我正在关注slidenerd Material design tutorial (Android RecyclerView 示例第 1、2、3、4 部分)&我正在使用真实设备来测试我的 Android 应用程序。我已成功构建抽屉导航&当我尝试通过添加适配器(ThalakazAdapter.java)将 RecylerView 添加到其中时，不幸的是应用程序停下来。
这是我的 NavigationDrawerFragment.java
package com.thaalakaz.nadeesha.materialdesignapp1;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
//import android.app.Fragment;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.app.Fragment;
import java.util.ArrayList;
import java.util.List;
/**
* A simple {@link Fragment} subclass.
*/
public class NavigationDrawerFragment extends Fragment {
private RecyclerView recyclerView;
public static final String PREF_FILE_NAME = "testpref";
public static final String KAY_USER_LEARNED_DRAWER ="user_learned_drawer";
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private ThalakazAdapter adapter;
private boolean mUserLearnedDrawer;
private boolean mFromSavedInstanceState;
private View containerView;
public NavigationDrawerFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mUserLearnedDrawer=Boolean.valueOf(readFromPreferences(getActivity(),KAY_USER_LEARNED_DRAWER,"false"));
if (savedInstanceState != null){
mFromSavedInstanceState = true;
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View layout = inflater.inflate(R.layout.fragment_navigation_drawer, container, false);
recyclerView = (RecyclerView) layout.findViewById(R.id.drawer_layout);
adapter = new ThalakazAdapter(getActivity(),getData());
recyclerView.setAdapter(adapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
return layout;
}
public static List<Information> getData(){
List<Information> data = new ArrayList<>();
int[] icons ={R.drawable.ic_m,R.drawable.ic_m1,R.drawable.ic_m2,R.drawable.ic_m3};
String[] titles = {"Nadeesha","Thilakarathne","Semini","Roshani"};
for (int i=0;i<titles.length && i<icons.length;i++){
Information current = new Information();
current.iconId = icons[i];
current.titlel = titles[i];
data.add(current);
}
return data;
}
public void setUp(int fragmentId, DrawerLayout drawerLayout, final Toolbar toolbar) {
containerView = getActivity().findViewById(fragmentId);
mDrawerLayout = drawerLayout;
mDrawerToggle = new ActionBarDrawerToggle(getActivity(),drawerLayout,toolbar,R.string.drawer_open,R.string.drawer_close){
@Override
public void onDrawerOpened(View drawerView) {
super.onDrawerOpened(drawerView);
if(!mUserLearnedDrawer){
mUserLearnedDrawer = true;
saveToPreferences(getActivity(),KAY_USER_LEARNED_DRAWER,mUserLearnedDrawer+"");
}
getActivity().invalidateOptionsMenu();
}
@Override
public void onDrawerClosed(View drawerView) {
super.onDrawerClosed(drawerView);
getActivity().invalidateOptionsMenu();
}
@Override
public void onDrawerSlide(View drawerView, float slideOffset) {
if (slideOffset<0.6){
toolbar.setAlpha(1-slideOffset);
}
}
};
if (!mUserLearnedDrawer && mFromSavedInstanceState){
mDrawerLayout.openDrawer(containerView);
}
mDrawerLayout.setDrawerListener(mDrawerToggle);
mDrawerLayout.post(new Runnable() {
@Override
public void run() {
mDrawerToggle.syncState();
}
});
}
public static void saveToPreferences(Context context,String prferenceName,String preferenceValue){
SharedPreferences sharedPreferences = context.getSharedPreferences(PREF_FILE_NAME,Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString(prferenceName,preferenceValue);
editor.apply();
}
public static String readFromPreferences(Context context,String prferenceName,String defaultValue){
SharedPreferences sharedPreferences = context.getSharedPreferences(PREF_FILE_NAME,Context.MODE_PRIVATE);
return sharedPreferences.getString(prferenceName,defaultValue);
}
}
这是我的适配器(ThalakazAdapter.java)
package com.thaalakaz.nadeesha.materialdesignapp1;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import java.util.Collections;
import java.util.List;
/**
* Created by hp on 7/22/2015.
*/
public class ThalakazAdapter extends RecyclerView.Adapter <ThalakazAdapter.myViewHolder>{
private LayoutInflater inflater;
List<Information> data = Collections.emptyList();
public ThalakazAdapter(Context context, List<Information> data){
inflater=LayoutInflater.from(context);
this.data = data;
}
@Override
public myViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view=inflater.inflate(R.layout.custom_row, parent, false);
myViewHolder holder = new myViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(myViewHolder holder, int position) {
Information current = data.get(position);
holder.title.setText(current.titlel);
holder.icon.setImageResource(current.iconId);
}
@Override
public int getItemCount() {
return 0;
}
class myViewHolder extends RecyclerView.ViewHolder{
ImageView icon;
TextView title;
public myViewHolder(View itemView) {
super(itemView);
title = (TextView) itemView.findViewById(R.id.listText);
icon = (ImageView) itemView.findViewById(R.id.listIcon);
}
}
}
我的信息.java类
package com.thaalakaz.nadeesha.materialdesignapp1;
/**
* Created by hp on 7/22/2015.
*/
public class Information {
int iconId;
String titlel;
}
您可以从here查看我的整个项目
日志猫
07-21 22:32:07.101 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 D/dalvikvm﹕ Late-enabling CheckJNI
07-21 22:32:07.111 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 I/SystemProperties﹕ get key=ro.kernel.android.tracing
07-21 22:32:07.281 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 I/dalvikvm﹕ Could not find method android.view.ViewGroup.onRtlPropertiesChanged, referenced from method android.support.v7.widget.Toolbar.onRtlPropertiesChanged
07-21 22:32:07.281 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 W/dalvikvm﹕ VFY: unable to resolve virtual method 14685: Landroid/view/ViewGroup;.onRtlPropertiesChanged (I)V
07-21 22:32:07.281 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 D/dalvikvm﹕ VFY: replacing opcode 0x6f at 0x0007
07-21 22:32:07.301 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.internal.widget.TintTypedArray.getChangingConfigurations
07-21 22:32:07.301 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 W/dalvikvm﹕ VFY: unable to resolve virtual method 414: Landroid/content/res/TypedArray;.getChangingConfigurations ()I
07-21 22:32:07.301 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
07-21 22:32:07.311 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 I/dalvikvm﹕ Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.internal.widget.TintTypedArray.getType
07-21 22:32:07.311 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 W/dalvikvm﹕ VFY: unable to resolve virtual method 436: Landroid/content/res/TypedArray;.getType (I)I
07-21 22:32:07.311 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0002
07-21 22:32:07.381 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 D/AndroidRuntime﹕ Shutting down VM
07-21 22:32:07.381 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x41027208)
07-21 22:32:07.391 7099-7099/com.thaalakaz.nadeesha.materialdesignapp1 E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.thaalakaz.nadeesha.materialdesignapp1/com.thaalakaz.nadeesha.materialdesignapp1.MainActivity}: android.view.InflateException: Binary XML file line #24: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
at android.app.ActivityThread.access$600(ActivityThread.java:123)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4424)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:787)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:554)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.view.InflateException: Binary XML file line #24: Error inflating class fragment
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:697)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:742)
at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:249)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:106)
at com.thaalakaz.nadeesha.materialdesignapp1.MainActivity.onCreate(MainActivity.java:20)
at android.app.Activity.performCreate(Activity.java:4465)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
at android.app.ActivityThread.access$600(ActivityThread.java:123)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4424)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:787)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:554)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.thaalakaz.nadeesha.materialdesignapp1.NavigationDrawerFragment.onCreateView(NavigationDrawerFragment.java:63)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1789)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:924)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1116)
at android.support.v4.app.FragmentManagerImpl.addFragment(FragmentManager.java:1218)
at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:2170)
at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:300)
at android.support.v7.app.AppCompatDelegateImplV7.callActivityOnCreateView(AppCompatDelegateImplV7.java:838)
at android.support.v7.app.AppCompatDelegateImplV11.callActivityOnCreateView(AppCompatDelegateImplV11.java:34)
at android.support.v7.app.AppCompatDelegateImplV7.onCreateView(AppCompatDelegateImplV7.java:826)
at android.support.v4.view.LayoutInflaterCompatHC$FactoryWrapperHC.onCreateView(LayoutInflaterCompatHC.java:44)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:668)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:742)
at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:249)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:106)
at com.thaalakaz.nadeesha.materialdesignapp1.MainActivity.onCreate(MainActivity.java:20)
at android.app.Activity.performCreate(Activity.java:4465)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
at android.app.ActivityThread.access$600(ActivityThread.java:123)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4424)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:787)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:554)
at dalvik.system.NativeStart.main(Native Method)
fragment_navigation_drawer.xml
<RelativeLayout 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"
android:background="#DADADA"
tools:context="com.thaalakaz.nadeesha.materialdesignapp1.NavigationDrawerFragment">
<LinearLayout
android:id="@+id/containerDrawerImage"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#FF6F00">
<ImageView
android:layout_width="280dp"
android:layout_height="140dp"
android:src = "@drawable/dog"
android:layout_margin="16dp"/>
</LinearLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/drawerList"
android:layout_height="match_parent"
android:layout_width="wrap_content">
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
最佳答案
在你的onCreateView中你正在寻找错误的id。改变
recyclerView = (RecyclerView) layout.findViewById(R.id.drawer_layout);
与
recyclerView = (RecyclerView) layout.findViewById(R.id.drawerList);
我还注意到，在您的 Adapter 的构造函数中，您将 this.data 分配给自身。改变
this.data = this.data;
到
this.data = data
和getItemCount不应返回0，而是数据的大小(如果不为空)
关于java - 不幸的是，当尝试实现 RecyclerView 时，应用程序在 Android 中停止了，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/31545038/