我对此略显陌生。我正在尝试实现Staggered Gridview，并将其与我的适配器一起使用会导致活动不显示任何内容。这是我的代码：
public class ImageAdapter extends BaseAdapter {
private Context mContext;
ArrayList<String> itemList = new ArrayList<String>();
public ImageAdapter(Context c) {
mContext = c;
}
void add(String path) {
itemList.add(path);
}
@Override
public int getCount() {
return itemList.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return itemList.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return 0;
}
@SuppressLint("NewApi")
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
// ImageView imageView;
SQLite db = new SQLite(mContext);
View grid;
LayoutInflater layoutInflater = getLayoutInflater();
int int_id = 0;
String cat_id = db.getCategoryID(allWishCategory.get(position));
try {
int_id = Integer.parseInt(cat_id);
} catch (NumberFormatException nfe) {
}
List<String> cat_headings = db.getAllItemsMainHeadingsWish();
if (convertView == null) {
grid = new View(mContext);
grid = layoutInflater.inflate(R.layout.category_grid_item, null);
} else {
grid = (View) convertView;
}
TextView text_cat_heading = (TextView) grid.findViewById(R.id.txtCategoryName);
Bitmap bm = null;
ImageView imageView = (ImageView) grid.findViewById(R.id.category_main_pic);
try {
// Log.d("heading name", ""+cat_headings.get(int_id));
text_cat_heading.setText(cat_headings.get(position));
if (itemList.get(position).toString().trim().contains("DCIM")) {
bm = decodeSampledBitmapFromUri(itemList.get(position), 220, 220);
} else if (itemList.get(position).toString().trim().contains("external")) {
Uri myUri = Uri.parse(itemList.get(position));
String[] proj = { MediaStore.Images.Media.DATA };
Cursor cursor = managedQuery(myUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
bm = decodeSampledBitmapFromUri(cursor.getString(column_index), 220, 220);
} else {
bm = BitmapFactory.decodeResource(getResources(), R.drawable.no_image1);
}
} catch (NullPointerException e) {
bm = BitmapFactory.decodeResource(getResources(), R.drawable.no_image1);
}
imageView.setImageBitmap(bm);
imageView.setAdjustViewBounds(true);
imageView.setMaxHeight(160);
imageView.setMaxWidth(160);
return grid;
}
private Bitmap getItemPicBitmap(String string) {
// TODO Auto-generated method stub
Bitmap bm = null;
// ImageView imageView = (ImageView)
// grid.findViewById(R.id.category_main_pic);
try {
if (string.toString().trim().contains("DCIM")) {
bm = decodeSampledBitmapFromUri(string, 220, 220);
} else if (string.toString().trim().contains("external")) {
Uri myUri = Uri.parse(string);
String[] proj = { MediaStore.Images.Media.DATA };
Cursor cursor = managedQuery(myUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
bm = decodeSampledBitmapFromUri(cursor.getString(column_index), 220, 220);
} else {
bm = BitmapFactory.decodeResource(getResources(), R.drawable.no_image1);
}
} catch (NullPointerException e) {
bm = BitmapFactory.decodeResource(getResources(), R.drawable.no_image1);
}
return bm;
}
public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {
Bitmap bm = null;
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(path, options);
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
options.inJustDecodeBounds = false;
bm = BitmapFactory.decodeFile(path, options);
return bm;
}
public int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
if (width > height) {
inSampleSize = Math.round((float) height / (float) reqHeight);
} else {
inSampleSize = Math.round((float) width / (float) reqWidth);
}
}
return inSampleSize;
}
}
ImageAdapter myImageAdapter;
public void initializeFirstAdapter() {
SQLite db = new SQLite(this);
StaggeredGridView gridview = (StaggeredGridView) findViewById(R.id.gridview_main);
myImageAdapter = new ImageAdapter(this);
gridview.setAdapter(myImageAdapter);
Log.d("myImageAdapter = ", "set");
List<String> itemOwnCat = db.getWishCategoryMainPic();
for (String cn : itemOwnCat) {
Log.d("CHECK cat_pic = ", "" + cn);
myImageAdapter.add(cn);
}
db.close();
}
主xml文件：
<?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" >
<com.origamilabs.library.views.StaggeredGridView
android:id="@+id/gridview_main"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_margin="5sp"
android:columnWidth="60sp"
android:gravity="center"
android:horizontalSpacing="10sp"
android:numColumns="2"
android:stretchMode="columnWidth"
android:verticalSpacing="10sp" />
</LinearLayout>
category_grid_item.xml文件
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#dddddd"
android:orientation="vertical"
android:padding="8sp" >
<TextView
android:id="@+id/txtCategoryName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginBottom="5sp"
android:text="Category name"
android:textAppearance="?android:attr/textAppearanceSmall" />
<ImageView
android:id="@+id/category_num_items"
android:layout_width="50sp"
android:layout_height="25sp"
android:layout_above="@+id/category_main_pic"
android:layout_marginBottom="5sp"
android:layout_toRightOf="@+id/txtCategoryName"
android:src="@drawable/numbers" />
</RelativeLayout>
这适用于普通的GridView，所以我做错了什么？
答案 0 :(得分：1)
notifyDataSetChanged之后直接致电setAdapter。
gridView.setAdapter(adapter);
adapter.notifyDataSetChanged();