Android Studio Recycler View在行之间有间隙.帮我修

Question

我在youtube上为我的学校项目学习了这个教程。该应用程序能够从画廊中显示选定的图像，但回收器视图在每一行都有空白。我写什么代码来修复这个应用程序?的帮助。输入图片描述

这是我的activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
android:orientation="vertical"
android:scrollbarStyle="insideInset"
android:scrollbars="vertical"
tools:context=".MainActivity">
<Button
android:id="@+id/pick"
android:layout_width="53dp"
android:layout_height="64dp"
android:layout_margin="12dp"
android:layout_weight="0"
android:backgroundTint="#FF5722"
android:text="+"
android:textSize="24sp"
app:cornerRadius="64dp" />
<TextView
android:id="@+id/totalPhotos"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0"
android:gravity="center"
android:textColor="#FFFFFF" />
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recyclerView_Gallery_Images"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:layout_weight="1"

</LinearLayout>

RecyclerAdapter.java

package com.example.mygram;
import android.media.Image;
import android.net.Uri;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.ViewHolder> {
private ArrayList<Uri> uriArrayList;
public RecyclerAdapter(ArrayList<Uri> uriArrayList) {
this.uriArrayList = uriArrayList;
}
@NonNull
@Override
public RecyclerAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View view = inflater.inflate(R.layout.custom_single_image,parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull RecyclerAdapter.ViewHolder holder, int position) {
holder.imageView.setImageURI(uriArrayList.get(position));
}
@Override
public int getItemCount() {
return uriArrayList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
ImageView imageView;
public ViewHolder(@NonNull View itemView) {
super(itemView);
imageView = itemView.findViewById(R.id.image);
}
}
}

自定义single images.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<ImageView
android:id="@+id/image"
android:layout_width="match_parent"
android:layout_height="0dp"
android:scaleType="centerCrop"
app:layout_constraintDimensionRatio="1"
tools:ignore="MissingConstraints" />
</androidx.constraintlayout.widget.ConstraintLayout>

这里是mainactivity。java

package com.example.mygram;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;
import androidx.recyclerview.widget.GridLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
RecyclerView recyclerView;
TextView textView;
Button pick;
ArrayList <Uri> uri = new ArrayList<>();
RecyclerAdapter adapter ;
private static final int Read_Permission = 101;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textView = findViewById(R.id.totalPhotos);
recyclerView = findViewById(R.id.recyclerView_Gallery_Images);
pick = findViewById(R.id.pick);
adapter = new RecyclerAdapter(uri);
recyclerView.setLayoutManager(new GridLayoutManager(MainActivity.this,3));
recyclerView.setAdapter(adapter);
if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, Read_Permission);
}

pick.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent();
intent.setType("image/*");
if  (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2){
intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);
}
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"), 1);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == 1 && resultCode == Activity.RESULT_OK){
if(data.getClipData() !=null) {
int x = data.getClipData().getItemCount();
for (int i = 0; i < x; i++) {
uri.add(data.getClipData().getItemAt(i).getUri());
}
adapter.notifyDataSetChanged();
textView.setText("Photos ("+uri.size()+")");
}else if (data.getData()!=null){
String imageURL=data.getData().getPath();
uri.add(Uri.parse(imageURL));
}
}
}
}

这个应用程序的概念是instagram feed tester。我希望能够像在instagram上的网格一样显示图像，但差距正在出现，防止它发生。请帮帮我，谢谢。

Answer 1

在Custom single images.xml将父布局的高度替换为wrap_content。用下面的

替换你的代码

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<ImageView
android:id="@+id/image"
android:layout_width="match_parent"
android:layout_height="0dp"
android:scaleType="centerCrop"
app:layout_constraintDimensionRatio="1"
tools:ignore="MissingConstraints" />
</androidx.constraintlayout.widget.ConstraintLayout>

Answer 2

一切正常:只需将this改为this:(images.xml)

android:layout_height="match_parent"

android:layout_height="wrap_content"

在你的模型XML文件