HorizontalScrollView 和GridView 实现横向滑动

用  HorizontalScrollView 和GridView 实现横向滑动时用几个地方需要注意的,这里记录一下,以便后续参考.

1.GridView 显示大小异常.

不管在布局中如何设置宽高,会发现都没有效果,这个时候要把HorizontalScrollView 的布局中增加 android:fillViewport="true"

2.不可以使用HorizontalScrollView直接嵌套GridView,需要有Layout包裹

然后设置Gridview的layout_width 一个具体的宽度.一个可以超出屏幕最大宽度的值,可以在布局中设置也可以在java 代码中设置.

  如果在代码中手动设置GridView 的宽度是,需要注意的是设置 setLayoutParams 的时候,参数的类型要和其parent 的layout 类型一致,比如GridView的parent 是RelativeLayout 那 GridView 的 setLayoutParams  就要是 RelativeLayout.LayoutParams 类型的.

上面说了几个需要注意的地方,下面贴上相关的代码.

HorizontalscrollActivity .java

   
public class HorizontalscrollActivity extends Activity {
	private List<HashMap<String, Object>> list ;
	private final int DATA_SIZE = 8;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_horizontal_scroll);
		
		DisplayMetrics dm = new DisplayMetrics();
		getWindowManager().getDefaultDisplay().getMetrics(dm);
		float density = dm.density;
		int ll_width = (int) ((100+5) * density * DATA_SIZE);
		RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(ll_width, RelativeLayout.LayoutParams.WRAP_CONTENT);
		GridView gv = (GridView)this.findViewById(R.id.gv);
		gv.setLayoutParams(params);
		gv.setNumColumns(DATA_SIZE);
		getData();
		ListAdapter adapter = new SimpleAdapter(this, list, R.layout.gridview_item, 
				new String[]{"itemImage","itemName"}, 
				new int[]{R.id.itemImage,R.id.itemName});
		gv.setAdapter(adapter);
	}
	private void getData() {
		list = new ArrayList<HashMap<String,Object>>();
		for (int i = 0; i < DATA_SIZE; i++) {
			HashMap<String, Object> map = new HashMap<String, Object>();
			map.put("itemImage", R.drawable.ic_launcher);
			map.put("itemName", "图片-" + i);
			list.add(map);
		}
		
	}
	
	
}

activity_horizontal_scroll.xml

   
<?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="match_parent"
    android:orientation="vertical" >
    
    <HorizontalScrollView 
        android:id="@+id/horizontalscrollview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:scrollbars="none"
        android:fillViewport="true">
        	<RelativeLayout android:id="@+id/ll_horizontalscrollview"
        	    android:layout_width="match_parent"
        		android:layout_height="wrap_content">
	           <GridView 
	        	android:id="@+id/gv"
	            android:layout_width="wrap_content"
	        	android:layout_height="match_parent"
	        	android:numColumns="auto_fit"
	        	android:horizontalSpacing="10dp"
        	/>
        	</RelativeLayout>
    </HorizontalScrollView>
</LinearLayout>

gridview_item.xml

   
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >
    <ImageView
        android:id="@+id/itemImage"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_centerHorizontal="true" >
    </ImageView>
    <TextView
        android:id="@+id/itemName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/itemImage"
        android:layout_centerHorizontal="true" >
    </TextView>
</RelativeLayout>