Steve Kamau Steve Kamau - 15 days ago 20
Android Question

How to open a different activity on recyclerView item onclick

i am using a

recyclerView
to show my
listitems
in the
navigation drawer
.I have implemented the
onclickListener
but i have been stuck on how to open a different
activity
when items are
clicked
. All my items do on item click as of now as per the code is to display a
toast
with the
item position
.

I would appreciate the help.

AdapterClass.java



public class AdapterClass extends RecyclerView.Adapter<AdapterClass.MyViewHolder> {
private LayoutInflater inflater;
private Context context;
List<Information>data= Collections.emptyList();
public AdapterClass(Context context,List<Information>data){
this.context=context;

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.title);
holder.icon.setImageResource(current.iconId);

}

@Override
public int getItemCount() {
return data.size();
}
class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
TextView title;
ImageView icon;

public MyViewHolder(View itemView) {
super(itemView);
title=(TextView)itemView.findViewById(R.id.listText);
icon=(ImageView)itemView.findViewById(R.id.listIcon);
itemView.setClickable(true);
itemView.setOnClickListener(this);
}

@Override
public void onClick(View v) {

Toast.makeText(context,"The Item Clicked is: "+getPosition(),Toast.LENGTH_SHORT).show();
}
};
}





Log cat error after implementing Konrad's solution

02-27 15:24:52.833: D/AndroidRuntime(1630): --------- beginning of crash
02-27 15:24:52.834: E/AndroidRuntime(1630): FATAL EXCEPTION: main
02-27 15:24:52.834: E/AndroidRuntime(1630): Process: com.snappy.stevekamau.snappy, PID: 1630
02-27 15:24:52.834: E/AndroidRuntime(1630): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.snappy.stevekamau.snappy/com.snappy.stevekamau.snappy.YourActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.support.v7.widget.Toolbar.getTitle()' on a null object reference
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.access$800(ActivityThread.java:144)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.os.Handler.dispatchMessage(Handler.java:102)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.os.Looper.loop(Looper.java:135)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.main(ActivityThread.java:5221)
02-27 15:24:52.834: E/AndroidRuntime(1630): at java.lang.reflect.Method.invoke(Native Method)
02-27 15:24:52.834: E/AndroidRuntime(1630): at java.lang.reflect.Method.invoke(Method.java:372)
02-27 15:24:52.834: E/AndroidRuntime(1630): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
02-27 15:24:52.834: E/AndroidRuntime(1630): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
02-27 15:24:52.834: E/AndroidRuntime(1630): Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.support.v7.widget.Toolbar.getTitle()' on a null object reference
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.internal.widget.ToolbarWidgetWrapper.<init>(ToolbarWidgetWrapper.java:95)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.internal.widget.ToolbarWidgetWrapper.<init>(ToolbarWidgetWrapper.java:88)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.internal.app.ToolbarActionBar.<init>(ToolbarActionBar.java:84)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.app.ActionBarActivityDelegateBase.setSupportActionBar(ActionBarActivityDelegateBase.java:175)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.app.ActionBarActivity.setSupportActionBar(ActionBarActivity.java:92)
02-27 15:24:52.834: E/AndroidRuntime(1630): at com.snappy.stevekamau.snappy.YourActivity.onCreate(YourActivity.java:18)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.Activity.performCreate(Activity.java:5933)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
02-27 15:24:52.834: E/AndroidRuntime(1630): ... 10 more
02-27 15:24:52.839: W/ActivityManager(464): Force finishing activity com.snappy.stevekamau.snappy/.YourActivity
02-27 15:24:52.841: W/ActivityManager(464): Force finishing activity com.snappy.stevekamau.snappy/.MainActivity

Answer

I think that it is easy. You can (but you don't have to because ViewHolder class is not static) create field context as is shown below:

    private final Context context;

    public MyViewHolder(View itemView) {
        super(itemView);
        context = itemView.getContext();
        ...
    }

and on your onClick method just call sth like below:

    @Override
    public void onClick(View v) {          

        final Intent intent;
        switch (getAdapterPostion()){
            case 0:
               intent =  new Intent(context, FirstActivity.class);
               break;

            case 1:
                intent =  new Intent(context, SecondActivity.class);
                break;
               ...
            default:
               intent =  new Intent(context, DefaultActivity.class);
               break;
         }
        context.startActivity(intent);
    }

or

    @Override
    public void onClick(View v) {          

        final Intent intent;
        if (getAdapterPosition() == sth){
           intent =  new Intent(context, OneActivity.class);
        } else if (getPosition() == sth2){
           intent =  new Intent(context, SecondActivity.class);
        } else {
           intent =  new Intent(context, DifferentActivity.class);
        }
        context.startActivity(intent);
    }