How to assing an Image to Imageview based on a query results?

问题

Good afternoon everyone,

I have a quick question. I have a query result that I store in a list/array and I am trying to display the appropriate image in the imageview. The query provides a name of the image that is stored in the resource folder(res/drawable). I am getting error syntax. I am not sure how to solve this issue. I have a database that stores the name of the image in a field (database) called spic.

I have tried this code:

how to work with images and database in android?

but it doesnt work in this class. I am not sure is it because this class is "extends ArrayAdapter {" instead of "extends Activity {"

here is my code:

zCustomUsersAdapter class:

  package com.example.yao;

  import java.util.ArrayList;
  import java.util.List;

  import android.content.Context;
  import android.graphics.drawable.Drawable;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.ArrayAdapter;
  import android.widget.ImageView;
  import android.widget.TextView;

  public class zCustomUsersAdapter extends ArrayAdapter<YAOYVD> {

      public zCustomUsersAdapter(Context context, List<YAOYVD> users) {
          super(context, 0, users);

       }

       @Override
       public View getView(int position, View convertView, ViewGroup parent) {
          // Get the data item for this position
         // User user = getItem(position);
           YAOYVD user = getItem(position); 
          // Check if an existing view is being reused, otherwise inflate the view
          if (convertView == null) {
             convertView = LayoutInflater.from(getContext()).inflate(R.layout.zitem_user, parent, false);
          }
          // Lookup view for data population
          TextView tvName = (TextView) convertView.findViewById(R.id.tvName);
          TextView tvHome = (TextView) convertView.findViewById(R.id.tvHometown);

          ImageView tvImage = (ImageView) convertView.findViewById(R.id.ivUserIcon);
          // Populate the data into the template view using the data object
          tvName.setText(String.valueOf(user.getID_YAO()));
                //.name);
          tvHome.setText(String.valueOf(user.getNAME_YAO()));
          //.hometown);

        //  tvImage.setBackgroundResource( getResourceID (String.valueOf(user.getSPIC_YAO()), "drawable",getApplicationContext() ));
          // Return the completed view to render on screen


          tvImage.setBackgroundResource(user.getSPIC_YAO());  //getSpic_YAO this is string in the YAO class. getSpic_YAO retrive the name of the image in the drawable folder.

         return convertView;
     }

 }

zCustomListActivity

 package com.example.yao;

 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;

 import android.app.Activity;
 import android.content.Context;
 import android.database.SQLException;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.ImageView;
 import android.widget.ListView;

 public class zCustomListActivity extends Activity {

     private YAOGetDataSource2 datasource;


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

        //calling the method to create the database from asset folder
         copydbfromassest();

        // datasource = new YAODeckListDataSource(this);
        datasource = new YAOGetDataSource2(this);
         datasource.open();


         populateUsersList();

    }



     private void populateUsersList() {
         // Construct the data source
         //List<YAOYVD> values = datasource.SQLYVDTABLESEARCH();  
         List<YAOYVD> arrayOfUsers = datasource.SQLYVDTABLESEARCH(); 
                //.getUsers();
         // Create the adapter to convert the array to views
         zCustomUsersAdapter adapter = new zCustomUsersAdapter(this, arrayOfUsers);
         // Attach the adapter to a ListView
         ListView listView = (ListView) findViewById(R.id.lvUsers);
         listView.setAdapter(adapter);
    }

     //@Override
         public void onClick(View view) {
             // TODO Auto-generated method stub

        }


         //database open and close
         @Override
         protected void onResume() {
         datasource.open();
         super.onResume();
         }

         @Override
         protected void onPause() {
         datasource.close();
         super.onPause();
         }

         @Override
         protected void onDestroy(){
           datasource.close();
           super.onDestroy();

         }


     /****
     * new things to considered
     */
         ///copy the database from assest folder

         private void copydbfromassest() {
             // TODO Auto-generated method stub
             YAOMySQLiteHelper myhelper = new YAOMySQLiteHelper (this);

            try{
                //create datbase
                myhelper.importIfNotExist();
             }catch (IOException e){

                throw new Error("Unable to Create the Database ");

             }

            try{
                myhelper.openDataBase();
            }catch (SQLException sqle){

                throw sqle;
            }
         }

 }

回答1:

You need to retrieve the resource identifier associated with that image's name. For this, you will need to get your app's Resources, which requires a context.

Context ctx = getContext();
int resId = ctx.getResources().getIdentifier(user.getSPIC_YAO(), "drawable", ctx.getPackageName());
if(resId != 0){
    tvImage.setBackgroundResource(resId);
}

来源：https://stackoverflow.com/questions/26851592/how-to-assing-an-image-to-imageview-based-on-a-query-results