無法使用onItemClickListener獲取數據

我想要onItem點擊列表視圖並進入DetailsPage以顯示詳細信息，但它讓我爲空。 ListView中的項目是圖片網址，名稱和地址。 DetailsPage中的項目是圖片網址，名稱，地址，聯繫人和類別。無法使用onItemClickListener獲取數據

Image of the view on my phone when get null

這是我ListViewPage

public class ImageListActivity extends AppCompatActivity { 

private DatabaseReference mDatabaseRef; 
private List<ImageUpload> imgList; 
private ListView lv; 
private ImageListAdapter adapter; 
private ProgressDialog progressDialog; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_image_list); 
    imgList = new ArrayList<>(); 
    lv = (ListView) findViewById(R.id.listViewImage); 
    progressDialog = new ProgressDialog(this); 
    progressDialog.setMessage("Please wait loading list image..."); 
    progressDialog.show(); 

    mDatabaseRef = FirebaseDatabase.getInstance().getReference(WorkshopsInfoActivity.FB_DATABASE_PATH); 

    mDatabaseRef.addValueEventListener(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      progressDialog.dismiss(); 
      for (DataSnapshot snapshot : dataSnapshot.getChildren()) { 
       ImageUpload img = snapshot.getValue(ImageUpload.class); 
       imgList.add(img); 
      } 
      adapter = new ImageListAdapter(ImageListActivity.this, R.layout.image_item, imgList); 
      lv.setAdapter(adapter); 
     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

      progressDialog.dismiss(); 
     } 
    }); 
    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) { 
      Intent intent = new Intent(getApplicationContext(), DetailsOfWorkshops.class); 
      startActivity(intent); 
     } 
    }); 
}}

這是我DetailsPage

public class DetailsOfWorkshops extends AppCompatActivity { 

DatabaseReference mDatabaseRef; 
List<ImageUpload> listImage; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_details_of_workshops); 
    mDatabaseRef = FirebaseDatabase.getInstance().getReference(WorkshopsInfoActivity.FB_DATABASE_PATH); 
    mDatabaseRef.addValueEventListener(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      ImageUpload img = dataSnapshot.getValue(ImageUpload.class); 

      String name = img.getName(); 
      String address = img.getAddress(); 
      String contact = img.getContact(); 
      String category = img.getCategory(); 


      final TextView textViewDetails = (TextView) findViewById(R.id.tvName); 
      String string = "Name: " + name + "\nAddress: " + address + "\nContact: " + contact + "\nCategory: " + category + "\n\n"; 
      textViewDetails.setText(string); 
     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

     } 
    }); 
}}

來源

2017-04-22 Brush Lee

你送什麼給細節等級：

Intent intent = new Intent(getApplicationContext(), DetailsOfWorkshops.class); 
     startActivity(intent);

嘗試使用此：

YourClass item = (YourClass) adapterView.getAdapter().getItem(position); 
Intent intent = new Intent(getApplicationContext().this, DetailsOfWorkshops.class); 
Bundle bundle = new Bundle(); 
bundle.putString("valueName", value); 
intent.putExtra("MyPackage", bundle); 
startActivity(intent);

來源

2017-04-22 02:53:24 julanove

對不起，我仍然無法得到它。我的DetailsPage中的代碼有問題嗎？ –

問題先生是您不會將任何內容從ImageListActivity發送到DetailsPage活動，以指示要顯示哪個項目。請像上面的Rajesh傢伙一樣做，看看不同。 – julanove

我們需要從ActivityOne發送一些數據通過意圖ActivityTwo然後訪問ActivityTwo數據並將其設置爲所需的TextView。

請在ActivityOne中查看以下代碼。

public class ImageListActivity extends AppCompatActivity { 

private DatabaseReference mDatabaseRef; 
public List<ImageUpload> imgList; 
private ListView lv; 
private ImageListAdapter adapter; 
private ProgressDialog progressDialog; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_image_list); 
    imgList = new ArrayList<>(); 
    lv = (ListView) findViewById(R.id.listViewImage); 
    progressDialog = new ProgressDialog(this); 
    progressDialog.setMessage("Please wait loading list image..."); 
    progressDialog.show(); 

    mDatabaseRef = FirebaseDatabase.getInstance().getReference(WorkshopsInfoActivity.FB_DATABASE_PATH); 

    mDatabaseRef.addValueEventListener(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      progressDialog.dismiss(); 
      for (DataSnapshot snapshot : dataSnapshot.getChildren()) { 
       ImageUpload img = snapshot.getValue(ImageUpload.class); 
       imgList.add(img); 
      } 
      adapter = new ImageListAdapter(ImageListActivity.this, R.layout.image_item, imgList); 
      lv.setAdapter(adapter); 
     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

      progressDialog.dismiss(); 
     } 
    }); 
    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) { 

      ImageUpload itemData = imgList.get(i); 
      Intent intent = new Intent(getApplicationContext(), DetailsOfWorkshops.class); 
      intent.putExtra("name", itemData.getName()); 
      intent.putExtra("address", itemData.getAddress()); 
      intent.putExtra("contact", itemData.getContact());  
      intent.putExtra("category", itemData.getCatogory());  
      startActivity(intent); 
     } 
    }); 
}}

檢查出一些變化ActivityTwo

public class DetailsOfWorkshops extends AppCompatActivity { 

DatabaseReference mDatabaseRef; 
List<ImageUpload> listImage; 

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

    String name = getIntent().getStringExtra("name"); 
    String address = getIntent().getStringExtra("address"); 
    String contact = getIntent().getStringExtra("contact"); 
    String category = getIntent().getStringExtra("category"); 


    TextView textViewDetails = (TextView) findViewById(R.id.tvName); 
    String string = "Name: " + name + "\nAddress: " + address + "\nContact: " + contact + "\nCategory: " + category + "\n\n"; 
    textViewDetails.setText(string); 

    mDatabaseRef = FirebaseDatabase.getInstance().getReference(WorkshopsInfoActivity.FB_DATABASE_PATH); 
    mDatabaseRef.addValueEventListener(new ValueEventListener() { 
     @Override 
     public void onDataChange(DataSnapshot dataSnapshot) { 
      ImageUpload img = dataSnapshot.getValue(ImageUpload.class); 
     } 

     @Override 
     public void onCancelled(DatabaseError databaseError) { 

     } 
    }); 
}}

希望這會有所幫助。

@Rajesh

來源

2017-04-22 04:39:14

非常感謝。這是工作 –

嘗試onItemSelected聽衆，而不是onItemClick監聽器這會給你它可以幫助您獲得特定對象想要其數據然後你就可以適當值發送額外的位置

 ImageUpload itemData = imgList.get(pos); 
     Intent intent = new Intent(getApplicationContext(), 
     DetailsOfWorkshops.class); 
     intent.putExtra("name", itemData.getName()); 
     intent.putExtra("address", itemData.getAddress()); 
     intent.putExtra("contact", itemData.getContact());  
     intent.putExtra("category", itemData.getCatogory());  
     startActivity(intent);

OnClick監聽器適用於整個視圖而不是特定元素byt OnSelected給出您在列表中選擇的項目的位置查看

來源

2017-04-22 12:35:23

無法使用onItemClickListener獲取數據

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