Question

我的MainActivity：

import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;

 import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    ArrayList<Liste> items;
ListView listView;
ArrayAdapter arrayAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    BottomNavigationView bottomNavigationView=(BottomNavigationView) findViewById(R.id.navigation);
    bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            Fragment selectedFragment=null;
            switch (item.getItemId()){
                case R.id.item1:
                    selectedFragment=ItemOneFragment.newInstance();
                    fragment1();
                    break;
                case R.id.item2:
                    selectedFragment=ItemTwoFragment.newInstance();
                    fragment2();
                    break;
                case R.id.item3:
                    selectedFragment=ItemThreeFragment.newInstance();
                    fragment3();
                    break;
            }
            FragmentTransaction transaction=getSupportFragmentManager().beginTransaction();
            transaction.replace(R.id.frame_layout,selectedFragment);
            transaction.commit();
            return true;
        }
    });
    FragmentTransaction transaction=getSupportFragmentManager().beginTransaction();
    transaction.replace(R.id.frame_layout,ItemOneFragment.newInstance());
    transaction.commit();
}
public void fragment1(){

}
public void fragment2(){

}
public void fragment3(){
    items=new ArrayList<>();

    items.add(new Liste("Hiiii",android.R.drawable.ic_dialog_info));
   // items.add(new Liste("Hiiii",R.drawable.));

    listView=(ListView) findViewById(R.id.listv);
    arrayAdapter=new Adapter(this,items);

   listView.setAdapter(arrayAdapter);
}
}

我的ArrayAdapter：

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.ArrayList;

class Adapter extends ArrayAdapter<Liste> {
    Adapter(Context context, ArrayList<Liste> item) {
        super(context, R.layout.fragment3,item);
    }
   @Override
    public View getView(int position,View convertView,ViewGroup parent){
        LayoutInflater inflater= LayoutInflater.from(getContext());
        View customView=inflater.inflate(R.layout.fragment3,parent,false);
        String nam= getItem(position).getName();
        int resource=getItem(position).getResource();

        TextView viewTitel= customView.findViewById(R.id.textView);
        ImageView imageView= customView.findViewById(R.id.imageView);


        viewTitel.setText(nam);
        imageView.setImageResource(resource);

        return customView;
    }
}

我的Liste：

class Liste {

private String name;
private int resource;



Liste(String name, int resource){
    this.name=name;
    this.resource=resource;
}
public String getName(){
    return name;
}
public void setName(String name){
    this.name=name;
}
public int getResource(){
    return resource;
}
public void setResource(int resource){
    this.resource=resource;
}

}

我的ListView xml与ImageView和TextView

<?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"
    android:id="@+id/linearlayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="50dp"
        android:layout_alignTop="@+id/imageView"
        android:layout_marginLeft="20dp"
        android:layout_marginStart="20dp"
        android:layout_toEndOf="@+id/imageView"
        android:layout_toRightOf="@+id/imageView"
        android:textColor="@color/bottom"
        android:textColorLink="@color/colorAccent"
        android:textSize="30sp" />

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:layout_marginLeft="27dp"
        android:layout_marginStart="27dp"
        android:layout_marginTop="24dp" />
</RelativeLayout>

</LinearLayout>

和我的Fragment ListView：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
    android:background="@android:color/holo_blue_bright"
    tools:context="de.kruemelopment.org.lustigewitze.ItemThreeFragment">

<ListView
    android:id="@+id/listv"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_alignParentEnd="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true" />
</RelativeLayout>

我运行它并在listview.setAdapter(arrayAdapter)上显示错误; 但当我删除item.add(...);它有效，我认为问题是ImageView，但我现在不知道在哪里以及为什么以及如何解决它。

所以请帮助我。

帮助

Answer 1

在适配器设置图像中包含以下代码

imageView.setImageResource(ContextCompat.getDrawable(mContext, 
resource);

或者您可以使用此代码

imageView.setImageResource(getResources().getDrawable(resource)); // Deprecated Now after API level 22

将ArrayAdapter设置为ListView不起作用

1 个答案: