Android popupwindow在指定控件正下方滑动弹出效果

用popupwindow实现在某空间正下方滑动弹出，并用SharedPreferences记录选择当前项的位置。

activity的布局文件：

popupwindow的布局文件：

动画样式需要在styles.xml中定义：

动画须在anim文件夹中定义：

弹出动画anim_pop_in.xml

隐藏动画anim_pop_out.xml

activity代码

public class PopUpWindowActivity extends Activity implements OnClickListener {
	private TextView tv_pop;
	private PopupWindow popupWindow;
	private SharedPreferences sp;
	private ImageView iv_01, iv_02, iv_03;
	private TextView tv_01, tv_02, tv_03;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.layout_popupwindow);
		sp = getSharedPreferences("state", MODE_PRIVATE);
		// 初始化时清除保存的状态数据
		Editor edit = sp.edit();
		edit.clear();
		edit.commit();

		initView();
	}

	private void initView() {
		tv_pop = (TextView) findViewById(R.id.tv_pop);
		tv_pop.setOnClickListener(this);
	}

	@Override
	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.tv_pop:
			showPopWindow(getView());
			break;

		default:
			break;
		}
	}

	private void showPopWindow(View view) {
		try {
			
			popupWindow = new PopupWindow(view, LayoutParams.MATCH_PARENT,
					LayoutParams.WRAP_CONTENT);
			popupWindow.setFocusable(true);
			popupWindow.setOutsideTouchable(true);
			ColorDrawable cd = new ColorDrawable(0x00ffffff);// 背景颜色全透明
			popupWindow.setBackgroundDrawable(cd);
			int[] location = new int[2];
			tv_pop.getLocationOnScreen(location);
			popupWindow.setAnimationStyle(R.style.style_pop_animation);// 动画效果必须放在showAsDropDown()方法上边，否则无效
			backgroundAlpha(0.5f);// 设置背景半透明
			popupWindow.showAsDropDown(tv_pop);
			//popupWindow.showAtLocation(tv_pop, Gravity.NO_GRAVITY, location[0]+tv_pop.getWidth(),location[1]);
			popupWindow.setOnDismissListener(new OnDismissListener() {

				@Override
				public void onDismiss() {
					popupWindow = null;// 当点击屏幕时，使popupWindow消失
					backgroundAlpha(1.0f);// 当点击屏幕时，使半透明效果取消
				}
			});

			if (sp.getInt("flag", 1) == 1) {
				iv_01.setVisibility(View.VISIBLE);
				tv_01.setTextColor(Color.RED);
			} else if (sp.getInt("flag", 2) == 2) {
				iv_02.setVisibility(View.VISIBLE);
				tv_02.setTextColor(Color.RED);
			} else if (sp.getInt("flag", 3) == 3) {
				iv_03.setVisibility(View.VISIBLE);
				tv_03.setTextColor(Color.RED);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	// 设置popupWindow背景半透明
	public void backgroundAlpha(float bgAlpha) {
		WindowManager.LayoutParams lp = getWindow().getAttributes();
		lp.alpha = bgAlpha;// 0.0-1.0
		getWindow().setAttributes(lp);
	}

	/*
	 * 得到popupwindow的View
	 */
	private View getView() {
		View view = LayoutInflater.from(PopUpWindowActivity.this).inflate(
				R.layout.layout_pop_item, null);
		iv_01 = (ImageView) view.findViewById(R.id.iv_01);
		iv_02 = (ImageView) view.findViewById(R.id.iv_02);
		iv_03 = (ImageView) view.findViewById(R.id.iv_03);
		tv_01 = (TextView) view.findViewById(R.id.tv_01);
		tv_02 = (TextView) view.findViewById(R.id.tv_02);
		tv_03 = (TextView) view.findViewById(R.id.tv_03);
		RelativeLayout rl_01 = (RelativeLayout) view.findViewById(R.id.rl_01);
		RelativeLayout rl_02 = (RelativeLayout) view.findViewById(R.id.rl_02);
		RelativeLayout rl_03 = (RelativeLayout) view.findViewById(R.id.rl_03);

		rl_01.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				popupWindow.dismiss();
				tv_pop.setText("名称排序");
				saveCurrentState(1);
			}
		});
		rl_02.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				popupWindow.dismiss();
				tv_pop.setText("从高到低排序");
				saveCurrentState(2);

			}
		});
		rl_03.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				iv_03.setVisibility(View.VISIBLE);
				popupWindow.dismiss();
				tv_pop.setText("从低到高排序");
				saveCurrentState(3);
			}
		});
		return view;
	}

	/*
	 * 保存当前状态 1-->名称排序 2-->从高到低 3-->从低到高
	 */
	private void saveCurrentState(int i) {
		Editor editor = sp.edit();
		editor.putInt("flag", i);
		editor.commit();
	}
}

基本就能实现了。