Android recyclerView的运行时异常
我试图在recyclerView中显示数据,但我的应用程序崩溃了 公共类搜索\书籍\管理员扩展AppCompative活动{Android recyclerView的运行时异常,android,sqlite,android-recyclerview,Android,Sqlite,Android Recyclerview,我试图在recyclerView中显示数据,但我的应用程序崩溃了 公共类搜索\书籍\管理员扩展AppCompative活动{ ArrayList<Model_class> modelClassArrayList; myAdapert myadapter; RecyclerView recyclerView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedIn
ArrayList<Model_class> modelClassArrayList;
myAdapert myadapter;
RecyclerView recyclerView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
recyclerView = (RecyclerView) findViewById(R.id.rv);
setContentView(R.layout.activity_search_book_admin);
modelClassArrayList = new ArrayList<>();
AddItems();
myadapter = new myAdapert(modelClassArrayList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(myadapter);
}
private void AddItems()
{
try {
for(int i=0;i<20;i++)
{
modelClassArrayList.add(new Model_class(R.drawable.ic_action_name,
"name: "+i,
"email"+i));
}
}
catch (Exception e)
{
Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
}
@Override
public void onBackPressed() {
finish();
}
ArrayList模型类ArrayList;
myAdapert-myadapter;
回收视图回收视图;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
recyclerView=(recyclerView)findViewById(R.id.rv);
setContentView(R.layout.activity\u search\u book\u admin);
modelClassArrayList=新建ArrayList();
AddItems();
myadapter=新的myAdapert(modelClassArrayList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(新的LinearLayoutManager(本));
recyclerView.setAdapter(myadapter);
}
私有void附加项()
{
试一试{
对于(inti=0;i将此代码粘贴到onCreate方法中
setContentView(R.layout.activity_search_book_admin);
recyclerView = (RecyclerView) findViewById(R.id.rv);
modelClassArrayList = new ArrayList<>();
AddItems();
myadapter = new myAdapert(modelClassArrayList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(myadapter);
setContentView(R.layout.activity\u search\u book\u admin);
recyclerView=(recyclerView)findViewById(R.id.rv);
modelClassArrayList=新建ArrayList();
AddItems();
myadapter=新的myAdapert(modelClassArrayList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(新的LinearLayoutManager(本));
recyclerView.setAdapter(myadapter);
将此代码粘贴到onCreate方法中
setContentView(R.layout.activity_search_book_admin);
recyclerView = (RecyclerView) findViewById(R.id.rv);
modelClassArrayList = new ArrayList<>();
AddItems();
myadapter = new myAdapert(modelClassArrayList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(myadapter);
setContentView(R.layout.activity\u search\u book\u admin);
recyclerView=(recyclerView)findViewById(R.id.rv);
modelClassArrayList=新建ArrayList();
AddItems();
myadapter=新的myAdapert(modelClassArrayList);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(新的LinearLayoutManager(本));
recyclerView.setAdapter(myadapter);
你确定你正确初始化了recyclerview吗?你的布局是什么?setContentView应该在findViewById之前调用。你确定你正确初始化了recyclerview吗?你的布局是什么?setContentView应该在findViewById之前调用。你在设置布局之前初始化了recycler。这就是它的原因向您提供空指针异常。请向上投票答案。这样其他人就可以知道。它已被解决。请按答案旁边的向上箭头按钮。在设置布局之前,您初始化了回收器。这就是它向您提供空指针异常的原因。请向上投票答案。这样其他人就可以知道。它已被解决按答案旁边的向上箭头状按钮