Java 如何在gridview中显示图像
我想显示drawble中的图像,但我的应用程序在运行时出现问题,gtidview无法显示图像,所以我需要所有人的帮助 这是我的班级 MinhAcivity.javaJava 如何在gridview中显示图像,java,android,image,gridview,Java,Android,Image,Gridview,我想显示drawble中的图像,但我的应用程序在运行时出现问题,gtidview无法显示图像,所以我需要所有人的帮助 这是我的班级 MinhAcivity.java public class MinhActivity extends Activity { GridView gridView; int categoryImages[] ={R.drawable.android1,R.drawable.android2,R.drawable.android3,R.drawable.a
public class MinhActivity extends Activity {
GridView gridView;
int categoryImages[] ={R.drawable.android1,R.drawable.android2,R.drawable.android3,R.drawable.android4, R.drawable.android5, R.drawable.android6};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_minh);
gridView = findViewById(R.id.grView_categories);
Adapter_Category adapter_category = new Adapter_Category(MinhActivity.this,categoryImages);
adapter_category.notifyDataSetChanged();
gridView.setAdapter(adapter_category);
}
}
public class Adapter_Category extends BaseAdapter {
LayoutInflater inflater;
Context context;
int arr[];
public Adapter_Category( Context txt,int[] arrlist){
this.context = txt;
this.arr = arrlist;
}
public Adapter_Category(MinhActivity txt, ArrayList arrayList) {
}
@Override
public int getCount() {
return arr.length;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
我的适配器类是adapter\u Category.java
public class MinhActivity extends Activity {
GridView gridView;
int categoryImages[] ={R.drawable.android1,R.drawable.android2,R.drawable.android3,R.drawable.android4, R.drawable.android5, R.drawable.android6};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_minh);
gridView = findViewById(R.id.grView_categories);
Adapter_Category adapter_category = new Adapter_Category(MinhActivity.this,categoryImages);
adapter_category.notifyDataSetChanged();
gridView.setAdapter(adapter_category);
}
}
public class Adapter_Category extends BaseAdapter {
LayoutInflater inflater;
Context context;
int arr[];
public Adapter_Category( Context txt,int[] arrlist){
this.context = txt;
this.arr = arrlist;
}
public Adapter_Category(MinhActivity txt, ArrayList arrayList) {
}
@Override
public int getCount() {
return arr.length;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
这里可能会显示错误
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (inflater==null) {
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
if (convertView == null)
{
convertView = inflater.inflate(R.layout.single_categories,null);
}
ImageView imageView = convertView.findViewById(R.id.imageView);
imageView.setImageResource(arr[position]);
return convertView;
}
}
你可以参考这个链接
但这不是最好的方法。请将Recylerview与GridLayoutManager结合使用,以获得更好的性能。请参阅您的代码正在运行,并且我的设备上会显示一个
GridView
:
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import androidx.appcompat.app.AppCompatActivity;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
GridView gridView;
int categoryImages[] ={R.mipmap.ic_launcher_round, R.drawable.ic_launcher_foreground, R.mipmap.ic_launcher_round,
R.drawable.ic_launcher_foreground, R.mipmap.ic_launcher, R.drawable.ic_launcher_foreground};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gridView = findViewById(R.id.grView_categories);
Adapter_Category adapter_category = new Adapter_Category(MainActivity.this, categoryImages);
adapter_category.notifyDataSetChanged();
gridView.setAdapter(adapter_category);
}
适配器
:
public class Adapter_Category extends BaseAdapter {
LayoutInflater inflater;
Context context;
int arr[];
public Adapter_Category(Context txt, int[] arrlist) {
this.context = txt;
this.arr = arrlist;
}
public Adapter_Category(MainActivity txt, ArrayList arrayList) {
}
@Override
public int getCount() {
return arr.length;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
if (inflater == null) {
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
if (convertView == null)
{
convertView = inflater.inflate(R.layout.single_categories, null);
}
ImageView imageView = convertView.findViewById(R.id.imageView);
imageView.setImageResource(arr[position]);
return convertView;
}
}
.xml看起来像:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<GridView
android:id="@+id/grView_categories"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:numColumns="3"
android:gravity="center" />
</androidx.constraintlayout.widget.ConstraintLayout>
如果此代码没有帮助,请添加一些错误日志。请添加您的活动\u minh.xml。检查是否显示您的主要活动