArrayList<String>();
private static String[] mPlanetTitles;
private String[] newAr;
@Override
protected void onCreate(Bundle savedInstanceState) {
WebView webview;
webview = (WebView) findViewById(R.id.webview);
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
adapter1 = new ArrayAdapter<String>(this,
R.layout.drawer_list_item, mPlanetTitles);
mDrawerList.setAdapter(adapter1);
mDrawerList.setOnItemClickListener(new DrawerItemClickListener());
// enable ActionBar app icon to behave as action to toggle nav drawer
getActionBar().setDisplayHomeAsUpEnabled(true);
getActionBar().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 */
) {
public void onDrawerClosed(View view) {
getActionBar().setTitle(mTitle);
invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
}
public void onDrawerOpened(View drawerView) {
getActionBar().setTitle(mDrawerTitle);
invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
if (savedInstanceState == null) {
selectItem(0);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
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()) {
default:
return super.onOptionsItemSelected(item);
}
}
/* 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
Bundle args = new Bundle();
if (position == 0)
{
Fragment fragment = new MainFragment();
args.putInt(MainFragment.ARG_PLANET_NUMBER, position);
fragment.setArguments(args);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
mDrawerList.setItemChecked(position, true);
setTitle(mPlanetTitles[position]);
mDrawerLayout.closeDrawer(mDrawerList);
}
if (position == 1)
{
Fragment fragment = new InOutFragment();
args.putInt(InOutFragment.ARG_PLANET_NUMBER, position);
fragment.setArguments(args);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
mDrawerList.setItemChecked(position, true);
setTitle(mPlanetTitles[position]);
mDrawerLayout.closeDrawer(mDrawerList);
}
if (position == 2)
{
Fragment fragment = new AddEventFragment();
args.putInt(AddEventFragment.ARG_PLANET_NUMBER, position);
fragment.setArguments(args);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
mDrawerList.setItemChecked(position, true);
setTitle(mPlanetTitles[position]);
mDrawerLayout.closeDrawer(mDrawerList);
}
if (position == 3)
{
Fragment fragment = new AboutFragment();
args.putInt(AboutFragment.ARG_PLANET_NUMBER, position);
fragment.setArguments(args);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
mDrawerList.setItemChecked(position, true);
setTitle(mPlanetTitles[position]);
mDrawerLayout.closeDrawer(mDrawerList);
}
if (position == 4)
{
Fragment fragment = new WebLogoutFragment();
args.putInt(WebLogoutFragment.ARG_PLANET_NUMBER, position);
fragment.setArguments(args);
FragmentManager fragmentManager = getFragmentManager();
fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();
mDrawerList.setItemChecked(0, true);
setTitle(mPlanetTitles[0]);
mDrawerLayout.closeDrawer(mDrawerList);
}
//isLoggedIn=IsLoggedIn();
// update selected item and title, then close the drawer
}
@Override
public void setTitle(CharSequence title) {
mTitle = title;
getActionBar().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) {
/*TextView textView = (TextView)getActivity(). findViewById(R.id.textView1);
textView.setText("hi");*/
//Toast.makeText(context, positions, duration).show();
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;
}
}
public static class AboutFragment extends Fragment {
public static final String ARG_PLANET_NUMBER = "planet_number";
public AboutFragment() {
// Empty constructor required for fragment subclasses
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_about, 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;
}
}
public static class MainFragment extends Fragment {
public static final String ARG_PLANET_NUMBER = "planet_number";
public static final String MY_DOMAIN = "klh-dev.com";
public MainFragment() {
// Empty constructor required for fragment subclasses
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_web, container, false);
int i = getArguments().getInt(ARG_PLANET_NUMBER);
String planet = getResources().getStringArray(R.array.planets_array)[i];
WebView webview;
webview = (WebView) rootView.findViewById(R.id.webview);
webview.setWebViewClient(new WebViewClient() {
@Override
public void onPageFinished(WebView view, String url) {
String weburl = view.getUrl();
String cookies = CookieManager.getInstance().getCookie(url);
getUrl = view.getUrl();
isUserLoggedIn=IsLoggedIn();
Log.d(TAG, "All the cookies in a string:" + cookies);
if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mlogin.php")) {
mDrawerList.setItemChecked(0, true);
getActivity().getActionBar().setTitle("התחברות");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mtimecounter.php")) {
mDrawerList.setItemChecked(1, true);
getActivity().getActionBar().setTitle("כניסה/יציאה");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/madd.php")) {
mDrawerList.setItemChecked(2, true);
getActivity().getActionBar().setTitle("הוספת אירוע");
}
}
});
webview.getSettings().setJavaScriptEnabled(true);
webview.getSettings().setUseWideViewPort(true);
webview.setWebChromeClient(new WebChromeClient());
webview.loadUrl("http://www.klh-dev.com/lehava/lehava/system/mlogin.php");
getActivity().setTitle(planet);
return rootView;
}
}
public static class InOutFragment extends Fragment {
public static final String ARG_PLANET_NUMBER = "planet_number";
public static final String MY_DOMAIN = "klh-dev.com";
public InOutFragment() {
// Empty constructor required for fragment subclasses
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_web, container, false);
int i = getArguments().getInt(ARG_PLANET_NUMBER);
String planet = getResources().getStringArray(R.array.planets_array)[i];
WebView webview;
webview = (WebView) rootView.findViewById(R.id.webview);
webview.setWebViewClient(new WebViewClient() {
@Override
public void onPageFinished(WebView view, String url) {
String weburl = view.getUrl();
String cookies = CookieManager.getInstance().getCookie(url);
getUrl = view.getUrl();
isUserLoggedIn=IsLoggedIn();
Log.d(TAG, "All the cookies in a string:" + cookies);
if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mlogin.php")) {
mDrawerList.setItemChecked(0, true);
getActivity().getActionBar().setTitle("התחברות");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mtimecounter.php")) {
mDrawerList.setItemChecked(1, true);
getActivity().getActionBar().setTitle("כניסה/יציאה");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/madd.php")) {
mDrawerList.setItemChecked(2, true);
getActivity().getActionBar().setTitle("הוספת אירוע");
}
}
});
webview.getSettings().setJavaScriptEnabled(true);
webview.getSettings().setUseWideViewPort(true);
webview.setWebChromeClient(new WebChromeClient());
webview.loadUrl("http://www.klh-dev.com/lehava/lehava/system/mtimecounter.php");
getActivity().setTitle(planet);
return rootView;
}
}
public static class AddEventFragment extends Fragment {
public static final String ARG_PLANET_NUMBER = "planet_number";
public static final String MY_DOMAIN = "klh-dev.com";
public AddEventFragment() {
// Empty constructor required for fragment subclasses
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_web, container, false);
int i = getArguments().getInt(ARG_PLANET_NUMBER);
String planet = getResources().getStringArray(R.array.planets_array)[i];
WebView webview;
webview = (WebView) rootView.findViewById(R.id.webview);
webview.setWebViewClient(new WebViewClient() {
@Override
public void onPageFinished(WebView view, String url) {
String weburl = view.getUrl();
String cookies = CookieManager.getInstance().getCookie(url);
getUrl = view.getUrl();
isUserLoggedIn=IsLoggedIn();
Log.d(TAG, "All the cookies in a string:" + cookies);
if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mlogin.php")) {
mDrawerList.setItemChecked(0, true);
getActivity().getActionBar().setTitle("התחברות");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mtimecounter.php")) {
mDrawerList.setItemChecked(1, true);
getActivity().getActionBar().setTitle("כניסה/יציאה");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/madd.php")) {
mDrawerList.setItemChecked(2, true);
getActivity().getActionBar().setTitle("הוספת אירוע");
}
}
});
webview.getSettings().setJavaScriptEnabled(true);
webview.getSettings().setUseWideViewPort(true);
webview.setWebChromeClient(new WebChromeClient());
webview.loadUrl("http://www.klh-dev.com/lehava/lehava/system/madd.php");
getActivity().setTitle(planet);
return rootView;
}
}
public static class WebLogoutFragment extends Fragment {
public static final String ARG_PLANET_NUMBER = "planet_number";
public WebLogoutFragment() {
// Empty constructor required for fragment subclasses
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_web, container, false);
WebView webview;
webview = (WebView) rootView.findViewById(R.id.webview);
webview.setWebViewClient(new WebViewClient() {
@Override
public void onPageFinished(WebView view, String url) {
String weburl = view.getUrl();
String cookies = CookieManager.getInstance().getCookie(url);
getUrl = view.getUrl();
isUserLoggedIn=IsLoggedIn();
Log.d(TAG, "All the cookies in a string:" + cookies);
if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mlogin.php")) {
mDrawerList.setItemChecked(0, true);
getActivity().getActionBar().setTitle("התחברות");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mlogin.php?log=1")) {
mDrawerList.setItemChecked(0, true);
getActivity().getActionBar().setTitle("התחברות");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mtimecounter.php")) {
mDrawerList.setItemChecked(1, true);
getActivity().getActionBar().setTitle("כניסה/יציאה");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/madd.php")) {
mDrawerList.setItemChecked(2, true);
getActivity().getActionBar().setTitle("הוספת אירוע");
} else if (weburl.equals("http://www.klh-dev.com/lehava/lehava/system/mlogin.php?log=1")) {
mDrawerList.setItemChecked(2, true);
getActivity().getActionBar().setTitle("התחברות");
}
}
});
webview.getSettings().setJavaScriptEnabled(true);
webview.getSettings().setUseWideViewPort(true);
webview.setWebChromeClient(new WebChromeClient());
webview.loadUrl("http://www.klh-dev.com/lehava/lehava/system/mlogout.php");
return rootView;
}
}
public static BasicCookieStore getCookieStore(String cookies, String domain) {
String[] cookieValues = cookies.split(";");
BasicCookieStore cs = new BasicCookieStore();
BasicClientCookie cookie;
for (int i = 0; i < cookieValues.length; i++) {
String[] split = cookieValues[i].split("=");
if (split.length == 2)
cookie = new BasicClientCookie(split[0], split[1]);
else
cookie = new BasicClientCookie(split[0], null);
cookie.setDomain(domain);
cs.addCookie(cookie);
}
return cs;
}
02-01 14:41:50.976: E/AndroidRuntime(25010): FATAL EXCEPTION: main
02-01 14:41:50.976: E/AndroidRuntime(25010): Process: com.klh.lehava, PID: 25010
02-01 14:41:50.976: E/AndroidRuntime(25010): java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference
02-01 14:41:50.976: E/AndroidRuntime(25010): at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:105)
02-01 14:41:50.976: E/AndroidRuntime(25010): at com.klh.lehava.MainActivity$3.run(MainActivity.java:663)
02-01 14:41:50.976: E/AndroidRuntime(25010): at android.os.Handler.handleCallback(Handler.java:739)
02-01 14:41:50.976: E/AndroidRuntime(25010): at android.os.Handler.dispatchMessage(Handler.java:95)
02-01 14:41:50.976: E/AndroidRuntime(25010): at android.os.Looper.loop(Looper.java:135)
02-01 14:41:50.976: E/AndroidRuntime(25010): at android.app.ActivityThread.main(ActivityThread.java:5221)
02-01 14:41:50.976: E/AndroidRuntime(25010): at java.lang.reflect.Method.invoke(Native Method)
02-01 14:41:50.976: E/AndroidRuntime(25010): at java.lang.reflect.Method.invoke(Method.java:372)
02-01 14:41:50.976: E/AndroidRuntime(25010): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
02-01 14:41:50.976: E/AndroidRuntime(25010): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
}
public void showToast(final String toast)
{
public static String IsLoggedIn() {
new Thread(new Runnable() {
@Override
public void run() {
String cookies = CookieManager.getInstance().getCookie(getUrl);
BasicCookieStore lCS = getCookieStore(cookies, "klh-dev.com");
HttpContext localContext = new BasicHttpContext();
DefaultHttpClient httpclient = new DefaultHttpClient();
httpclient.setCookieStore(lCS);
localContext.setAttribute(ClientContext.COOKIE_STORE, lCS);
HttpGet get = new HttpGet("http://klh-dev.com/lehava/lehava/system/isloggedin.php");
try {
result=httpclient.execute(get,localContext);
response_str = EntityUtils.toString(result.getEntity());
System.out.println(response_str);
MenuChecker.UpdateMenu();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
return response_str;
}
static MainActivity MenuChecker = new MainActivity();
新建实例化活动。它们对任何你会使用活动
的东西都没有任何好处，例如作为上下文
相反，将上下文作为参数传递给需要它的方法。使用此方法解决：
Execute runOnUiThread method using activity like
this.runOnUiThread(new Runnable()
{
public void run()
{
Toast.makeText(MainActivity.this, toast, Toast.LENGTH_SHORT).show();
}
});
OR
Activity activity = // reference to an Activity
activity.runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(activity, toast, Toast.LENGTH_SHORT).show();
}
});
private static MainActivity instance;
public MainActivity() {
instance = this;
}
并将showtoast脚本更改为：
Toast.makeText(instance, toast, Toast.LENGTH_SHORT).show();
如果希望在UI线程上运行新线程，则不需要新线程。另外，您确定mPlanetTitles[1]不为空吗？请尝试getapplicationcontext而不是MainActivity。这是MainActivity中的行号663
是什么？rununuithread（new Runnable（）
？为什么要这样做？您是否试图从AsyncTask
显示Toast
？@barq即使运行showToast，我也会收到相同的错误(“嗨”）；但我需要这行代码才能从IsLoggedIn运行UpdateMenu。还有其他方法吗？如果不想传递上下文
参数或使用正确初始化为上下文
的对象，可以删除所有需要有效上下文的调用，例如toasts。我如何正确传递上下文？我做到了尝试几次，但都不起作用，或者根本解决不了问题。。
Toast.makeText(instance, toast, Toast.LENGTH_SHORT).show();