制作一个类似QQ第三方登陆的sdk平台（安卓版）

public static boolean checkApkExist(Context context, String packageName) {
		if (packageName == null || "".equals(packageName)) {
			return false;
		}
		try {
			context.getPackageManager().getApplicationInfo(packageName,
					PackageManager.GET_UNINSTALLED_PACKAGES);
			return true;
		} catch (NameNotFoundException e) {
			return false;
		}
	}

<span style="white-space:pre">		</span>ComponentName comp = new ComponentName("com.nbg.baby", 
		"com.nbg.baby.ApiLoginActivity"); 
		
		Intent intent = new Intent();
		intent.setComponent(comp);	 
		intent.setAction(Intent.ACTION_VIEW); 
		Bundle bundle = new Bundle(); 
		bundle.putString("extra", "extra.login"); 
		intent.putExtras(bundle); 
		
		if(Utils.checkApkExist(MainActivity.this, "com.nbg.baby")){
			startActivityForResult(intent, 1);
		}else{
			Toast.makeText(MainActivity.this, "应用未安装，无法跳转", Toast.LENGTH_SHORT).show();
		}</span>

	@Override
	public void onActivityResult(int requestCode, int resultCode, Intent data) {	
		if(requestCode ==1){
			String result = data.getStringExtra("result");
			Toast.makeText(this, result, Toast.LENGTH_SHORT).show();;
		}
	}

public class YoYo {
	
	 private static YoYo sInstance;
	 private IUiListener listener;
	 
	 private YoYo(String appId, Context context)
	 {
		 
	 }
	 
	 public static synchronized YoYo createInstance(String appId, Context context)
	 {
		 if(sInstance==null){
			 sInstance= new YoYo(appId, context);
		 }
		 return sInstance;
	 }
	 
	 public void login(Activity context, IUiListener callBack)
	 {
		ComponentName comp = new ComponentName("com.nbg.baby", 
					"com.nbg.baby.ApiLoginActivity"); 
					
		Intent intent = new Intent();
		intent.setComponent(comp);	 
		intent.setAction(Intent.ACTION_VIEW); 
		Bundle bundle = new Bundle(); 
		bundle.putString("extra", "我来自星星"); 
		intent.putExtras(bundle);
		context.startActivityForResult(intent, 1);
		this.listener = callBack;
		
	 }
	 public boolean onActivityResult(int requestCode, int resultCode, Intent data) {
		 if(requestCode ==1){
				if(resultCode == Activity.RESULT_CANCELED){
					String result = data.getStringExtra("result");
					UiError e = new UiError(0, "取消登陆", "用户取消");
					this.listener.onError(e);
				}else{
					String result = data.getStringExtra("nickname");
					
					JSONObject object = new JSONObject();
					try {
						object.put("昵称", result);
						this.listener.onComplete(object);
					} catch (JSONException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
				}
			}
		 return false;
	 }
}

public interface IUiListener {
	
	  public abstract void onComplete(Object response);
	  
	 
	  public abstract void onError(UiError e);
	  
	 
	  public abstract void onCancel();
}