showing custom dialog gives force close

Question

i want to show custom dialog with given size and given postion. first time when i click style btn it shows perfect what i want but open next time gives force close. below is error what i got in logcat:

     12-06 09:50:34.280: ERROR/AndroidRuntime(414): FATAL EXCEPTION: main
12-06 09:50:34.280: ERROR/AndroidRuntime(414): java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.view.ViewGroup.addViewInner(ViewGroup.java:1976)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.view.ViewGroup.addView(ViewGroup.java:1871)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.view.ViewGroup.addView(ViewGroup.java:1851)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at com.android.internal.app.AlertController.setupView(AlertController.java:365)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at com.android.internal.app.AlertController.installContent(AlertController.java:206)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.app.AlertDialog.onCreate(AlertDialog.java:251)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.app.Dialog.dispatchOnCreate(Dialog.java:307)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.app.Dialog.show(Dialog.java:225)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at com.nga.swp.MainActivity$44.onClick(MainActivity.java:1785)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.view.View.performClick(View.java:2485)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.view.View$PerformClick.run(View.java:9080)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.os.Handler.handleCallback(Handler.java:587)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.os.Handler.dispatchMessage(Handler.java:92)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.os.Looper.loop(Looper.java:123)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at android.app.ActivityThread.main(ActivityThread.java:3683)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at java.lang.reflect.Method.invokeNative(Native Method)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at java.lang.reflect.Method.invoke(Method.java:507)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
12-06 09:50:34.280: ERROR/AndroidRuntime(414):     at dalvik.system.NativeStart.main(Native Method)

following below code snippet i am using:

style.setOnClickListener(new View.OnClickListener() {
    public void onClick(View view) {
        AlertDialog.Builder builder = new AlertDialog.Builder(
                MainActivity.this)
                .setTitle("Font")
                .setView(childViewstyle)
                .setNegativeButton("Cancel",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,
                                    int position) {
                                style.setBackgroundResource(R.drawable.btn_style_off);
                            }
                        });

        AlertDialog alertDialog = builder.create();
        alertDialog.show();

        WindowManager.LayoutParams lp = new WindowManager.LayoutParams();
        lp.copyFrom(alertDialog.getWindow().getAttributes());
        lp.width = 250;
        lp.height = 360;
        lp.x = -100;
        lp.y = -90;
        alertDialog.getWindow().setAttributes(lp);
    }
});

Answer 1

First you create ALertDialog builder in onCreate Method and AlertDialog declares globally. Later you have to call alertDialog.show(); whenever you need the dialog. No need to create an alert dialog for every button click.

Answer 2

AlertDialog alertDialog = builder.create();
alertDialog.show();

move those lines after the last line:

 alertDialog.getWindow().setAttributes(lp);