我想要一个recyclerview只显示一个数组,但是在arraylist中有更多的数组。必须显示的数字不一定总是相同的,但这将取决于某些百分比。
例如:第一个阵列有20%的机会,第二个50%和第三个50%的机会。并随机显示一个。但是,当我刷新屏幕时,它将改变。
我想我应该做的是为arraylist上的每个单个数组设置百分比,但是我不知道该怎么做以及下一步该怎么做。
那是我的java文件。
public class Comida extends AppCompatActivity implements Adaptador2.OnRecipeListener {
private RecyclerView recyclerView1;
List<Entidad2> listItems;
Adaptador2 adaptor;
private Entidad2 entidad1,entidad2,entidad3;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_comida);
recyclerView1 = findViewById(R.id.lv_1);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView1.setLayoutManager(layoutManager);
listItems = new ArrayList<>();
entidad1 = new Entidad2(R.drawable.calabacines_3, "Solomillo a la plancha", " 10 min.", 4, 20);
entidad2 = new Entidad2(R.drawable.patatas_deluxe_especiadas_70523_300_150, "Entrecot", " 15 min.", 2, 50);
entidad3 = new Entidad2(R.drawable.tomate, "Hamburguesa", " 2 min.", 5, 100);
listItems.add(entidad1);
listItems.add(entidad2);
listItems.add(entidad3);
adaptor = new Adaptador2(listItems, this);
recyclerView1.setAdapter(adaptor);
adaptor.notifyDataSetChanged();
pickEntidad();
}
@Override
public void OnRecipe(int priority) {
if (priority == 20) {
Intent in = new Intent(this, Solomillo.class);
startActivity(in);
}
if (priority == 50) {
Intent in = new Intent(this, Entrecot.class);
startActivity(in);
}
if (priority == 100) {
Intent in = new Intent(this, Hamburguesa.class);
startActivity(in);
}
}
private void pickEntidad(){
final int random = new Random().nextInt(101);
int priority1 = entidad1.getPriority();
int priority2 = entidad2.getPriority();
int priority3 = entidad3.getPriority();
listItems.clear();
if(random < priority1){
listItems.add(entidad1);
}else if(random < priority2){
listItems.add(entidad2);
}else if (random <= priority3){
listItems.add(entidad3);
}
adaptor.notifyDataSetChanged();
}
}
那就是适配器:
public class Adaptador extends RecyclerView.Adapter<Adaptador.ViewHolder> //implements View.OnClickListener
{
private List<Entidad> listItems;
private OnRecipeListener mOnRecipeListener;
public Adaptador(List<Entidad> listItems, OnRecipeListener onRecipeListener) {
this.listItems = listItems;
this.mOnRecipeListener = onRecipeListener;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.elemento_lista, parent, false);
//view.setOnClickListener(this);
return new ViewHolder(view, mOnRecipeListener);
}
@Override
public void onBindViewHolder(ViewHolder viewholder, int position) {
int resource = listItems.get(position).getImgFoto();
String title = listItems.get(position).getTitulo();
String time = listItems.get(position).getTiempo();
int barra = listItems.get(position).getRating();
int fondo = listItems.get(position).getColorfondo();
viewholder.setData(resource, title, time, barra, fondo);
}
@Override
public int getItemCount() {
return listItems.size();
}
class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private ImageView imgFoto;
private TextView titulo;
private TextView tiempo;
private RatingBar ratingBar;
private ImageView colorfondo;
OnRecipeListener onRecipeListener;
public ViewHolder(View itemView, OnRecipeListener onRecipeListener) {
super(itemView);
imgFoto = itemView.findViewById(R.id.imgFoto);
titulo = itemView.findViewById(R.id.tvTitulo);
tiempo = itemView.findViewById(R.id.tvTiempo);
ratingBar = itemView.findViewById(R.id.ratingBarVerd);
colorfondo = itemView.findViewById(R.id.colorfondo);
this.onRecipeListener = onRecipeListener;
itemView.setOnClickListener(this);
}
private void setData(int resource, String title, String time, int barra, int fondo){
imgFoto.setImageResource(resource);
titulo.setText(title);
tiempo.setText(time);
ratingBar.setRating(barra);
colorfondo.setImageResource(fondo);
}
@Override
public void onClick(View v) {
onRecipeListener.OnRecipe(getAdapterPosition());
}
}
public interface OnRecipeListener{
void OnRecipe(int position);
}
}
这里是Entidad文件:
public class Entidad2 {
private int imgFoto;
private String titulo;
private String tiempo;
private int ratingBar;
private int colorfondo;
public Entidad2(int imgFoto, String titulo, String tiempo, int ratingBar, int colorfondo) {
this.imgFoto = imgFoto;
this.titulo = titulo;
this.tiempo = tiempo;
this.ratingBar = ratingBar;
this.colorfondo = colorfondo;
}
public int getImgFoto() {
return imgFoto;
}
public String getTitulo() {
return titulo;
}
public String getTiempo() {
return tiempo;
}
public int getRating() { return ratingBar; }
public int getColorfondo() {
return colorfondo;
}
}
如果有人对如何操作有任何想法,请告诉我。
如果您需要更多代码,请告诉我,
谢谢。
enter image description here
在这里@Emir看看是否在里面
public class Comida extends AppCompatActivity implements Adaptador2.OnRecipeListener {
private RecyclerView recyclerView1;
List<Entidad2> listItems;
private Entidad2 entidad1,entidad2,entidad3;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_comida);
recyclerView1 = findViewById(R.id.lv_1);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView1.setLayoutManager(layoutManager);
listItems = new ArrayList<>();
entidad1 = new Entidad2(R.drawable.calabacines_3, "Solomillo a la plancha", " 10 min.", 4, R.drawable.color_carnes, 50));
entidad2 = new Entidad2(R.drawable.patatas_deluxe_especiadas_70523_300_150, "Entrecot", " 15 min.", 2, R.drawable.color_carnes, 200));
entidad3 = new Entidad2(R.drawable.tomate, "Hamburguesa", " 2 min.", 5, R.drawable.color_carnes, 350));
listItems.add(entidad1);
listItems.add(entidad2);
listItems.add(entidad3);
Adaptador2 Adaptador2 = new Adaptador2(listItems, this);
recyclerView1.setAdapter(Adaptador2);
Adaptador2.notifyDataSetChanged();
pickEntidad();
}
@Override
public void OnRecipe(int position) {
if (position == 0) {
Intent in = new Intent(this, Solomillo.class);
startActivity(in);
}
}
private void pickEntidad(){
final int random = new Random().nextInt(351);
int priority1 = entidad1.getPriority();
int priority2 = entidad2.getPriority();
int priority3 = entidad3.getPriority();
listItems.clear();
if(random < priority1){
listItems.add(entidad1);
}else if(random < priority2){
listItems.add(entidad2);
}else if (random <= priority3){
listItems.add(entidad3);
}
Adaptador2.notifyDataSetChanged();
}
}
最佳答案
我的理解是,您想从Entidad列表中随机显示一个Entidad对象,且机会不同。
例如:在Entidad对象上创建一个名为Priority的整数字段。将第一个Entidad的优先级设置为50,第二个为200,第三个为350.创建以下方法以根据优先级随机选择(创建对象后,将其对Entidad对象的引用保存在mainactivity中)。
编辑:Entidad.java
public class Entidad {
private int imgFoto;
private String titulo;
private String tiempo;
private int ratingBar;
private int colorfondo;
private int priority;
public Entidad(int imgFoto, String titulo, String tiempo, int ratingBar, int colorfondo, int priority) {
this.imgFoto = imgFoto;
this.titulo = titulo;
this.tiempo = tiempo;
this.ratingBar = ratingBar;
this.colorfondo = colorfondo;
this.priority = priority;
}
public int getRatingBar() {
return ratingBar;
}
public int getPriority() {
return priority;
}
public int getImgFoto() {
return imgFoto;
}
public String getTitulo() {
return titulo;
}
public String getTiempo() {
return tiempo;
}
public int getRating() { return ratingBar; }
public int getColorfondo() {
return colorfondo;
}
}
编辑2:使用getEntidad()
public class Comida extends AppCompatActivity implements Adaptador.OnRecipeListener {
private RecyclerView recyclerView1;
List<Entidad> listItems;
Adaptador adaptor;
private Entidad entidad1,entidad2,entidad3;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_comida);
recyclerView1 = findViewById(R.id.lv_1);
LinearLayoutManager layoutManager = new
LinearLayoutManager(this);
layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
recyclerView1.setLayoutManager(layoutManager);
listItems = new ArrayList<>();
//Initialize entidad objects and keep references of them to use in pickEntidad() method
entidad1 = new Entidad(R.drawable.calabacines_3, "Solomillo a la plancha", " 10 min.", 4, R.drawable.color_carnes,50);
entidad2 = new Entidad(R.drawable.patatas_deluxe_especiadas_70523_300_150, "Entrecot", " 15 min.", 2, R.drawable.color_carnes,200);
entidad3 = new Entidad(R.drawable.tomate, "Hamburguesa", " 2 min.", 5, R.drawable.color_carnes,350);
listItems.add(entidad1);
listItems.add(entidad2);
listItems.add(entidad3);
adaptor = new Adaptador(listItems, this);
recyclerView1.setAdapter(adaptador);
adaptor.notifyDataSetChanged();
//Call pickEntidad() to randomly pick one entidad and show on the list
pickEntidad();
}
@Override
public void OnRecipe(int position) {
if (position == 0) {
Intent in = new Intent(this, Solomillo.class);
startActivity(in);
}
}
private void pickEntidad(){
//Generates random int value between 0-350
final int random = new Random().nextInt(351);
//get priorities from your created Entidad objects.
int priority1 = entidad1.getPriority();
int priority2 = entidad2.getPriority();
int priority3 = entidad3.getPriority();
listItems.clear()
//Pick one randomly depending on priority
if(random < priority1){
listItems.add(entidad1)
}else if(random < priority2){
listItems.add(entidad2)
}else if (random <= priority3){
listItems.add(entidad3)
}
//update your adapter
adaptor.notifyDataSetChanged()
}
}
每次您要刷新列表时,都调用此pickEntidad()方法。但是,这是一种硬编码的方法,如果您有太多的项目并且不知道优先级值或范围,那将是无用的。您还可以通过在0-351之间生成一个整数来随机设置项目优先级。希望我能正确理解您的问题。
另外,不要给变量名称加上大写字母后者。将您的“适配器”变量更改为“适配器”