android可以从任何地方获取应用程序上下文，但它总是显示类cast exeption，我不知道如何使用它 我只是从网络上获取引用并在android中更新代码。这意味着从任何地方获取应用程序上下文。但它总是显示类cast exeption，我不知道如何在
android可以从任何地方获取应用程序上下文，但它总是显示类cast exeption，我不知道如何使用它android可以从任何地方获取应用程序上下文，但它总是显示类cast exeption，我不知道如何使用它 我只是从网络上获取引用并在android中更新代码。这意味着从任何地方获取应用程序上下文。但它总是显示类cast exeption，我不知道如何在,android,Android,android可以从任何地方获取应用程序上下文，但它总是显示类cast exeption，我不知道如何使用它 我只是从网络上获取引用并在android中更新代码。这意味着从任何地方获取应用程序上下文。但它总是显示类cast exeption，我不知道如何在适配器/活动中使用，片段 请任何知道这一点的人分享你的观点/想法 Applicationcontext.java 包com.example.admin.myapplication； 导入android.app.Application； 导入an
我只是从网络上获取引用并在android中更新代码。这意味着从任何地方获取应用程序上下文。但它总是显示类cast exeption，我不知道如何在适配器/活动中使用，片段
请任何知道这一点的人分享你的观点/想法
Applicationcontext.java
包com.example.admin.myapplication；
导入android.app.Application；
导入android.content.Context；
导入com.example.admin.myapplication.models.ParsedApplication设置；
公共类ApplicationContext扩展应用程序{
/**
*解析XML文件后获得的设置
*/
public ParsedApplicationSettings mParsedApplicationSettings=null；
私有静态语境；
公共ParsedApplication设置GetParsedApplication设置（）{
返回mParsedApplicationSettings；
}
/**
*ParsedApplication设置的Setter
*
*@param parsedApplicationSettings
*要为applicationContext设置的已解析XML设置；
*/
公共void setParsedApplication设置(
ParsedApplicationSettings（ParsedApplicationSettings）{
this.mParsedApplicationSettings=parsedApplicationSettings；
}
}
Mainactivity.java
基本上在这个活动中，我有一个导航抽屉。我将整个应用程序上下文用于单个状态类。但每当我使用该应用程序上下文时，总是显示classcast异常，nullpointer Execution
包com.example.admin.myapplication.fragments；
我使用从网络上获取的代码，我对android deep没有太多的了解
基本上在这个活动中，我有一个导航抽屉。我将整个应用程序上下文用于单个状态类。但每当我使用该应用程序上下文时，总是显示classcast异常，nullpointer Execution
包com.example.admin.myapplication.fragments；
我使用从网络上获取的代码，我对android deep没有太多的了解
…对不起，英语不好
导入android.app.Activity；
导入android.content.Context；
导入android.os.Bundle；
导入android.support.v4.app.Fragment；
导入android.support.v4.view.ViewPager；
导入android.view.LayoutInflater；
导入android.view.view；
导入android.view.ViewGroup；
导入android.widget.ImageView；
导入android.widget.RelativeLayout；
导入com.example.admin.myapplication.ApplicationContext；
导入com.example.admin.myapplication.main活动；
导入com.example.admin.myapplication.R；
导入com.example.admin.myapplication.adapters.HomeFragmentViewPagerAdapter；
导入com.example.admin.myapplication.models.MainPageSettings；
公共类HomeFragment扩展了片段{
公共静态最终字符串标记=HomeFragment.class.getSimpleName（）；
公共接口ActionListener{
void onReservationButtonClicked（）；
void onRatesButtonClicked（）；
void onGalleryButtonClicked（）；
void onRoomsButtonClicked（）；
设备按钮无效勾选（）；
void onLocationButtonClicked（）；
}
私有android.support.v4.view.ViewPager mViewPager；
私有相对物Yout mReservationButton；
私人相对人按钮；
私有相对物激活mGalleryButton；
私人相对人yout mRoomsButton；
私有相对物Yout mFacilities按钮；
私密的相对位置按钮；
私有ActionListener；
私有应用程序上下文mAppContext=新应用程序上下文（）；
公共HomeFragment（）{
超级（）；
}
公共静态HomeFragment newInstance（ApplicationContext appContext，
ActionListener（ActionListener）{
if（actionListener==null）{
抛出新的IllegalArgumentException（ActionListener.class.getName（）
+“是空的！”）；
}
HomeFragment=新的HomeFragment（）；
fragment.mActionListener=actionListener；
fragment.mAppContext=appContext；
返回片段；
}
@凌驾
公共事务主任（活动）{
超级转速计（活动）；
}
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
}
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、，
Bundle savedInstanceState）{
视图=充气机。充气（R.layout.fragment_main，容器，假）；
mViewPager=（ViewPager）view.findViewById（R.id.mainFragmentViewPager）；
MainPageSettings MainPageSettings=mAppContext
.getParsedApplicationSettings（）.getMainPageSettings（）；
HomeFragmentViewPagerAdapter适配器=新的HomeFragmentViewPagerAdapter(
mAppContext，mainPageSettings.getMainPreviewPictures（））；
mViewPager.setAdapter（适配器）；
//
//CirclePageIndicator circleIndicator=（CirclePageIndicator）视图
//.findViewById（R.id.mainFragmentViewPagerBullets）；
//circleIndicator.setRadius（MainActivity.dipsToPixels（mAppContext，8））；
//circleIndicator.setViewPager（mViewPager）；
ImageView rightButton=（ImageView）视图
.findViewById（R.id.mainFragmentViewPagerRightButton）；
setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
如果（mViewPager.getAdapter（）！=null
&&mViewPager.getAdap
i just get references from net and update code in android.means get application context from anywhere.but its always show class cast exeption i dont knoew how to use in adapter/activity,fragments
please anyone know about this share your view/thoughts
Applicationcontext.java
package com.example.admin.myapplication;
import android.app.Application;
import android.content.Context;
import com.example.admin.myapplication.models.ParsedApplicationSettings;
public class ApplicationContext extends Application {
/**
* The settings obtained after parsing the XML file
*/
public ParsedApplicationSettings mParsedApplicationSettings = null;
private static Context context;
public ParsedApplicationSettings getParsedApplicationSettings() {
return mParsedApplicationSettings;
}
/**
* Setter for ParsedApplicationSettings
*
* @param parsedApplicationSettings
* the parsed XML settings to set for the applicationContext;
*/
public void setParsedApplicationSettings(
ParsedApplicationSettings parsedApplicationSettings) {
this.mParsedApplicationSettings = parsedApplicationSettings;
}
}
Mainactivity.java
basically in this activity i have implement navigation drawer. i used entire application context to single state class.but whenever i use that application context always show classcast exception,nullpointer execption
package com.example.admin.myapplication.fragments;
i use get this code from net and i dont have 2 much knoewlage about android deep
basically in this activity i have implement navigation drawer. i used entire application context to single state class.but whenever i use that application context always show classcast exception,nullpointer execption
package com.example.admin.myapplication.fragments;
i use get this code from net and i dont have 2 much knoewlage about android deep
...sorry for poor english
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import com.example.admin.myapplication.ApplicationContext;
import com.example.admin.myapplication.MainActivity;
import com.example.admin.myapplication.R;
import com.example.admin.myapplication.adapters.HomeFragmentViewPagerAdapter;
import com.example.admin.myapplication.models.MainPageSettings;
public class HomeFragment extends Fragment {
public static final String TAG = HomeFragment.class.getSimpleName();
public interface ActionListener {
void onReservationButtonClicked();
void onRatesButtonClicked();
void onGalleryButtonClicked();
void onRoomsButtonClicked();
void onFacilitiesButtonClicked();
void onLocationsButtonClicked();
}
private android.support.v4.view.ViewPager mViewPager;
private RelativeLayout mReservationButton;
private RelativeLayout mRatesButton;
private RelativeLayout mGalleryButton;
private RelativeLayout mRoomsButton;
private RelativeLayout mFacilitiesButton;
private RelativeLayout mLocationsButton;
private ActionListener mActionListener;
private ApplicationContext mAppContext=new ApplicationContext();
public HomeFragment() {
super();
}
public static HomeFragment newInstance(ApplicationContext appContext,
ActionListener actionListener) {
if (actionListener == null) {
throw new IllegalArgumentException(ActionListener.class.getName()
+ " is null!");
}
HomeFragment fragment = new HomeFragment();
fragment.mActionListener = actionListener;
fragment.mAppContext = appContext;
return fragment;
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_main, container, false);
mViewPager = (ViewPager) view.findViewById(R.id.mainFragmentViewPager);
MainPageSettings mainPageSettings = mAppContext
.getParsedApplicationSettings().getMainPageSettings();
HomeFragmentViewPagerAdapter adapter = new HomeFragmentViewPagerAdapter(
mAppContext, mainPageSettings.getMainPreviewPictures());
mViewPager.setAdapter(adapter);
//
// CirclePageIndicator circleIndicator = (CirclePageIndicator) view
// .findViewById(R.id.mainFragmentViewPagerBullets);
// circleIndicator.setRadius(MainActivity.dipsToPixels(mAppContext, 8));
// circleIndicator.setViewPager(mViewPager);
ImageView rightButton = (ImageView) view
.findViewById(R.id.mainFragmentViewPagerRightButton);
rightButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mViewPager.getAdapter() != null
&& mViewPager.getAdapter().getCount() > mViewPager
.getCurrentItem()) {
mViewPager.setCurrentItem(mViewPager.getCurrentItem() + 1);
}
}
});
ImageView leftButton = (ImageView) view
.findViewById(R.id.mainFragmentViewPagerLeftButton);
leftButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mViewPager.getAdapter() != null
&& mViewPager.getCurrentItem() > 0) {
mViewPager.setCurrentItem(mViewPager.getCurrentItem() - 1);
}
}
});
if (mViewPager.getAdapter() != null
&& mViewPager.getAdapter().getCount() < 2) {
leftButton.setVisibility(View.GONE);
rightButton.setVisibility(View.GONE);
} else {
leftButton.setVisibility(View.VISIBLE);
rightButton.setVisibility(View.VISIBLE);
}
mReservationButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerFirstRowReservationButton);
mReservationButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onReservationButtonClicked();
}
});
mRoomsButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerFirstRowRoomsButton);
mRoomsButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onRoomsButtonClicked();
}
});
mRatesButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerSecondRowRatesButton);
mRatesButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onRatesButtonClicked();
}
});
mFacilitiesButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerSecondRowFacilitiesButton);
mFacilitiesButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onFacilitiesButtonClicked();
}
});
mGalleryButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerThirdRowGalleryButton);
mGalleryButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onGalleryButtonClicked();
}
});
mLocationsButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerThirdRowLocationsButton);
mLocationsButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onLocationsButtonClicked();
}
});
return view;
}
}
locat
this module showing error of code that is occuring after execution of application
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.admin.myapplication/com.example.admin.myapplication.MainActivity}: java.lang.ClassCastException: android.app.Application cannot be cast to com.example.admin.myapplication.ApplicationContext
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.ClassCastException: android.app.Application cannot be cast to com.example.admin.myapplication.ApplicationContext
at com.example.admin.myapplication.MainActivity.onCreate(MainActivity.java:70)
at android.app.Activity.performCreate(Activity.java:5933)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Home_fragment.java(fragment)
this is the first fragment of slider menu which is showing on the top viewpager and in bottom menus(rooms,reservation.....).viewpager slide images whenever user click on menus show particular fragment
all menus are fragments,
public static final String TAG = HomeFragment.class.getSimpleName();
public interface ActionListener {
void onReservationButtonClicked();
void onRatesButtonClicked();
void onGalleryButtonClicked();
void onRoomsButtonClicked();
void onFacilitiesButtonClicked();
void onLocationsButtonClicked();
}
private android.support.v4.view.ViewPager mViewPager;
private RelativeLayout mReservationButton;
private RelativeLayout mRatesButton;
private RelativeLayout mGalleryButton;
private RelativeLayout mRoomsButton;
private RelativeLayout mFacilitiesButton;
private RelativeLayout mLocationsButton;
private ActionListener mActionListener;
private ApplicationContext mAppContext;
public HomeFragment() {
super();
}
public static HomeFragment newInstance(ApplicationContext appContext,
ActionListener actionListener) {
if (actionListener == null)
{
throw new IllegalArgumentException(ActionListener.class.getName()
+ " is null!");
}
HomeFragment fragment = new HomeFragment();
fragment.mActionListener = actionListener;
fragment.mAppContext = appContext;
return fragment;
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
View view = inflater.inflate(R.layout.fragment_main, container, false);
mViewPager = (ViewPager) view.findViewById(R.id.mainFragmentViewPager);
//
MainPageSettings mainPageSettings = mAppContext
.getParsedApplicationSettings().getMainPageSettings();
HomeFragmentViewPagerAdapter adapter = new HomeFragmentViewPagerAdapter(
mAppContext, mainPageSettings.getMainPreviewPictures());
mViewPager.setAdapter(adapter);
CirclePageIndicator circleIndicator = (CirclePageIndicator) view
.findViewById(R.id.mainFragmentViewPagerBullets);
circleIndicator.setRadius(MainActivity.dipsToPixels(mAppContext, 8));
circleIndicator.setViewPager(mViewPager);
ImageView rightButton = (ImageView) view
.findViewById(R.id.mainFragmentViewPagerRightButton);
rightButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v)
{
if (mViewPager.getAdapter() != null
&& mViewPager.getAdapter().getCount() > mViewPager
.getCurrentItem())
{
mViewPager.setCurrentItem(mViewPager.getCurrentItem() + 1);
}
}
});
ImageView leftButton = (ImageView) view
.findViewById(R.id.mainFragmentViewPagerLeftButton);
leftButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mViewPager.getAdapter() != null
&& mViewPager.getCurrentItem() > 0) {
mViewPager.setCurrentItem(mViewPager.getCurrentItem() - 1);
}
}
});
if (mViewPager.getAdapter() != null
&& mViewPager.getAdapter().getCount() < 2) {
leftButton.setVisibility(View.GONE);
rightButton.setVisibility(View.GONE);
} else {
leftButton.setVisibility(View.VISIBLE);
rightButton.setVisibility(View.VISIBLE);
}
mReservationButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerFirstRowReservationButton);
mReservationButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onReservationButtonClicked();
}
});
mRoomsButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerFirstRowRoomsButton);
mRoomsButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onRoomsButtonClicked();
}
});
mRatesButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerSecondRowRatesButton);
mRatesButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onRatesButtonClicked();
}
});
mFacilitiesButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerSecondRowFacilitiesButton);
mFacilitiesButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onFacilitiesButtonClicked();
}
});
mGalleryButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerThirdRowGalleryButton);
mGalleryButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onGalleryButtonClicked();
}
});
mLocationsButton = (RelativeLayout) view
.findViewById(R.id.mainFragmentButtonsContainerThirdRowLocationsButton);
mLocationsButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mActionListener.onLocationsButtonClicked();
}
});
return view;
}
updated second logcat
this second updqated logcat showing error of home_fragment
that showing error on first fragment
this second updqated logcat showing error of home_fragment
that showing error on first fragment
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'com.example.admin.myapplication.models.MainPageSettings com.example.admin.myapplication.models.ParsedApplicationSettings.getMainPageSettings()' on a null object reference
at com.example.admin.myapplication.fragments.HomeFragment.onCreateView(HomeFragment.java:90)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1974)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1252)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1234)
at android.support.v4.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:2046)
at android.support.v4.app.FragmentController.dispatchActivityCreated(FragmentController.java:174)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:597)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1220)
at android.app.Activity.performStart(Activity.java:5949)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2261)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
public class App extends Application {
private static final String TAG = PubApp.class.getSimpleName();
private static App instance;
public static Context getAppContext(){
return instance.getApplicationContext();
}
@Override
public void onCreate() {
instance = this;
super.onCreate();
}
}
<application
android:name=".App"
...
</application>
private ApplicationContext mAppContext = new ApplicationContext();
private Context mContext;
public static HomeFragment newInstance(Context context,
ActionListener actionListener) {
...
mContext = context;
...
}
HomeFragment.newInstance(getApplicationContext(), listener);