如何使用recyclelerview和databse在android中将位置明智的对象数据传递给另一个
我创建了recycerview，这个recycerview显示了Person图像，人名和+按钮，当我按下+按钮更改按钮图像时就像是true。在recycerview底部一个按钮后，这个按钮点击所有数据显示下一个活动..
我的适配器
public class BuildCustomAdapter extends RecyclerView.Adapter implements Filterable { private List peopleList; private List peopleListCopy; private ItemFilter mFilter = new ItemFilter(); public BuildCustomAdapter(List buildList) { this.peopleList = buildList; this.peopleListCopy = new ArrayList(); peopleListCopy.addAll(buildList); } @Override public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View itemView = LayoutInflater.from(parent.getContext()) .inflate(R.layout.build_list_row, parent, false); return new MyViewHolder(itemView); } @Override public void onBindViewHolder(final MyViewHolder holder, final int position) { People people = peopleList.get(position); byte[] decodedString = Base64.decode(people.getPeopleImage(), Base64.DEFAULT); Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length); holder.ivPeopleImage.setImageBitmap(decodedByte); holder.tvPersonName.setText(people.getPeopleName()); holder.button.setSelected(people.isSelected()); holder.button.setOnClickListener(new onSelectListener(position)); } @Override public int getItemCount() { return peopleList.size(); } @Override public Filter getFilter() { if (mFilter == null) { mFilter = new ItemFilter(); } return mFilter; } public class MyViewHolder extends RecyclerView.ViewHolder { // public ImageView ivPeopleImage; public TextView tvPersonName; public Button button; public CircularImageView ivPeopleImage; public MyViewHolder(View itemView) { super(itemView); ivPeopleImage = (CircularImageView) itemView.findViewById(R.id.ivPerson); tvPersonName = (TextView) itemView.findViewById(R.id.tvPersonName); button = (Button) itemView.findViewById(R.id.addbn); } } private class ItemFilter extends Filter { protected FilterResults performFiltering(CharSequence constraint) { FilterResults results = new FilterResults(); if (constraint != null && constraint.length() > 0) { List filterList = new ArrayList(); for (int i = 0; i < peopleListCopy.size(); i++) { if ((peopleListCopy.get(i).getPeopleName().toUpperCase()) .contains(constraint.toString().toUpperCase())) { People peopleName = peopleListCopy.get(i); filterList.add(peopleName); } } results.count = filterList.size(); results.values = filterList; } else { results.count = peopleListCopy.size(); results.values = peopleListCopy; } return results; } @Override protected void publishResults(CharSequence constraint, FilterResults results) { peopleList = (List) results.values; notifyDataSetChanged(); } } private class onSelectListener implements View.OnClickListener { int mPosition; public onSelectListener(int position) { mPosition = position; } @Override public void onClick(View view) { view.setSelected(!view.isSelected()); People people = peopleList.get(mPosition); people.setSelected(!people.isSelected()); notifyDataSetChanged(); } } 活动
public class BulidActivity extends AppCompatActivity { private List peopleList = new ArrayList(); private List peopleListCopy = new ArrayList(); private RecyclerView recyclerView; private BuildCustomAdapter buildCustomAdapter; protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_bulid); getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN); BuildData(); peopleListCopy.addAll(peopleList); recyclerView = (RecyclerView) findViewById(R.id.recycler_view); buildCustomAdapter = new BuildCustomAdapter(peopleList); RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext()); recyclerView.setLayoutManager(mLayoutManager); recyclerView.setItemAnimator(new DefaultItemAnimator()); recyclerView.setAdapter(buildCustomAdapter); AddTxt(); BtnBuildNow(); } private void BtnBuildNow() { Button btnnuildnow = (Button) findViewById(R.id.btn_build_now); btnnuildnow.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent intent = new Intent(BulidActivity.this, AlertList.class); startActivity(intent); } }); } private void AddTxt() { EditText editTxt = (EditText) findViewById(R.id.etSearch); editTxt.setTextColor(Color.WHITE); editTxt.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { v.setFocusable(true); v.setFocusableInTouchMode(true); return false; } }); editTxt.addTextChangedListener(new TextWatcher() { public void onTextChanged(CharSequence s, int start, int before, int count) { if (s.length() <= 0) { peopleList.clear(); peopleList.addAll(peopleListCopy); recyclerView.setAdapter(null); buildCustomAdapter = new BuildCustomAdapter(peopleList); recyclerView.setAdapter(buildCustomAdapter); } else { buildCustomAdapter.getFilter().filter(s.toString()); } } @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { } @Override public void afterTextChanged(Editable s) { } }); } private List BuildData() { DataBaseHelper db = new DataBaseHelper(getApplicationContext()); try { db.createDataBase(); } catch (IOException ioe) { throw new Error("Unable to create database"); } if (db.open()) { peopleList = db.getPeople(); } return peopleList; }
模特课
public class People implements Serializable { private String peopleImage; private String peopleName; private boolean selected; public void setPeopleName(String peopleName) { this.peopleName = peopleName; } public String getPeopleName() { return peopleName; } public void setPeopleImage(String peopleImage) { this.peopleImage = peopleImage; } public String getPeopleImage() { return peopleImage; } public boolean isSelected() { return selected; } public void setSelected(boolean selected) { this.selected = selected; }
DatabaseHelper.class
public class DataBaseHelper extends SQLiteOpenHelper { private static final String DB_PATH = "/data/data/databasename/databases/"; private static final String DB_NAME = "alertme.db"; private final String TABLE_PEOPLE = "people"; private final String TABLE_CATEGORY = "category"; private final String CATEGORY_NAME = "name"; private final String ID = "id"; private final String CATEGORY_ID = "category_id"; private final String PEOPLE_IMAGE = "image"; private final String PEOPLE_NAME = "name"; private SQLiteDatabase myDataBase; private final Context myContext; public DataBaseHelper(Context context) { super(context, DB_NAME, null, 1); this.myContext = context; } public void createDataBase() throws IOException { boolean dbExist = checkDataBase(); if (dbExist) { } else { this.getReadableDatabase(); try { copyDataBase(); } catch (IOException e) { throw new Error("Error copying database"); } } } private boolean checkDataBase() { SQLiteDatabase checkDB = null; try { String myPath = DB_PATH + DB_NAME; checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); } catch (SQLiteException e) { } if (checkDB != null) { checkDB.close(); } return checkDB != null ? true : false; } private void copyDataBase() throws IOException { InputStream myInput = myContext.getAssets().open(DB_NAME); String outFileName = DB_PATH + DB_NAME; OutputStream myOutput = new FileOutputStream(outFileName); byte[] buffer = new byte[1024]; int length; while ((length = myInput.read(buffer)) > 0) { myOutput.write(buffer, 0, length); } myOutput.flush(); myOutput.close(); myInput.close(); } public boolean open() { try { String myPath = DB_PATH + DB_NAME; myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE); return true; } catch (SQLException sqle) { myDataBase = null; return false; } } public List getPeople(String category_id) { List peoples = new ArrayList(); try { SQLiteDatabase db = SQLiteDatabase.openDatabase(DB_PATH + DB_NAME, null, SQLiteDatabase.OPEN_READWRITE); Cursor cursor = db.rawQuery("select * from people where category_id = " + category_id, null); while (cursor.moveToNext()) { String peopleName = cursor.getString(cursor.getColumnIndex(PEOPLE_NAME)); String peopleImage = cursor.getString(cursor.getColumnIndex(PEOPLE_IMAGE)); People people = new People(); people.setPeopleName(peopleName); people.setPeopleImage(peopleImage); peoples.add(people); } } catch (Exception e) { Log.d("DB", e.getMessage()); } return peoples; } public List getCategory() { List categoryList = new ArrayList(); try { String query = " SELECT * FROM " + TABLE_CATEGORY; SQLiteDatabase db = SQLiteDatabase.openDatabase(DB_PATH + DB_NAME, null, SQLiteDatabase.OPEN_READWRITE); Cursor cursor = db.rawQuery(query, null); while (cursor.moveToNext()) { int categoryID = cursor.getInt(cursor.getColumnIndex(ID)); String categoryName = cursor.getString(cursor.getColumnIndex(CATEGORY_NAME)); Category category = new Category(); category.setId(categoryID); category.setCategoryName(categoryName); categoryList.add(category); } } catch (Exception e) { Log.d("DB", e.getMessage()); } return categoryList; } @Override public synchronized void close() { if (myDataBase != null) myDataBase.close(); super.close(); } @Override public void onCreate(SQLiteDatabase db) { } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { }
在下面的方法中添加意图，
holder.button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { build.setSelected(!build.isSelected()); if (build.isSelected()) { holder.button.setBackgroundResource(R.drawable.selected_true_icon_new); Intent intent = new Intent(context, youractivity.class) intenet.putExtra("key","value"); context.startActivity(intent); } else holder.button.setBackgroundResource(R.drawable.add_button_icon); } });
您注册ViewHolder上的click事件的巨大错误！ 你会从实际中获得不同的位置，因为当android使用notifyItemMoved时，不会调用viewBindHolder而你的位置错误。
在click监听器实现中，您应该将Intent传递给您的数据
首先，您应该在Build模型类中实现Serializable接口，如下所示： –
public class Build implements Serializable{ //Content will be as it is }
像这样更改clickListener： –
holder.button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { build.setSelected(!build.isSelected()); if (build.isSelected()) { holder.button.setBackgroundResource(R.drawable.selected_true_icon_new); Intent intent = new Intent(context, youractivity.class) intenet.putExtra("build",build); context.startActivity(intent); } else holder.button.setBackgroundResource(R.drawable.add_button_icon); } });
在onCreate接收活动的方法写这个： –
Build build = (Build) getIntent().getSerializableExtra("build");