问题
I have create the recycerview and this recycerview display the Person image ,person name and + button when i have press + button change the button image like true.and after recycerview bottom one button this button click all data show the next activity..
My Adapter
public class BuildCustomAdapter extends RecyclerView.Adapter<BuildCustomAdapter.MyViewHolder> implements Filterable {
private List<People> peopleList;
private List<People> peopleListCopy;
private ItemFilter mFilter = new ItemFilter();
public BuildCustomAdapter(List<People> 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<People> 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<People>) 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();
}
}
Activity
public class BulidActivity extends AppCompatActivity {
private List<People> peopleList = new ArrayList<>();
private List<People> 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<People> 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;
}
Model class
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<People> getPeople(String category_id) {
List<People> 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<Category> getCategory() {
List<Category> 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) {
}
回答1:
Add Intent in below Method,
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);
}
});
回答2:
First you should implement Serializable interface in your Build model class like this :-
public class Build implements Serializable{
//Content will be as it is
}
Change your clickListener like this :-
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);
}
});
In the onCreate method of receiving activity write this :-
Build build = (Build) getIntent().getSerializableExtra("build");
回答3:
Huge mistak that you register to the click event on your ViewHolder! you will get diffrent position from the actual because when android use notifyItemMoved the viewBindHolder will not be called and than you got the wrong position.
and in the click listener implementation you should pass Intent with your data
来源：https://stackoverflow.com/questions/39746341/how-to-pass-position-wise-object-data-one-activity-to-another-using-recyclerview