Android软件开发之ListView 详解

ListView的使用方法


ListView是Android软件开发中非常重要组件之一，基本上是个软件基本都会使用ListView ，今天我通过一个demo来教大家怎么样使用ListView组件 绘制出漂亮的列表，说道ListView就不得不说Adapter适配器，因为只有通过Adapter才可以把列表中的数据映射到ListView中。
在android的开发中最Adapter 一共可以分为
ArrayAdapter<T>,
BaseAdapter,
CursorAdapter,
HeaderViewListAdapter,
ResourceCursorAdapter,
SimpleAdapter,
SimpleCursorAdapter,
WrapperListAdapter
软件开发中最常用的有ArrayAdapter<T>, BaseAdapter, SimpleAdapter，今天用一段代码向大家诠释如何使用ListView控件。

1.简单的ListView

在List列表中如果不存在过于复杂的东西 我们可以直接去new ArrayAdapter() 来绘制列表，无须继承ArrayAdapter，重写它的方法。但是如果列表中过于复杂的话就需要使用自定义布局来实现List列表。

public class SimpleList extends ListActivity {

private String[] mListStr = { "姓名：雨松MOMO", "性别：男", "年龄：25", "居住地：北京", "邮箱：[email protected]"};

ListView mListView = null;

@Override

protected void onCreate(Bundle savedInstanceState) {

mListView = getListView();

setListAdapter( new ArrayAdapter<String>( this,

android.R.layout.simple_list_item_1, mListStr));

mListView.setOnItemClickListener( new OnItemClickListener() {

@Override

public void onItemClick(AdapterView<?> adapterView, View view, int position,

long id) {

Toast.makeText(SimpleList. this, "您选择了" + mListStr[position], Toast.LENGTH_LONG).show();

}

});



super.onCreate(savedInstanceState);

}

}

2.带标题的ListView列表

使用 simpleAdapter 需要注意的是须要用Map<String,Object> item 来保存列表中每一项的显示的title与text , new SimpleAdapter的时候将map中的数据写入 ，程序就会帮我们绘制列表了。

public class TitleList extends ListActivity {

private String[] mListTitle = { "姓名", "性别", "年龄", "居住地", "邮箱"};

private String[] mListStr = { "雨松MOMO", "男", "25", "北京",

"[email protected]" };

ListView mListView = null;

ArrayList<Map<String,Object>> mData= new ArrayList<Map<String,Object>>();;



@Override

protected void onCreate(Bundle savedInstanceState) {

mListView = getListView();



int lengh = mListTitle.length;

for( int i =0; i < lengh; i++) {

Map<String,Object> item = new HashMap<String,Object>();

item.put( "title", mListTitle[i]);

item.put( "text", mListStr[i]);

mData.add(item);    

}

SimpleAdapter adapter = new SimpleAdapter( this,mData,android.R.layout.simple_list_item_2,

new String[]{ "title", "text"}, new int[]{android.R.id.text1,android.R.id.text2});

setListAdapter(adapter);

mListView.setOnItemClickListener( new OnItemClickListener() {

@Override

public void onItemClick(AdapterView<?> adapterView, View view, int position,

long id) {

Toast.makeText(TitleList. this, "您选择了标题：" + mListTitle[position] + "内容："+mListStr[position], Toast.LENGTH_LONG).show();

}

});

super.onCreate(savedInstanceState);

}

}

 

 

3.带图片的ListView列表

使用 simpleAdapter 来操作 但是构造simpleAdapter的时候须要使用我们自己写的布局来完成 ，因为系统的布局已经不能满足需求了，同样Map<String,Object> item 来保存列表中每一项须要的显示内容 如 图片 标题 内容等。


添加我们自己的列表布局 图片 标题 内容

<?xml version= "1.0" encoding= "utf-8"?>



<RelativeLayout xmlns:android= "http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent" android:layout_height="?android:attr/listPreferredItemHeight">

<ImageView android:id="@+id/image"

android:layout_width="wrap_content" android:layout_height="fill_parent"

android:layout_alignParentTop="true" android:layout_alignParentBottom="true"

android:adjustViewBounds="true"

android:padding="2dip" />

<TextView android:id="@+id/title"

android:layout_width="wrap_content" android:layout_height="wrap_content"

android:layout_toRightOf="@+id/image"

android:layout_alignParentRight="true" android:layout_alignParentTop="true"

android:layout_above="@+id/text"

android:layout_alignWithParentIfMissing="true" android:gravity="center_vertical"

android:textSize="15dip" />

<TextView android:id="@+id/text"

android:layout_width="fill_parent" android:layout_height="wrap_content"

android:layout_toRightOf="@+id/image"

android:layout_alignParentBottom="true"

android:layout_alignParentRight="true" android:singleLine="true"

android:ellipsize="marquee"    

android:textSize="20dip" />

</RelativeLayout>

 

 

 

public class IconList extends ListActivity {

private String[] mListTitle = { "姓名", "性别", "年龄", "居住地", "邮箱"};

private String[] mListStr = { "雨松MOMO", "男", "25", "北京",

"[email protected]" };

ListView mListView = null;

ArrayList<Map<String,Object>> mData= new ArrayList<Map<String,Object>>();;



@Override

protected void onCreate(Bundle savedInstanceState) {

mListView = getListView();



int lengh = mListTitle.length;

for( int i =0; i < lengh; i++) {

Map<String,Object> item = new HashMap<String,Object>();

item.put( "image", R.drawable.jay);

item.put( "title", mListTitle[i]);

item.put( "text", mListStr[i]);

mData.add(item);    

}

SimpleAdapter adapter = new SimpleAdapter( this,mData,R.layout.iconlist,

new String[]{ "image", "title", "text"}, new int[]{R.id.image,R.id.title,R.id.text});

setListAdapter(adapter);

mListView.setOnItemClickListener( new OnItemClickListener() {

@Override

public void onItemClick(AdapterView<?> adapterView, View view, int position,

long id) {

Toast.makeText(IconList. this, "您选择了标题：" + mListTitle[position] + "内容："+mListStr[position], Toast.LENGTH_LONG).show();

}

});

super.onCreate(savedInstanceState);

}

}

4.自定义布局BaseAdapter修改列表颜色

因为通过直接 构造系统的布局来绘制列表方法肯定是有限的，所以我们需要重写绘制方法 ，写一个类去继承BaseAdapter 并实现这个类中的方法，listView在一开始绘制的时候首先会调用getCout()方法得到绘制次数 ，然后会实例化自己定义的BaseAdapter通过getView()方法一层一层绘制ListView,所以我们可以在这里面根据position(当前绘制的ID)来任意的修改绘制的内容，做出好看漂亮的ListView,下面这个例子我通过重写getView修改每个列表的颜色 并且实现用户选中后成高亮状态。

 

1. public class ColorList extends ListActivity {
   
   private String[] mListTitle = { "姓名", "性别", "年龄", "居住地", "邮箱"};
   
   private String[] mListStr = { "雨松MOMO", "男", "25", "北京",
   
   "[email protected]" };
   
   ListView mListView = null;
   
   MyListAdapter myAdapter = null;
   
   @Override
   
   protected void onCreate(Bundle savedInstanceState) {
   
   mListView = getListView();
   
   myAdapter = new MyListAdapter( this);
   
   setListAdapter(myAdapter);
   
   mListView.setOnItemClickListener( new OnItemClickListener() {
   
   @Override
   
   public void onItemClick(AdapterView<?> adapterView, View view, int position,
   
   long id) {
   
   View v=adapterView.getChildAt(position);
   
   v.setBackgroundColor(Color.RED);
   
   Toast.makeText(ColorList. this, "您选择了" + mListStr[position], Toast.LENGTH_LONG).show();
   
   }
   
   });
   
   
   
   super.onCreate(savedInstanceState);
   
   }
   
   
   
   class MyListAdapter extends BaseAdapter {
   
   private int[] colors = new int[] { 0xff626569, 0xff4f5257 };
   
   public MyListAdapter(Context context) {
   
   mContext = context;
   
   }
   
   
   
   public int getCount() {
   
   return mListStr.length;
   
   }
   
   
   
   @Override
   
   public boolean areAllItemsEnabled() {
   
   return false;
   
   }
   
   
   
   public Object getItem( int position) {
   
   return position;
   
   }
   
   
   
   public long getItemId( int position) {
   
   return position;
   
   }
   
   
   
   public View getView( int position, View convertView, ViewGroup parent) {
   
   ImageView iamge = null;
   
   TextView title = null;
   
   TextView text = null;
   
   if (convertView == null) {
   
   convertView = LayoutInflater.from(mContext).inflate(R.layout.colorlist, null);
   
   iamge = (ImageView) convertView.findViewById(R.id.color_image);
   
   title =(TextView) convertView.findViewById(R.id.color_title);
   
   text= (TextView) convertView.findViewById(R.id.color_text);
   
   }    
   
   int colorPos = position % colors.length;
   
   convertView.setBackgroundColor(colors[colorPos]);
   
   title.setText(mListTitle[position]);
   
   text.setText(mListStr[position]);
   
   iamge.setImageResource(R.drawable.jay);
   
   return convertView;
   
   }
   
   
   
   private Context mContext;
   
   }
   
   }
   

5.自定义布局ArrayAdapter
ArrayAdapter是BaseAdapter的子类，ArrayAdapter不仅具有BaseAdapter的所有方法还自定义了一些新的方法来处理列表项，所以单纯的从功能能上来讲ArrayAdapter远远强与BaseAdapter，如果是绘制一些数量比较少的列表建议使用BaseAdapter 如果绘制一些比较复杂的列表项 并且列表项很多的 建议使用ArrayAdapter。

<?xml version= "1.0" encoding= "utf-8"?>



<RelativeLayout xmlns:android= "http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent" android:layout_height="wrap_content">

<Button

android:id="@+id/array_button"

android:layout_width="wrap_content"    

android:layout_height="wrap_content"

android:text="一个按钮"

/>

<ImageView android:id="@+id/array_image"

android:layout_toRightOf="@+id/array_button"

android:layout_width="wrap_content" android:layout_height="fill_parent"

android:layout_alignParentTop="true" android:layout_alignParentBottom="true"

android:adjustViewBounds="true"

android:padding="2dip" />

<TextView android:id="@+id/array_title"

android:layout_width="fill_parent" android:layout_height="wrap_content"

android:layout_toRightOf="@+id/array_image"

android:layout_alignParentBottom="true"

android:layout_alignParentRight="true" android:singleLine="true"

android:ellipsize="marquee"    

android:textSize="15dip" />

<TextView android:id="@+id/array_text"

android:layout_width="fill_parent" android:layout_height="wrap_content"

android:layout_toRightOf="@+id/array_image"

android:layout_below="@+id/array_title"

android:layout_alignParentBottom="true"

android:layout_alignParentRight="true"    

android:singleLine="true"

android:ellipsize="marquee"    

android:textSize="20dip" />



</RelativeLayout>

 

public class ArrayList extends ListActivity {

private String[] mListTitle = { "姓名", "性别", "年龄", "居住地", "邮箱"};

private String[] mListStr = { "雨松MOMO", "男", "25", "北京",

"[email protected]" };

ListView mListView = null;

MyListAdapter myAdapter = null;

ArrayList arrayList = null;

@Override

protected void onCreate(Bundle savedInstanceState) {

arrayList = this;

mListView = getListView();

myAdapter = new MyListAdapter( this,R.layout.arraylist);

setListAdapter(myAdapter);

super.onCreate(savedInstanceState);

}



public class MyListAdapter extends ArrayAdapter<Object> {

int mTextViewResourceID = 0;

private Context mContext;

public MyListAdapter(Context context, int textViewResourceId) {

super(context, textViewResourceId);

mTextViewResourceID = textViewResourceId;

mContext = context;

}



private int[] colors = new int[] { 0xff626569, 0xff4f5257 };



public int getCount() {

return mListStr.length;

}



@Override

public boolean areAllItemsEnabled() {

return false;

}



public Object getItem( int position) {

return position;

}



public long getItemId( int position) {

return position;

}



public View getView( final int position, View convertView, ViewGroup parent) {

ImageView iamge = null;

TextView title = null;

TextView text = null;

Button button = null;

if (convertView == null) {

convertView = LayoutInflater.from(mContext).inflate(

mTextViewResourceID, null);

iamge = (ImageView) convertView.findViewById(R.id.array_image);

title = (TextView) convertView.findViewById(R.id.array_title);

text = (TextView) convertView.findViewById(R.id.array_text);

button = (Button)convertView.findViewById(R.id.array_button);

button.setOnClickListener( new OnClickListener() {



@Override

public void onClick(View arg0) {

Toast.makeText(arrayList, "您点击的第"+position + "个按钮", Toast.LENGTH_LONG).show();



}

});

}

int colorPos = position % colors.length;

convertView.setBackgroundColor(colors[colorPos]);

title.setText(mListTitle[position]);

text.setText(mListStr[position]);

if(colorPos == 0)

iamge.setImageResource(R.drawable.jay);

else

iamge.setImageResource(R.drawable.image);

return convertView;

}

}

}