android - 如何自定义 ListView 行android

Question

我有一个姓名列表，我想根据姓名开头的字母更改行的颜色。这就是我用来显示 ListView 的内容:

ma​​in.xml

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

<ListView android:id="@+id/listview"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content" 
     />

</LinearLayout>

lisviewrows.xml

<?xml version="1.0" encoding="UTF-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
</TextView>

ma​​in.java

public class Main extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        List<String> words = populateList();
        List<String> l = removeDoubles(words);
        Collections.sort(l);

        ListView lv = (ListView)findViewById(R.id.listview);

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(), R.layout.listviewrows, l);

        lv.setAdapter(adapter);

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {

            }
        });
    }

是否有一些有用的链接或示例可以提供给我？

谢谢!!

Answer 1

为此，您需要创建自己的自定义适配器。在 getView 方法(它返回要为每个列表项显示的 View )中，将您想要的颜色应用于 TextView 的背景。customAdapters 的妙处在于你可以做任何事情，并为你的列表项显示更复杂的 View ，因为你不再局限于 TextViews，你可以将你的列表项 XML 布局更改为任何类型的 View /布局。 .

像这样:

MyAdapter.java

public class MyAdapter extends BaseAdapter{
    private LayoutInflater inflater;
    private ArrayList<String> data;

    public MyAdapter(Context context, ArrayList<String> data){
    // Caches the LayoutInflater for quicker use
    this.inflater = LayoutInflater.from(context);
    // Sets the events data
    this.data= data;
    }

    public int getCount() {
        return this.data.size();
    }

    public String getItem(int position) throws IndexOutOfBoundsException{
        return this.data.get(position);
    }

    public long getItemId(int position) throws IndexOutOfBoundsException{
        if(position < getCount() && position >= 0 ){
            return position;
        }
    }

    public int getViewTypeCount(){
        return 1;
    }

    public View getView(int position, View convertView, ViewGroup parent){
        String myText = getItem(position);           

        if(convertView == null){ // If the View is not cached
            // Inflates the Common View from XML file
            convertView = this.inflater.inflate(R.id.my_row_layout, null);
        }

        // Select your color and apply it to your textview
        int myColor;
        if(myText.substring(0, 1) == "a"){
            myColor = Color.BLACK;
        }else{
        ....
        }

        convertView.findViewById(R.id.myTextViewId).setBackground(myColor);
        // Of course you will need to set the same ID in your item list XML layout.

        return convertView;
    }
}

然后在您的 Activity 中像这样设置适配器:

public class Main extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        List<String> words = populateList();
        List<String> l = removeDoubles(words);
        Collections.sort(l);

        ListView lv = (ListView)findViewById(R.id.listview);

        MyAdapter adapter = new MyAdapter(getApplicationContext(), l);

        lv.setAdapter(adapter);

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {

            }
        });
    }