即使在wrapcontent中，我的cardview也会离开屏幕

Question

我的问题-

我的cardview正在屏幕上显示（可以在图像中看到），即使上面说的是matchparent。

我的数据库节点请帮助。。。。。。。这是bug还是smth？

我在做什么=我正在尝试在回收器视图中从firebase检索数据，正在检索数据，但回收器视图的项目出现问题，因为cardview在屏幕外有一半，即使cardview设置为matchparent和wrapcontent，请尽可能提供帮助

我的回收项目

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
    android:id="@+id/Cdate"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Hi"
    android:textSize="50dp"
    android:layout_gravity="center"
    android:layout_marginTop="20dp"/>
    </androidx.cardview.widget.CardView>

我的Adapterclass

package com.sjsbhints.pdfmanager;

  import android.view.LayoutInflater;
   import android.view.View;
     import android.view.ViewGroup;
     import android.widget.TextView;

    import androidx.annotation.NonNull;
    import androidx.recyclerview.widget.RecyclerView;

  import com.firebase.ui.database.FirebaseRecyclerAdapter;
  import com.firebase.ui.database.FirebaseRecyclerOptions;

  public class CAdapter extends FirebaseRecyclerAdapter<Cmodel,CAdapter.myViewHolder> {

/**
 * Initialize a {@link RecyclerView.Adapter} that listens to a Firebase query. See
 * {@link FirebaseRecyclerOptions} for configuration options.
 *
 * @param options
 */
public CAdapter(@NonNull FirebaseRecyclerOptions<Cmodel> options) {
    super(options);
}

@Override
protected void onBindViewHolder(@NonNull myViewHolder holder, int position, @NonNull Cmodel model) {

  //         if(model.Cdate.isEmpty()){
     //             holder.Cdate.setText("Null");
       //         }
        holder.Cdate.setText(model.getCdate());
     //        holder.Cheading.setText(model.getCheading());
     //       holder.Cbody.setText(model.getCbody());

}

@NonNull
@Override
public myViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.circular_item,parent,false);

    return new myViewHolder(view);
}

class myViewHolder extends RecyclerView.ViewHolder{

    TextView Cdate,Cheading,Cbody,Ndate,Nheading,Nsheading,Nbody,Tdate,Tsubject,Ttopic,Ttdate;

    public myViewHolder(@NonNull View itemView) {
        super(itemView);

          Cdate = itemView.findViewById(R.id.Cdate);
    //            Cheading = itemView.findViewById(R.id.cheading);
  //            Cbody = itemView.findViewById(R.id.cbody);
                }
               }
                }

我的模型类

package com.sjsbhints.pdfmanager;

public class Cmodel {

String Cdate,Cheading,Cbody,Ndate,Nheading,Nsheading,Nbody,Tdate,Tsubject,Ttopic,Ttdate;

Cmodel(){
}

public Cmodel(String cdate, String cheading, String cbody, String ndate, String nheading, String nsheading, String nbody, String tdate, String tsubject, String ttopic, String ttdate) {
    Cdate = cdate;
    Cheading = cheading;
    Cbody = cbody;
    Ndate = ndate;
    Nheading = nheading;
    Nsheading = nsheading;
    Nbody = nbody;
    Tdate = tdate;
    Tsubject = tsubject;
    Ttopic = ttopic;
    Ttdate = ttdate;
}

public String getCdate() {
    return Cdate;
}

public void setCdate(String cdate) {
    Cdate = cdate;
}

public String getCheading() {
    return Cheading;
}

public void setCheading(String cheading) {
    Cheading = cheading;
}

public String getCbody() {
    return Cbody;
}

public void setCbody(String cbody) {
    Cbody = cbody;
}

public String getNdate() {
    return Ndate;
}

public void setNdate(String ndate) {
    Ndate = ndate;
}

public String getNheading() {
    return Nheading;
}

public void setNheading(String nheading) {
    Nheading = nheading;
}

public String getNsheading() {
    return Nsheading;
}

public void setNsheading(String nsheading) {
    Nsheading = nsheading;
}

public String getNbody() {
    return Nbody;
}

public void setNbody(String nbody) {
    Nbody = nbody;
}

public String getTdate() {
    return Tdate;
}

public void setTdate(String tdate) {
    Tdate = tdate;
}

public String getTsubject() {
    return Tsubject;
}

public void setTsubject(String tsubject) {
    Tsubject = tsubject;
}

public String getTtopic() {
    return Ttopic;
}

public void setTtopic(String ttopic) {
    Ttopic = ttopic;
}

public String getTtdate() {
    return Ttdate;
}

public void setTtdate(String ttdate) {
    Ttdate = ttdate;
}
}

我的主要活动

       package com.sjsbhints.pdfmanager;

          import androidx.annotation.Nullable;
        import androidx.appcompat.app.AppCompatActivity;
          import androidx.recyclerview.widget.LinearLayoutManager;
        import androidx.recyclerview.widget.RecyclerView;

         import android.os.Bundle;

           import com.firebase.ui.database.FirebaseRecyclerOptions;
          import com.google.firebase.database.FirebaseDatabase;

   public class CircularAct extends AppCompatActivity {

RecyclerView recyclerView;
CAdapter cAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_circular2);

    recyclerView = findViewById(R.id.rv);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));



    FirebaseRecyclerOptions<Cmodel> options =
            new FirebaseRecyclerOptions.Builder<Cmodel>()
                    .setQuery(FirebaseDatabase.getInstance().getReference().child("CircularData"), Cmodel.class)
                    .build();

    cAdapter = new CAdapter(options);
    recyclerView.setAdapter(cAdapter);

}


@Override
protected void onStart() {
    super.onStart();
    cAdapter.startListening();
}

@Override
protected void onStop() {
    super.onStop();
    cAdapter.stopListening();
}
}

我的主要活动Xml

   <?xml version="1.0" encoding="utf-8"?>
      <androidx.constraintlayout.widget.ConstraintLayout 
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
     tools:context=".CircularAct">

     <androidx.recyclerview.widget.RecyclerView
    android:id="@+id/rv"
    android:layout_width="599dp"
    android:layout_height="960dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />
    </androidx.constraintlayout.widget.ConstraintLayout>

Answer 1

您的CardView与父视图的宽度完全匹配，因为它继承了RecyclerView的宽度，因为它是其父视图。

另一方面，回收站视图的宽度为599dp。固定大小意味着它将忽略设备的宽度。要匹配设备的宽度和高度，请将其设置为match_parent或使用0dp，因为您在案例中使用了约束布局。

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/rv"
    android:layout_width="0dp"
    android:layout_height="0dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />
    </androidx.constraintlayout.widget.ConstraintLayout>