在我的android项目中，我有一个ListView适配器类。当我在点击按钮/项目时尝试启动此活动时，应用程序因某种原因崩溃。
我尝试使用Intent从MainActivity.java启动ActivityATwo.java，点击后，必须执行intent。
我在MainActivity.java的XML文件中添加了onClick属性
MainActivity.java
import com.test.mvsaditya.testapp.*;
import com.test.mvsaditya.testapp.activityAtwo;
.
.
.
public void onSubjects ( MenuItem item)
{
Intent toSubjects = new Intent ( MainActivity.this, activityAtwo.class);
startActivity(toSubjects);
}
ActivityATwo.java :(这是项目中的一个模块，gradle已成功构建）
package com.test.mvsaditya.testapp;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.LinearLayoutManager;
import android.os.Bundle;
import android.text.Layout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.EditText;
import java.util.*;
public class activityAtwo extends AppCompatActivity {
private final String sub_names[] = {
"Math",
"Chem",
"Physics",
"Bio",
"DBMS"
};
private final String sub_descs[] = {
"Numbers and shiz",
"Gravity and charges and shiz",
"Elements and shiz",
"Shiz",
"shizzz"
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_atwo);
RecyclerView mRecyclerView = (RecyclerView) findViewById(R.id.subjectList);
mRecyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
mRecyclerView.setLayoutManager(mLayoutManager);
ArrayList<Subjects> subjectList = prepareData();
MyAdapter adapter= new MyAdapter(getApplicationContext(),subjectList);
mRecyclerView.setAdapter(adapter);
}
private ArrayList<Subjects> prepareData(){
ArrayList<Subjects> sub = new ArrayList<>();
for(int i=0;i<sub_names.length;i++){
Subjects subObj = new Subjects(sub_names[i],sub_descs[i]);
sub.add(subObj);
}
return sub;
}
}
这是我点击按钮时所得到的：
10-05 20:57:45.550 4750-4750/com.grs.raja.collegeapp D/AndroidRuntime: Shutting down VM
10-05 20:57:45.550 4750-4750/com.grs.raja.collegeapp E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.grs.raja.collegeapp, PID: 4750
java.lang.NoSuchFieldError: No field subjectList of type I in class Lcom/test/mvsaditya/testapp/R$id; or its superclasses (declaration of 'com.test.mvsaditya.testapp.R$id' appears in /data/app/com.grs.raja.collegeapp-1/split_lib_slice_0_apk.apk)
at com.test.mvsaditya.testapp.activityAtwo.onCreate(activityAtwo.java:48)
at android.app.Activity.performCreate(Activity.java:6662)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6077)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
10-05 20:57:45.551 1647-3063/system_process W/ActivityManager: Force finishing activity com.grs.raja.collegeapp/com.test.mvsaditya.testapp.activityAtwo
10-05 20:57:45.553 1647-3063/system_process W/ActivityManager: Force finishing activity com.grs.raja.collegeapp/com.example.praharsha.myapplication.MainActivity
10-05 20:57:45.593 1647-4415/system_process I/OpenGLRenderer: Initialized EGL, version 1.4
10-05 20:57:45.593 1647-4415/system_process D/OpenGLRenderer: Swap behavior 1
10-05 20:57:45.594 1647-4415/system_process W/OpenGLRenderer: Failed to choose config with EGL_SWAP_BEHAVIOR_PRESERVED, retrying without...
10-05 20:57:45.594 1647-4415/system_process D/OpenGLRenderer: Swap behavior 0
10-05 20:57:45.652 1647-4415/system_process D/EGL_emulation: eglCreateContext: 0xa3b426c0: maj 3 min 1 rcv 4
10-05 20:57:45.777 1647-4415/system_process D/EGL_emulation: eglMakeCurrent: 0xa3b426c0: ver 3 1 (tinfo 0x97fb51e0)
10-05 20:57:45.778 1647-4415/system_process E/eglCodecCommon: glUtilsParamSize: unknow param 0x000082da
10-05 20:57:45.778 1647-4415/system_process E/eglCodecCommon: glUtilsParamSize: unknow param 0x00008cdf
10-05 20:57:45.778 1647-4415/system_process E/eglCodecCommon: glUtilsParamSize: unknow param 0x00008824
10-05 20:57:45.925 1647-4415/system_process D/EGL_emulation: eglMakeCurrent: 0xa3b426c0: ver 3 1 (tinfo 0x97fb51e0)
10-05 20:57:46.053 1647-1663/system_process W/ActivityManager: Activity pause timeout for ActivityRecord{28c80a2 u0 com.grs.raja.collegeapp/com.test.mvsaditya.testapp.activityAtwo t10 f}
10-05 20:57:48.710 1391-1415/? W/audio_hw_generic: Not supplying enough data to HAL, expected position 3370790 , only wrote 3062160
10-05 20:57:55.514 1647-1663/system_process W/ActivityManager: Launch timeout has expired, giving up wake lock!
10-05 20:58:00.006 1746-2038/com.android.systemui D/EGL_emulation: eglMakeCurrent: 0xa8205240: ver 3 1 (tinfo 0xa82032d0)
这是activity_atwo.XML布局：
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:fitsSystemWindows="true"
tools:context="com.test.mvsaditya.testapp.activityAtwo">
<android.support.v7.widget.RecyclerView
android:id="@+id/subjectList"
android:scrollbars="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</android.support.design.widget.CoordinatorLayout>
ListView适配器：
package com.test.mvsaditya.testapp;
import android.content.Context;
import android.media.Image;
import android.support.design.widget.Snackbar;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
/**
* Created by mvsaditya on 20-09-2017.
*/
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.SubHolder>
{
public ArrayList<Subjects> mDataSet; private Context context;
public static class SubHolder extends RecyclerView.ViewHolder
{
//private ImageView mItemImage;
private TextView mItemName;
ImageButton fileicon;
//private TextView mItemDescription;
//private static final String PHOTO_KEY = "PHOTO";
public SubHolder(final View v){
super(v);
//mItemDescription = (TextView)v.findViewById(R.id.item_description);
mItemName = (TextView)v.findViewById(R.id.item_name);
}
public void onClick(View v)
{
}
}
public MyAdapter(Context context, ArrayList<Subjects> myDataSet){
this.context = context;
mDataSet=myDataSet;
}
public MyAdapter.SubHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View inflatedView = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_view_item_row, parent, false);
return new SubHolder(inflatedView);
}
@Override
public void onBindViewHolder(SubHolder holder, int position) {
holder.mItemName.setText(mDataSet.get(position).Subname);
//holder.mItemDescription.setText(mDataSet.get(position).Subdescription);
}
@Override
public int getItemCount(){
return mDataSet.size();
}
}
如何解决此问题？
答案 0 :(得分：0)
Android资源和骆驼案似乎相处得不好。尝试将ActivityATwo.XML重命名为activity_atwo.xml，就像在Activity类中命名它一样。
答案 1 :(得分：0)
请尝试以下代码在我的应用中运行正常。
1. demo.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="@+id/subjectList"
android:scrollbars="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
2. recycler_view_item_row.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/item_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
3. Subjects.java
class Subjects {
String ss;
String sv;
public Subjects(String aSsa, String aSva) {
ss = aSsa;
sv = aSva;
}
public String getSv() {
return sv;
}
public void setSv(String aSva) {
sv = aSva;
}
public String getSs() {
return ss;
}
public void setSs(String aSsa) {
ss = aSsa;
}
}
4. ActivityAtwo.java
public class ActivityAtwo extends AppCompatActivity {
private final String sub_names[] = {
"Math",
"Chem",
"Physics",
"Bio",
"DBMS"
};
private final String sub_descs[] = {
"Numbers and shiz",
"Gravity and charges and shiz",
"Elements and shiz",
"Shiz",
"shizzz"
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.demo);
RecyclerView mRecyclerView = (RecyclerView) findViewById(R.id.subjectList);
mRecyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
mRecyclerView.setLayoutManager(mLayoutManager);
ArrayList<Subjects> subjectList = prepareData();
MyAdapter adapter= new MyAdapter(getApplicationContext(),subjectList);
mRecyclerView.setAdapter(adapter);
}
private ArrayList<Subjects> prepareData(){
ArrayList<Subjects> sub = new ArrayList<>();
for(int i=0;i<sub_names.length;i++){
Subjects subObj = new Subjects(sub_names[i],sub_descs[i]);
sub.add(subObj);
}
return sub;
}
}
5. MyAdapter.java
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.SubHolder> {
public ArrayList<Subjects> mDataSet;
private Context context;
public static class SubHolder extends RecyclerView.ViewHolder {
//private ImageView mItemImage;
private TextView mItemName;
ImageButton fileicon;
//private TextView mItemDescription;
//private static final String PHOTO_KEY = "PHOTO";
public SubHolder(final View v) {
super(v);
//mItemDescription = (TextView)v.findViewById(R.id.item_description);
mItemName = (TextView) v.findViewById(R.id.item_name);
}
public void onClick(View v) {
}
}
public MyAdapter(Context context, ArrayList<Subjects> myDataSet) {
this.context = context;
mDataSet = myDataSet;
}
public MyAdapter.SubHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View inflatedView = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_view_item_row, parent, false);
return new SubHolder(inflatedView);
}
@Override
public void onBindViewHolder(SubHolder holder, int position) {
holder.mItemName.setText(mDataSet.get(position).getSs());
//holder.mItemDescription.setText(mDataSet.get(position).Subdescription);
}
@Override
public int getItemCount() {
return mDataSet.size();
}
}
请尝试上面的代码，它将完美地工作。