如何解码android中Base64编码的jpeg图像并在ImageView上看到它?
问题描述:
我的服务器向我的android设备发送一个编码的Base64字符串。之后,我在这个方法中解码Base64字符串来绘制它。当我将它添加到Itemizedoverlay中时,我看不到图像。如何解码android中Base64编码的jpeg图像并在ImageView上看到它?
public Drawable seticon(String input){
byte[] b = Base64.decode(input, Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(b, 0, b.length);
Drawable drawable = new BitmapDrawable(decodedByte);
drawable.setBounds(0, 0, 50, 50);
return drawable;
}
public void setphotopoint(String input){
Drawable drawable = seticon(input);
PhotoOverlay aPhotoOverlay = new PhotoOverlay(drawable, this);
OverlayItem overlayitem = new OverlayItem();
overlayitem.setMarker(drawable);
aPhotoOverlay.addOverlay(overlayitem);
overlays.add(aPhotoOverlay);
}
这是我PhotoOverlay的类
public class PhotoOverlay extends ItemizedOverlay<OverlayItem>{
private ArrayList<OverlayItem> items = new ArrayList<OverlayItem>();
Context mContext ;
public PhotoOverlay(Drawable defaultMarker, Context context) {
super(boundCenterBottom(defaultMarker));
this.mContext = context;
}
public PhotoOverlay(Drawable defaultMarker) {
super(boundCenterBottom(defaultMarker));
// TODO Auto-generated constructor stub
}
protected boolean onTap(int index) {
return true;
}
public void addOverlay(OverlayItem overlay) {
items.add(overlay);
//setLastFocusedIndex(-1);
populate();
}
@Override
protected OverlayItem createItem(int i) {
// TODO Auto-generated method stub
return items.get(i);
}
public void clear() {
items.clear();
populate();
}
public void removeOverlay(OverlayItem overlay) {
items.remove(overlay);
populate();
}
@Override
public int size() {
// TODO Auto-generated method stub
return items.size();
}
}
答
将您的二进制文件为Base64,然后使用下面的代码来获取它:
public static void base64ToFile(String path, String strBase64)
throws IOException {
byte[] bytes = Base64.decode(strBase64);
byteArrayTofile(path, bytes);
}
public static void byteArrayTofile(String path, byte[] bytes)
throws IOException {
File imagefile = new File(path);
File dir = new File(imagefile.getParent());
if (!dir.exists()) {
dir.mkdirs();
}
FileOutputStream fos = new FileOutputStream(imagefile);
fos.write(bytes);
fos.close();
}
二进制文件转换为Base64:
public static String fileToBase64(String path) throws IOException {
byte[] bytes = fileToByteArray(path);
return Base64.encodeBytes(bytes);
}
public static byte[] fileToByteArray(String path) throws IOException {
File imagefile = new File(path);
byte[] data = new byte[(int) imagefile.length()];
FileInputStream fis = new FileInputStream(imagefile);
fis.read(data);
fis.close();
return data;
}
将二进制转换为Base64,这是否意味着我可以将jpeg转换为二进制>> Base64而不转换为位图?如果是这样,那太棒了! – 2013-02-12 19:00:21