PopupWindowHelper是一個根據View的位置顯示PopupWindow的一個工具類、彈出PopupWindow的位置會根據指定的View出現的位置而動態改變、本Demo是用Android Studio開發的、分為兩個Module、但我個人更習慣合到一起、所以看個人需要了、程式碼很簡單、就一個PopupWindowHelper工具類、然後直接可以在Activity上面使用了、效果如下：

PopupWindowHelper程式碼

public class PopupWindowHelper {

    private View popupView;
    private
 
 PopupWindow mPopupWindow;
    private static final int TYPE_WRAP_CONTENT = 0, TYPE_MATCH_PARENT = 1;

    public PopupWindowHelper(View view) {
        popupView = view;
    }

    public void showAsDropDown(View anchor) {
        mPopupWindow.showAsDropDown(anchor);
    }

    public void showAsDropDown
 
(View anchor, int xoff, int yoff) {
        initPopupWindow(TYPE_WRAP_CONTENT);
        mPopupWindow.showAsDropDown(anchor, xoff, yoff);
    }

    public void showAtLocation(View parent, int gravity, int x, int y) {
        initPopupWindow(TYPE_WRAP_CONTENT);
        mPopupWindow.showAtLocation(parent, gravity, x, y);
    }

    public
 
 void dismiss() {
        if (mPopupWindow.isShowing()){
            mPopupWindow.dismiss();
        }
    }

    public void showAsPopUp(View anchor) {
        showAsPopUp(anchor, 0, 0);
    }

    public void showAsPopUp(View anchor, int xoff, int yoff) {
        initPopupWindow(TYPE_WRAP_CONTENT);
        mPopupWindow.setAnimationStyle(R.style.AnimationUpPopup);
        popupView.measure(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        int height = popupView.getMeasuredHeight();
        int[] location = new int[2];
        anchor.getLocationInWindow(location);
        mPopupWindow.showAtLocation(anchor, Gravity.LEFT | Gravity.TOP, location[0]   xoff, location[1] - height   yoff);
    }

    public void showFromBottom(View anchor) {
        initPopupWindow(TYPE_MATCH_PARENT);
        mPopupWindow.setAnimationStyle(R.style.AnimationFromButtom);
        mPopupWindow.showAtLocation(anchor, Gravity.LEFT | Gravity.BOTTOM, 0, 0);
    }

    public void showFromTop(View anchor) {
        initPopupWindow(TYPE_MATCH_PARENT);
        mPopupWindow.setAnimationStyle(R.style.AnimationFromTop);
        mPopupWindow.showAtLocation(anchor, Gravity.LEFT | Gravity.TOP, 0, getStatusBarHeight());
    }

    /**
     * touch outside dismiss the popupwindow, default is ture
     * @param isCancelable
     */
    public void setCancelable(boolean isCancelable) {
        if (isCancelable) {
            mPopupWindow.setOutsideTouchable(true);
            mPopupWindow.setFocusable(true);
        }else {
            mPopupWindow.setOutsideTouchable(false);
            mPopupWindow.setFocusable(false);
        }
    }

    public void initPopupWindow(int type) {
        if (type == TYPE_WRAP_CONTENT) {
            mPopupWindow = new PopupWindow(popupView, ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        }else if (type == TYPE_MATCH_PARENT) {
            mPopupWindow = new PopupWindow(popupView, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        }
        mPopupWindow.setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
        setCancelable(true);
    }

    private int getStatusBarHeight() {
        return Math.round(25 * Resources.getSystem().getDisplayMetrics().density);
    }
}

呼叫：

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private PopupWindowHelper popupWindowHelper;
    private View popView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        findViewById(R.id.button).setOnClickListener(this);
        popView = LayoutInflater.from(this).inflate(R.layout.popupview, null);
        popupWindowHelper = new PopupWindowHelper(popView);
        popView.findViewById(R.id.button3).setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.button:
                popupWindowHelper.showAsPopUp(v);
                break;
            default:
                break;
        }
    }
}