Question

我有一个弹出窗口，我想显示一个图像和两个按钮。确实出现了按钮，但是当我尝试使用它时，ImageView会抛出nullpointer异常。下面是我显示PopUpWindow的代码片段：

private void initiatePopupWindow() {
        try {
            //We need to get the instance of the LayoutInflater, use the context of this activity
            LayoutInflater inflater = (LayoutInflater) RestPageActivity.this
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            //Inflate the view from a predefined XML layout
            View layout = inflater.inflate(R.layout.popup_details,
                    (ViewGroup) findViewById(R.id.popup_element));
            // create a 300px width and 470px height PopupWindow
            System.out.println("SELECTED INDEX" + selectedIndex + "***" + IDs.size());


            System.out.println("ITEM ID:" + IDs.get(selectedIndex) + "--------------");
            ImageView iv = (ImageView) findViewById(R.id.ivItem);

            if (StaticParameters.getCompleteData().getMenusHash().containsKey(IDs.get(selectedIndex))) {
                Menu m = StaticParameters.getCompleteData().getMenusHash().get(IDs.get(selectedIndex));
                byte[] imgBytes = FileHandler.readFile2(this, "items", m.getActiveImage());
                System.out.println("///////////////77" + imgBytes.length + "//" + m.getActiveImage());
                if (imgBytes != null && iv != null) {
                    Bitmap b = BitmapFactory.decodeByteArray(imgBytes, 0, imgBytes.length);
                    iv.setImageBitmap(b);

                    Matrix mMatrix = new Matrix();
                    mMatrix.setRectToRect(new RectF(0, 0, iv.getMeasuredWidth(), iv.getMeasuredHeight()), new RectF(0, 0, 100, 100), Matrix.ScaleToFit.CENTER);
                } else
                    System.out.println("else geldi");

            } else if (StaticParameters.getCompleteData().getProductsHash().containsKey(IDs.get(selectedIndex))) {
                Product m = StaticParameters.getCompleteData().getProductsHash().get(IDs.get(selectedIndex));
                byte[] imgBytes = FileHandler.readFile2(this, "items", m.getActiveImage());
                System.out.println("///////////////77" + imgBytes.length + "//" + m.getActiveImage());
                if (imgBytes != null && iv != null) {
                    Bitmap b = BitmapFactory.decodeByteArray(imgBytes, 0, imgBytes.length);
                    iv.setImageBitmap(b);

                    Matrix mMatrix = new Matrix();
                    mMatrix.setRectToRect(new RectF(0, 0, iv.getMeasuredWidth(), iv.getMeasuredHeight()), new RectF(0, 0, 100, 100), Matrix.ScaleToFit.CENTER);
                } else
                    System.out.println("else geldi");
            }

            pw = new PopupWindow(layout, 300, 470, true);
            // display the popup in the center
            pw.showAtLocation(layout, Gravity.CENTER, 0, 0);


            //mResultText = (TextView) layout.findViewById(R.id.server_status_text);
            Button cancelButton = (Button) layout.findViewById(R.id.cancelButton);
            //makeBlack(cancelButton);
            cancelButton.setOnClickListener(cancel_button_click_listener);
            Button approveButton = (Button) layout.findViewById(R.id.completeButton);
            //makeBlack(cancelButton);
            approveButton.setOnClickListener(approve_button_click_listener);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

Answer 1

如果您的活动中已宣布属性

private ImageView iv;

你必须改变：

ImageView iv = (ImageView) findViewById(R.id.ivItem);

通过

iv = (ImageView) findViewById(R.id.ivItem); 你得到这个nullPointer异常，因为你在本地声明它是我的问题是什么

Answer 2

更改此行

<input.*?\s*?value='([^']*)

到

await (from t in Users
from c in t.Claims
where c.ClaimType == "CompanyId" && c.ClaimValue == Id
select t).Execute();

PopUpWindow上的Android Null ImageView

2 个答案: