フラグメントからのクリックが実行されたときにアクティビティを開始できません

Question

すべて私がクリックしたいと思っているもの画像 open-私は知っているすべてを試して、Googleのアドバイスから多くを試してみました。しかし、何もうまくいきません。

Main_Activity.java

package com.example.wolfknight.tabbed; 

import android.support.design.widget.TabLayout; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 

import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentManager; 
import android.support.v4.app.FragmentPagerAdapter; 
import android.support.v4.view.ViewPager; 
import android.os.Bundle; 
import android.view.LayoutInflater; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.view.ViewGroup; 


public class MainActivity extends AppCompatActivity { 

    private SectionsPagerAdapter mSectionsPagerAdapter; 

    private ViewPager mViewPager; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
     setSupportActionBar(toolbar); 
     mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager()); 
     mViewPager = (ViewPager) findViewById(R.id.container); 
     mViewPager.setAdapter(mSectionsPagerAdapter); 
     TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs); 
     tabLayout.setupWithViewPager(mViewPager); 
    } 
    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     getMenuInflater().inflate(R.menu.menu_main, menu); 
     return true; 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     int id = item.getItemId(); 
     if (id == R.id.action_settings) { 
      return true; 
     } 

     return super.onOptionsItemSelected(item); 
    } 
    public static class PlaceholderFragment extends Fragment { 
     private static final String ARG_SECTION_NUMBER = "section_number"; 

     public PlaceholderFragment() { 
     } 
     public static PlaceholderFragment newInstance(int sectionNumber) { 
      PlaceholderFragment fragment = new PlaceholderFragment(); 
      Bundle args = new Bundle(); 
      args.putInt(ARG_SECTION_NUMBER, sectionNumber); 
      fragment.setArguments(args); 
      return fragment; 
     } 

     @Override 
     public View onCreateView(LayoutInflater inflater, ViewGroup container, 
           Bundle savedInstanceState) { 
      if (getArguments().getInt(ARG_SECTION_NUMBER) == 1) { 
       View rootView = inflater.inflate(R.layout.fragment_practice, container, false); 
       return rootView; 
      } else if (getArguments().getInt(ARG_SECTION_NUMBER) == 2) { 
       View rootView = inflater.inflate(R.layout.fragment_study, container, false); 
       return rootView; 
      } 
      else 
      { 
       View rootView = inflater.inflate(R.layout.fragment_main, container, false); 
       return rootView; 

      } 
     } 

    } 
    public class SectionsPagerAdapter extends FragmentPagerAdapter { 

     public SectionsPagerAdapter(FragmentManager fm) { 
      super(fm); 
     } 

     @Override 
     public Fragment getItem(int position) { 
      return PlaceholderFragment.newInstance(position + 1); 
     } 
     @Override 
     public int getCount() { 
      return 2; 
     } 

     @Override 
     public CharSequence getPageTitle(int position) { 
      switch (position) { 
       case 0: 
        return "class"; 
       case 1: 
        return "Practice"; 
      } 
      return null; 
     } 
    } 
} 

そして....フラグメントpractice.java

package layout; 

import android.content.Context; 
import android.content.Intent; 
import android.net.Uri; 
import android.os.Bundle; 
import android.support.v4.app.Fragment; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.Button; 
import android.widget.ImageView; 

import com.example.wolfknight.tabbed.R; 
import com.example.wolfknight.tabbed.Lego; 
public class practice extends Fragment { 

    private static final String ARG_PARAM1 = "param1"; 
    private static final String ARG_PARAM2 = "param2"; 

    private String mParam1; 
    private String mParam2; 

    private OnFragmentInteractionListener mListener; 

    public practice() {} 
    public static practice newInstance(String param1, String param2) { 
     practice fragment = new practice(); 
     Bundle args = new Bundle(); 
     args.putString(ARG_PARAM1, param1); 
     args.putString(ARG_PARAM2, param2); 
     fragment.setArguments(args); 
     return fragment; 
    } 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     if (getArguments() != null) { 
      mParam1 = getArguments().getString(ARG_PARAM1); 
      mParam2 = getArguments().getString(ARG_PARAM2); 
     } 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
          Bundle savedInstanceState) { 
     View view = inflater.inflate(R.layout.fragment_practice, container, false); 
     ImageView mButton = (ImageView) view.findViewById(R.id.image); 

     mButton.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View v) { 
       Intent intent = new Intent(getActivity(), Lego.class); 
       startActivity(intent); 

      } 
     }); 
     return view; 
     } 
    public void onButtonPressed(Uri uri) { 
     if (mListener != null) { 
      mListener.onFragmentInteraction(uri); 
     } 
    } 

    @Override 
    public void onAttach(Context context) { 
     super.onAttach(context); 
     if (context instanceof OnFragmentInteractionListener) { 
      mListener = (OnFragmentInteractionListener) context; 
     } else { 
      throw new RuntimeException(context.toString() 
        + " must implement OnFragmentInteractionListener"); 
     } 
    } 

    @Override 
    public void onDetach() { 
     super.onDetach(); 
     mListener = null; 
    } 
    public interface OnFragmentInteractionListener { 
     void onFragmentInteraction(Uri uri); 
    } 
} 

XML部分が正常に動作します>> ..アプリは、同様に動作しますが、何もクリックに応答しません。

Answer 1

代わりにボタンonClickListenerをonViewCreatedに設定してみてください。

Answer 2

次のようなonActivityCreatedであなたにonClickListenerを設定する必要があります。

@Override 
public void onActivityCreated(Bundle savedInstanceState) { 
    super.onActivityCreated(savedInstanceState); 
    ImageView mButton = (ImageView) view.findViewById(R.id.image); 

     mButton.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View v) { 
       Intent intent = new Intent(getActivity(), Lego.class); 
       startActivity(intent); 

      } 
     }); 
}