android - 在 RecyclerView 中按下时更改图像按钮

Question

我在 RecyclerView 的 CardView 中添加了 ImageButton 并且我让它添加到收藏夹中的项目(我制作了 sqlite 来保存收藏夹)现在我想在我打开 Activity 时让 RecyclerView 显示带有不同图像的 ImageButton 如果它在收藏夹中并且当按下它改变图像 只是我想制作像 gmail 应用程序一样的收藏按钮(星形图像)

RecyclerView 适配器

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder> {

Context context;
List<listitem_gib> getDataAdapter;



public RecyclerViewAdapter(List<listitem_gib> getDataAdapter, Context context){

    super();

    this.getDataAdapter = getDataAdapter;
    this.context = context;

}

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardview_layout, parent, false);

    ViewHolder viewHolder = new ViewHolder(v,context,getDataAdapter);

    return viewHolder;
}

@Override
public void onBindViewHolder(ViewHolder holder, final int position) {

    listitem_gib getDataAdapter1 =  getDataAdapter.get(position);

    holder.name.setText(getDataAdapter1.getName());
    holder.num.setText(getDataAdapter1.getnum());
    Picasso.with(context).load("http://grassyhat.com/android/image/" + getDataAdapter1.getimg()).into(holder.img1);

    holder.fav.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            fav(position);
        }
    });

}

@Override
public int getItemCount() {

    return getDataAdapter.size();
}

class ViewHolder extends RecyclerView.ViewHolder
            implements View.OnClickListener{

    public TextView name;
    public TextView num;
    public ImageView img1;

    ImageButton fav;

    Context context;
    List<listitem_gib> getDataAdapter;


    public ViewHolder(View itemView, Context context ,List<listitem_gib> getDataAdapter ) {

        super(itemView);
        itemView.setOnClickListener(this);
        this.getDataAdapter = getDataAdapter;
        this.context = context;
        this.fav= (ImageButton) itemView.findViewById(R.id.btn_fav);

        name = (TextView) itemView.findViewById(R.id.Main_Text) ;
        num = (TextView) itemView.findViewById(R.id.Second_Text) ;
        img1 = (ImageView) itemView.findViewById(R.id.img1) ;

    }


    @Override
    public void onClick(View v) {

        int position = getAdapterPosition();
        listitem_gib getDataAdapter =this.getDataAdapter.get(position);
        Intent intent = new Intent(this.context,Rewaya_info.class);
        intent.putExtra("name",getDataAdapter.getName());
        intent.putExtra("url",getDataAdapter.geturl());
        intent.putExtra("img",getDataAdapter.getimg());
        intent.putExtra("num",getDataAdapter.getnum());
        intent.putExtra("size",getDataAdapter.getsize());
        this.context.startActivity(intent);

    }
}



public void fav(final int position) {
    final DB_Sqlit db_sqlit = new DB_Sqlit(context);
    final String name = getDataAdapter.get(position).name;
    final String img = getDataAdapter.get(position).img;
    final String url = getDataAdapter.get(position).url;
    final String num = getDataAdapter.get(position).num;
    final String size = getDataAdapter.get(position).size;

    int count = db_sqlit.get_check_List_Favorite(name);
    if (count > 0) {
        Toast.makeText(context, "already exist", Toast.LENGTH_SHORT).show();
    }else{
        Boolean add = db_sqlit.Insert_to_favorite(name, img, url, num, size);
        if (add) {
            Toast.makeText(context, "added to favourite", Toast.LENGTH_SHORT).show();
        } else {
            Toast.makeText(context, "error", Toast.LENGTH_SHORT).show();
        }

    }
}

数据库

public class DB_Sqlit extends SQLiteOpenHelper {

public static final String BDname = "mdata.db";

public DB_Sqlit(Context context) {
    super(context, BDname, null, 1);
}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL("create table favorite ( id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, img TEXT, url TEXT, num TEXT, size TEXT)");
        }

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXISTS favorite");
    onCreate(db);

}



public Boolean Insert_to_favorite(String name, String img, String url, String num, String size) {
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put("name", name);
    contentValues.put("img", img);
    contentValues.put("url", url);
    contentValues.put("num", num);
    contentValues.put("size", size);


    long result = db.insert("favorite", null, contentValues);

    if (result == -1)
        return false;
    else
        return true;

}


public List getAllList_Favorite() {
    List<listitem_gib> list = new ArrayList<listitem_gib>();
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor rs = db.rawQuery("select * from favorite", null);

    if (rs.moveToFirst()){
        do {
            listitem_gib model = new listitem_gib();
            model.setId(rs.getString(0));
            model.setName(rs.getString(1));
            model.seturl(rs.getString(3));
            model.setimg(rs.getString(2));
            model.setnum(rs.getString(4));
            model.setsize(rs.getString(5));

            list.add(model);
        }while (rs.moveToNext());
    }
    Log.d("rewayat data", list.toString());
    return list;
}


public int get_check_List_Favorite(String Title) {

    SQLiteDatabase db = this.getReadableDatabase();
    Cursor rs = db.rawQuery("select * from favorite Where name like '"+ Title +"'", null);
    rs.moveToFirst();
    int count = rs.getCount();
    return count;
}


public Integer DeleteFav(String id) {
    SQLiteDatabase db = this.getWritableDatabase();
    return db.delete("favorite", "id = ?", new String[]{id});
}

卡片布局

<android.support.v7.widget.CardView
    android:layout_width="130dp"
    android:layout_height="225dp"
    app:cardElevation="15dp"
    app:cardBackgroundColor="#eae7cb7c"
    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    app:cardCornerRadius="8dp"
    android:layout_marginLeft="16dp"
    android:layout_marginStart="16dp"
    android:layout_marginTop="16dp"
    android:layout_marginBottom="16dp">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <FrameLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content">

        <ImageView
            android:id="@+id/img1"
            android:layout_width="130dp"
            android:layout_height="130dp"
            android:layout_gravity="center"
            android:scaleType="centerCrop"/>

            <FrameLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/delete"
                android:layout_gravity="end">

                <ImageButton
                    android:id="@+id/btn_fav"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:src="@android:drawable/btn_star"
                    android:background="#00ffffff"
                    android:layout_marginTop="5dp"
                    android:layout_marginLeft="5dp"/>

            </FrameLayout>

        </FrameLayout>


        <TextView
            android:id="@+id/Main_Text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Label"
            android:layout_gravity="right"
            android:textSize="15sp"
            android:padding="5dp"
            android:layout_marginTop="5dp"
            android:textColor="#6a9399"/>

        <TextView
            android:id="@+id/Second_Text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="LongerLabel"
            android:layout_gravity="right"
            android:textSize="12sp"
            android:padding="5dp"
            android:textStyle="bold"
            android:textColor="#998c6a"/>

    </LinearLayout>

</android.support.v7.widget.CardView>

Answer 1

在您的 onBindViewHolder 中，您可以根据需要切换图像。

holder.fav.setOnClickListener(new View.OnClickListener(){
    @Override
    public void onClick(View v) {
        if(holder.fav.getTag() == R.drawable.fav_icon) {
            unfav(position);
            holder.fav.setImageResource(R.drawable.unfav_icon);
            holder.fav.setTag(R.drawable.unfav_icon);
        }
        else {
            fav(position);
            holder.fav.setImageResource(R.drawable.fav_icon);
            holder.fav.setTag(R.drawable.fav_icon);
        }
    }
});

在您的 onBindViewHolder() 方法中，您可以添加初始状态:

if(holder.fav.getTag() == R.drawable.fav_icon)
    holder.fav.setImageResource(R.drawable.fav_icon);
else
    holder.fav.setImageResource(R.drawable.unfav_icon);