Android 常用数据适配器ArrayAdapter

接着上篇文章《Android 采用Layout Inflater创建一个View对象》,本文采用常用数据适配器ArrayAdapter

新建项目后,在layout文件夹下新建list_item.xml文件,接着编辑布局,代码如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" />

    <TextView
        android:id="@+id/tv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>

接着在MainActivity中添加代码:

package com.wuyudong.arrayadapter;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class MainActivity extends Activity {

    private static String[] names = { "功能1", "功能2", "功能3", "功能4", "功能5" };

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

        ListView lv = (ListView) findViewById(R.id.lv);
        lv.setAdapter(new ArrayAdapter<String>(this, R.layout.list_item,
                R.id.tv, names));

    }
}

运行一下:

ArrayAdapter的构造函数较多,其中的参数的含义可以参见源代码

   /**
     * Constructor
     *
     * @param context The current context.
     * @param resource The resource ID for a layout file containing a TextView to use when
     *                 instantiating views.
     */
    public ArrayAdapter(Context context, int resource) {
        init(context, resource, 0, new ArrayList<T>());
    }

    /**
     * Constructor
     *
     * @param context The current context.
     * @param resource The resource ID for a layout file containing a layout to use when
     *                 instantiating views.
     * @param textViewResourceId The id of the TextView within the layout resource to be populated
     */
    public ArrayAdapter(Context context, int resource, int textViewResourceId) {
        init(context, resource, textViewResourceId, new ArrayList<T>());
    }

    /**
     * Constructor
     *
     * @param context The current context.
     * @param resource The resource ID for a layout file containing a TextView to use when
     *                 instantiating views.
     * @param objects The objects to represent in the ListView.
     */
    public ArrayAdapter(Context context, int resource, T[] objects) {
        init(context, resource, 0, Arrays.asList(objects));
    }

    /**
     * Constructor
     *
     * @param context The current context.
     * @param resource The resource ID for a layout file containing a layout to use when
     *                 instantiating views.
     * @param textViewResourceId The id of the TextView within the layout resource to be populated
     * @param objects The objects to represent in the ListView.
     */
    public ArrayAdapter(Context context, int resource, int textViewResourceId, T[] objects) {
        init(context, resource, textViewResourceId, Arrays.asList(objects));
    }

    /**
     * Constructor
     *
     * @param context The current context.
     * @param resource The resource ID for a layout file containing a TextView to use when
     *                 instantiating views.
     * @param objects The objects to represent in the ListView.
     */
    public ArrayAdapter(Context context, int resource, List<T> objects) {
        init(context, resource, 0, objects);
    }

    /**
     * Constructor
     *
     * @param context The current context.
     * @param resource The resource ID for a layout file containing a layout to use when
     *                 instantiating views.
     * @param textViewResourceId The id of the TextView within the layout resource to be populated
     * @param objects The objects to represent in the ListView.
     */
    public ArrayAdapter(Context context, int resource, int textViewResourceId, List<T> objects) {
        init(context, resource, textViewResourceId, objects);
    }
原文地址:https://www.cnblogs.com/wuyudong/p/5584696.html