在Android程序設計中GridView跟ListView都是比較常用的多控件布局,而GridView更是實現九宮圖的首選!本文就是介紹如何使用GridView實現九宮圖。GridView的用法很多,網上介紹最多的方法就是自己實現一個ImageAdapter繼承BaseAdapter,再供GridView使用,類似這種的方法本文不再重復,本文介紹的GridView用法跟之前介紹過的ListView極其類似。
我們先來看看本文代碼運行的結果:
本文需要添加/修改3個文件:main.xml、night_item.xml、JAVA源代碼。
main.xml源代碼如下,本身是個GirdView,用于裝載Item:
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<? xml version = "1.0" encoding = "utf-8" ?> < GridView xmlns:android = "http://schemas.android.com/apk/res/android" android:id = "@+id/gridview" android:layout_width = "fill_parent" android:layout_height = "fill_parent" android:numColumns = "auto_fit" android:verticalSpacing = "10dp" android:horizontalSpacing = "10dp" android:columnWidth = "90dp" android:stretchMode = "columnWidth" android:gravity = "center" /> |
這里簡單介紹一下里面的某些屬性:
android:numColumns="auto_fit" ,GridView的列數設置為自動
android:columnWidth="90dp",每列的寬度,也就是Item的寬度
android:stretchMode="columnWidth",縮放與列寬大小同步
android:verticalSpacing="10dp",兩行之間的邊距,如:行一(NO.0~NO.2)與行二(NO.3~NO.5)間距為10dp
android:horizontalSpacing="10dp",兩列之間的邊距。
接下來介紹 night_item.xml,這個XML跟前面ListView的ImageItem.xml很類似:
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<? xml version = "1.0" encoding = "utf-8" ?> < RelativeLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:layout_height = "wrap_content" android:paddingBottom = "4dip" android:layout_width = "fill_parent" > < ImageView android:layout_height = "wrap_content" android:id = "@+id/ItemImage" android:layout_width = "wrap_content" android:layout_centerHorizontal = "true" > </ ImageView > < TextView android:layout_width = "wrap_content" android:layout_below = "@+id/ItemImage" android:layout_height = "wrap_content" android:text = "TextView01" android:layout_centerHorizontal = "true" android:id = "@+id/ItemText" > </ TextView > </ RelativeLayout > |
最后就是JAVA的源代碼了,也跟前面的ListView的JAVA源代碼很類似,不過多了“選中”的事件處理:
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public void onCreate(Bundle savedInstanceState) { super .onCreate(savedInstanceState); setContentView(R.layout.main); GridView gridview = (GridView) findViewById(R.id.gridview); //生成動態數組,并且轉入數據 ArrayList<HashMap<String, Object>> lstImageItem = new ArrayList<HashMap<String, Object>>(); for ( int i= 0 ;i< 10 ;i++) { HashMap<String, Object> map = new HashMap<String, Object>(); map.put( "ItemImage" , R.drawable.icon); //添加圖像資源的ID map.put( "ItemText" , "NO." +String.valueOf(i)); //按序號做ItemText lstImageItem.add(map); } //生成適配器的ImageItem <====> 動態數組的元素,兩者一一對應 SimpleAdapter saImageItems = new SimpleAdapter( this , //沒什么解釋 lstImageItem, //數據來源 R.layout.night_item, //night_item的XML實現 //動態數組與ImageItem對應的子項 new String[] { "ItemImage" , "ItemText" }, //ImageItem的XML文件里面的一個ImageView,兩個TextView ID new int [] {R.id.ItemImage,R.id.ItemText}); //添加并且顯示 gridview.setAdapter(saImageItems); //添加消息處理 gridview.setOnItemClickListener( new ItemClickListener()); } //當AdapterView被單擊(觸摸屏或者鍵盤),則返回的Item單擊事件 class ItemClickListener implements OnItemClickListener { public void onItemClick(AdapterView<?> arg0, //The AdapterView where the click happened View arg1, //The view within the AdapterView that was clicked int arg2, //The position of the view in the adapter long arg3 //The row id of the item that was clicked ) { //在本例中arg2=arg3 HashMap<String, Object> item=(HashMap<String, Object>) arg0.getItemAtPosition(arg2); //顯示所選Item的ItemText setTitle((String)item.get( "ItemText" )); } } |