Android-GridView中资产文件夹中的图像
我一直致力于创建图像的网格视图,图像显示在资产文件夹中。link帮助我使用位图读取它。我目前拥有的代码是:Android-GridView中资产文件夹中的图像,android,image,android-gridview,Android,Image,Android Gridview,我一直致力于创建图像的网格视图,图像显示在资产文件夹中。link帮助我使用位图读取它。我目前拥有的代码是: public View getView(final int position, View convertView, ViewGroup parent) { try { AssetManager am = mContext.getAssets(); String list[] = am.list(""); int count_files =
public View getView(final int position, View convertView, ViewGroup parent)
{
try
{
AssetManager am = mContext.getAssets();
String list[] = am.list("");
int count_files = imagelist.length;
for(int i= 0;i<=count_files; i++)
{
BufferedInputStream buf = new BufferedInputStream(am.open(list[i]));
Bitmap bitmap = BitmapFactory.decodeStream(buf);
imageView.setImageBitmap(bitmap);
buf.close();
}
}
catch (IOException e)
{
e.printStackTrace();
}
}
非常感谢您事先提供的帮助,
Saran无需每次都阅读所有项目。只读getView方法调用中给定位置的项。此时只显示该项目
BufferedInputStream buf = new BufferedInputStream(am.open(list[position]));
Saran,下面是我用来在画廊的资产文件夹中显示图像的内容。我想gridview也是这样:
public class myActivitye extends Activity
{
private Gallery mGallery;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mGallery = (Gallery) findViewById(R.id.mygalleryinxml);
//load images into memory
mBitArray = new Bitmap[4];
try
{
//these images are stored in the root of "assets"
mBitArray[0] = getBitmapFromAsset("pic1.png");
mBitArray[1] = getBitmapFromAsset("pic2.png");
mBitArray[2] = getBitmapFromAsset("pic3.png");
mBitArray[3] = getBitmapFromAsset("pic4.png");
}
catch (IOException e)
{
e.printStackTrace();
}
mGallery.setAdapter(new GalleryAdapter(this, mBitArray));
}
public class GalleryAdapter extends BaseAdapter
{
//member variables
private Context mContext;
private Bitmap[] mImageArray;
//constructor
public GalleryAdapter(Context context, Bitmap[] imgArray)
{
mContext = context;
mImageArray = imgArray;
}
public int getCount()
{
return mImageArray.length;
}
public Object getItem(int position)
{
return position;
}
public long getItemId(int position)
{
return position;
}
//returns the individual images to the widget as it requires them
public View getView(int position, View convertView, ViewGroup parent)
{
final ImageView imgView = new ImageView(mContext);
imgView.setImageBitmap(mImageArray[position]);
//put black borders around the image
final RelativeLayout borderImg = new RelativeLayout(mContext);
borderImg.setPadding(20, 20, 20, 20);
borderImg.setBackgroundColor(0xff000000);//black
borderImg.addView(imgView);
return borderImg;
}
}//end of: class GalleryAdapter
/**
* Helper Functions
* @throws IOException
*/
private Bitmap getBitmapFromAsset(String strName) throws IOException
{
AssetManager assetManager = getAssets();
InputStream istr = assetManager.open(strName);
Bitmap bitmap = BitmapFactory.decodeStream(istr);
istr.close();
return bitmap;
}
}
您将这些图片放在
资产/
中而不是作为可绘制资源,这有什么特别的原因吗?实际上,我想动态加载这些图片,它们的数量很多。当我把它们放在资源中时,我的内存有问题。ContentProvider有点失控,所以我想我应该在资产中试用。-Saranby顺便说一句,因为您希望动态加载图像(在我的示例中,我对它们进行了硬编码),如果我是您,我会将图像放在“资产”文件夹中,然后使用am.list(“[您的文件夹名称]”);这是因为除了我自己的文件外,我还看到了资产中的Android文件getBitmapFromAsset()方法忽略了关闭它打开的InputStream。
public class myActivitye extends Activity
{
private Gallery mGallery;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mGallery = (Gallery) findViewById(R.id.mygalleryinxml);
//load images into memory
mBitArray = new Bitmap[4];
try
{
//these images are stored in the root of "assets"
mBitArray[0] = getBitmapFromAsset("pic1.png");
mBitArray[1] = getBitmapFromAsset("pic2.png");
mBitArray[2] = getBitmapFromAsset("pic3.png");
mBitArray[3] = getBitmapFromAsset("pic4.png");
}
catch (IOException e)
{
e.printStackTrace();
}
mGallery.setAdapter(new GalleryAdapter(this, mBitArray));
}
public class GalleryAdapter extends BaseAdapter
{
//member variables
private Context mContext;
private Bitmap[] mImageArray;
//constructor
public GalleryAdapter(Context context, Bitmap[] imgArray)
{
mContext = context;
mImageArray = imgArray;
}
public int getCount()
{
return mImageArray.length;
}
public Object getItem(int position)
{
return position;
}
public long getItemId(int position)
{
return position;
}
//returns the individual images to the widget as it requires them
public View getView(int position, View convertView, ViewGroup parent)
{
final ImageView imgView = new ImageView(mContext);
imgView.setImageBitmap(mImageArray[position]);
//put black borders around the image
final RelativeLayout borderImg = new RelativeLayout(mContext);
borderImg.setPadding(20, 20, 20, 20);
borderImg.setBackgroundColor(0xff000000);//black
borderImg.addView(imgView);
return borderImg;
}
}//end of: class GalleryAdapter
/**
* Helper Functions
* @throws IOException
*/
private Bitmap getBitmapFromAsset(String strName) throws IOException
{
AssetManager assetManager = getAssets();
InputStream istr = assetManager.open(strName);
Bitmap bitmap = BitmapFactory.decodeStream(istr);
istr.close();
return bitmap;
}
}