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6.1.5 GridView詳解編輯
Android中的數據能夠通過GridView類實現表格化展現，它也屬於列表類型的控件，其繼承關係如下：java.lang.Object
↳ android.view.View
↳ android.view.ViewGroup
↳ android.widget.AdapterView<T extends android.widget.Adapter>
↳ android.widget.AbsListView
↳ android.widget.GridView
GridView控件應用案例效果如圖6-10所示。
圖6-10 GridView控件使用效果圖
程序代碼請參考代碼清單6-8：
【代碼清單6-8】 chapter6_4/src/com/work/GridView_1.java
public class GridView_1 extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.grid);
GridView g = (GridView) findViewById(R.id.myGrid);
g.setAdapter(new ImageAdapter(this));
g.setOnItemSelectedListener(new OnItemSelectedListener() {
public void onItemSelected(AdapterView<?> parent, View view,
int position, long id) {
Toast.makeText(GridView_1.this, "圖片ID：" + mThumbIds[position],
Toast.LENGTH_SHORT).show();
}
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
private Integer[] mThumbIds = { R.drawable.yellowimage,
R.drawable.redimage, R.drawable.icon, R.drawable.blueimage,
R.drawable.photo1962, R.drawable.photo189, R.drawable.photo1803,
R.drawable.photo1796, R.drawable.photo1732, R.drawable.photo1553,
R.drawable.photo1537, R.drawable.photo1503, R.drawable.photo1453,
R.drawable.photo1450, R.drawable.photo1447, R.drawable.photo1441,
R.drawable.photo1433, R.drawable.photo1432, R.drawable.photo1431,
R.drawable.photo1426, R.drawable.photo1425, R.drawable.photo1424,
R.drawable.photo1423, R.drawable.photo1422, R.drawable.photo142,
R.drawable.photo140, R.drawable.photo1220, R.drawable.photo1208,
R.drawable.photo1207, R.drawable.photo101209, };
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context c) {
mContext = c;
}
public int getCount() {
return mThumbIds.length;
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(60, 60));
imageView.setPadding(8, 8, 8,
;} else {
imageView = (ImageView) convertView;
}
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
}
}
代碼的關鍵是實現BaseAdapter適配器類——ImageAdapter，代碼如下：
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(60, 60));
imageView.setPadding(8, 8, 8,
;} else {
imageView = (ImageView) convertView;
}
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
在convertView為null的時候實例化控件，imageView.setLayoutParams(new GridView.LayoutParams(60, 60)是設置一個單元格中圖片大小是60×60像素。imageView.setPadding(8, 8, 8,
設定GridView的單元格與其中的圖片之間上、下、左、右空白。布局文件chapter6_4/res/layout/grid.xml：
<?xml version="1.0" encoding="utf-8"?>
<GridView xmlns:andro
android:
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:verticalSpacing="10dp"
android:horizontalSpacing="10dp"
android:numColumns="auto_fit"
android:columnWidth="60dp"
android:gravity="center"
/>
android:verticalSpacing="10dp"是兩行之間的邊距，android:horizontalSpacing="10dp"是兩列之間的邊距。android:numColumns="auto_fit"GridView列數設置為自動，android:columnWidth="60dp"是每列的寬度，也就是項目的寬度。android:gravity="center"是居中。
出自《Android開發案例驅動教程》第六章
最後更新：2017-04-02 06:51:43