import com.dropbox.client2.session.Session.AccessType; //导入依赖的package包/类
public boolean isLinked(Activity activity) {
		try {

		AppKeyPair appKeys = new AppKeyPair(StaticConfig.dropboxAppKey, StaticConfig.dropboxAppSecret);
		AndroidAuthSession session = new AndroidAuthSession(appKeys, AccessType.DROPBOX);
		api = new DropboxAPI<AndroidAuthSession>(session);		
//		
		KeyValueBean loginPwd = getLoginPwd(activity);
		AccessTokenPair atp = new AccessTokenPair(loginPwd.getKey(),loginPwd.getValue());
		api.getSession().setAccessTokenPair(atp);
//		return api.getSession().isLinked();
		api.metadata("/", 1, null, false, null);
		return true;
		}
		catch (DropboxException e){
			return false;
		}
		

	}
 

import com.dropbox.client2.session.Session.AccessType; //导入依赖的package包/类
@Override
public void link(Activity activity) {


		//if (isLinked(activity)) return;
		AppKeyPair appKeys = new AppKeyPair(StaticConfig.dropboxAppKey, StaticConfig.dropboxAppSecret);
		AndroidAuthSession session = new AndroidAuthSession(appKeys, AccessType.DROPBOX);
		api = new DropboxAPI<AndroidAuthSession>(session);		
		
		KeyValueBean loginPwd = getLoginPwd(activity);
		AccessTokenPair atp = new AccessTokenPair(loginPwd.getKey(),loginPwd.getValue());
		api.getSession().setAccessTokenPair(atp);
		
		 //if (!api.getSession().isLinked()) {

		api.getSession().startAuthentication(activity);
	
}
 

import com.dropbox.client2.session.Session.AccessType; //导入依赖的package包/类
/**
 * Use this method to set the access type. This must be
 * set before using Login()
 * 
 * @param type
 */
public void AccessType(AccessType type) {
	this.access_type = type;
}