在Android

Question

我在公共类中声明AlertBox方法并在其他类中使用它时遇到以下错误：

  

“android.view.WindowManager $ BadTokenException：无法添加窗口    - 令牌null不适用于应用程序“

private void AlertBox(String s, final String err, final Context con){ 
    AlertDialog.Builder builder1 = new AlertDialog.Builder(con).create(); 
    builder1.setMessage(s); builder1.setCancelable(true); 
    builder1.setPositiveButton( "Ok", new DialogInterface.OnClickListener() { 
        public void onClick(DialogInterface dialog, int id) {
            dialog.cancel();
        }
    }); builder1.show(); }

我查了帖子：

“Single alert dialog for entire application” 但没有一个解决方案适合我。

Answer 1

你可以试试这个

private void AlertBox(String title, final String err, final Context con){
    AlertDialog.Builder alertDialog = new AlertDialog.Builder(con);
    // Setting Dialog Title
    alertDialog.setTitle(title);
    // Setting Dialog Message
    alertDialog.setMessage(err);
    // Setting Positive "Yes" Button
    alertDialog.setPositiveButton("YES", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog,int which) {
            // Write your code here to invoke YES event
            Toast.makeText(con, "You clicked on YES", Toast.LENGTH_SHORT).show();
        }
    });

    // Setting Negative "NO" Button
    alertDialog.setNegativeButton("NO", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // Write your code here to invoke NO event
            Toast.makeText(con, "You clicked on NO", Toast.LENGTH_SHORT).show();
            dialog.cancel();
        }
    });
    // Showing Alert Message
    alertDialog.show();

     }

导入此import android.support.v7.app.AlertDialog;