如何在Android GridView中获取唯一的视图ID或标签

Question

我使用CustomGridView拥有ImageViews 。 如何在android GridView获取视图的唯一标识符。 知道android回收视图，所以如果我这样做view.setTag(); 我可能将多个标签设置为一个视图。

我想我必须使用view.setTag(); 命令，但是我应该放在哪里？

这是我的代码：

import java.io.File;
import java.util.ArrayList;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.CompoundButton;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ToggleButton;


public class CustomGridViewAdapter extends BaseAdapter {

    private LayoutInflater inflater = null;
    private final String TAG = "CustomGridViewAdapter";
    public Context mContext;
    public int layoutResourceId;
    public Bitmap icon;
    private ArrayList<String> itemList = new ArrayList<String>();
    private ArrayList<Bitmap> bitmapList = new ArrayList<Bitmap>();
    public ArrayList<CustomGridViewAdapter.GridHolder> mViews = new ArrayList<CustomGridViewAdapter.GridHolder>();


    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public CustomGridViewAdapter(Context context) {
        // TODO Auto-generated constructor stub
        Log.i(TAG, "costruttore");
        this.mContext = context;
        cont = 0;
    }

    public void add(String path) {
        Log.i(TAG, "adding path: " + path);
        itemList.add(path);
    }

    public void addBitmap(Bitmap bm) {
        Log.i(TAG, "adding bitmap");
        bitmapList.add(bm);
    }

    @Override
    public int getCount() {
        return itemList.size();
        //return bitmapList.size();
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        Log.w(TAG, "im in getItem");
        return itemList.get(position);
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        Log.i(TAG, "getItemId");
        return position;
    }


    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        Log.i(TAG, "im in getView");

        View view = convertView;
        GridHolder holder = null;

        if (view == null) {

            inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            view = inflater.inflate(R.layout.grid_elements, null);

            holder = new GridHolder();
            holder.btnAddPhoto = (Button) view.findViewById(R.id.btnAddPhoto);
            holder.ivAddedPhoto = (ImageView) view.findViewById(R.id.ivAddedPhoto);
            holder.ivFeaturedImage = (ImageView) view.findViewById(R.id.ivFeaturedImage);
            holder.ivDeleteImageButton = (ImageView) view.findViewById(R.id.ivDeleteImageButton);
            holder.ivFirstPhoto = (ToggleButton) view.findViewById(R.id.ivFirstPhoto);
            holder.ivFeaturedImage.setVisibility(View.GONE);

            view.setTag(holder);

            //i was trying to add a tag to each single view but it seems that when it recycles it associates new tags to the view.
            //i would like to have 1 tag per view
            //mViews.add(holder);

        } else {
            holder = (GridHolder) view.getTag();
        }

        Bitmap bm = decodeSampledBitmapFromUri(itemList.get(position), 95, 95);
        holder.ivAddedPhoto.setImageBitmap(bm);

        //mViews.add((GridHolder) view.getTag(position));
        holder.ivDeleteImageButton.setVisibility(View.VISIBLE);
        holder.ivDeleteImageButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Log.i(TAG, "PositionD: " + Integer.toString(position));
                File file= new File(itemList.get(position));
                if(file.exists()) {
                     file.delete();
                }
                itemList.remove(position);
                notifyDataSetChanged();
            }
        });



        holder.ivFirstPhoto.setTag(holder);
        holder.ivFirstPhoto.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

                Log.i(TAG, "Position First Photo: " + Integer.toString(position));
                Log.i(TAG, "Tag is: " + buttonView.getTag().toString());
                Log.i(TAG, "mViews size: " + Integer.toString(mViews.size()));
                Log.i(TAG, "getCount size: " + Integer.toString(getCount()));
                Log.i(TAG, "id's: " + Integer.toString(getCount()));


                GridHolder holderView;

                //set all the ivFeaturedImage to invisible
                for (int i=0; i < mViews.size(); i++){
                    Log.i(TAG, "mViews elm: " + mViews.get(i).toString());
                    holderView = mViews.get(i);
                    holderView.ivFeaturedImage.setVisibility(View.GONE);
                }

                holderView = (GridHolder) buttonView.getTag();

                if (isChecked) {
                    buttonView.setBackgroundResource(R.drawable.first_photo_on);
                    holderView.ivFeaturedImage.setVisibility(View.VISIBLE);
                } else {
                    buttonView.setBackgroundResource(R.drawable.first_photo_off);
                    holderView.ivFeaturedImage.setVisibility(View.GONE);
                }

                //notifyDataSetChanged();
                //view.setVisibility(View.VISIBLE);
            }
        });

        return view;

    }

    static class GridHolder {
        ImageView ivAddedPhoto;
        ImageView ivFeaturedImage;
        ImageView ivDeleteImageButton;
        ToggleButton ivFirstPhoto;
        Button btnAddPhoto;
        int id;
    }


    public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {

        Bitmap bm = null;
        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(path, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bm = BitmapFactory.decodeFile(path, options);

        return bm;
    }

    public int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {

        // Raw height and width of image
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {
            if (width > height) {
                inSampleSize = Math.round((float) height / (float) reqHeight);
            } else {
                inSampleSize = Math.round((float) width / (float) reqWidth);
            }
        }
        return inSampleSize;
    }
}

Answer 1

这样做在您的适配器中创建自定义支架

private static class ViewHolder {
        public long id;
        public ImageView coverView;
}

然后创建一个新视图并在适配器中对其进行充气

View view = mInflater.inflate(layout, null);
ViewHolder holder = new ViewHolder();
holder.coverView = your image resource ;
holder.id = your id ;
view.setTag(holder);

然后只需return view

希望这有助于让我知道，如果您不了解，我也可以发布适当的书面代码..