Showing a Custom Loader in Android

CustomProgressDialogAndroid.java

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TransparentProgressDialog.java

public class TransparentProgressDialog extends Dialog {

    private ImageView iv;

    public TransparentProgressDialog(Context context, int resourceIdOfImage) {
        super(context, R.style.TransparentProgressDialog);
        WindowManager.LayoutParams wlmp = getWindow().getAttributes();
        wlmp.gravity = Gravity.CENTER_HORIZONTAL;
        getWindow().setAttributes(wlmp);
        setTitle(null);
        setCancelable(false);
        setOnCancelListener(null);
        LinearLayout layout = new LinearLayout(context);
        layout.setOrientation(LinearLayout.VERTICAL);
        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(75, 75);
        iv = new ImageView(context);
        iv.setImageResource(resourceIdOfImage);
        layout.addView(iv, params);
        addContentView(layout, params);
    }

    @Override
    public void show() {
        super.show();
        RotateAnimation anim = new RotateAnimation(0.0f, 360.0f , Animation.RELATIVE_TO_SELF, .5f, Animation.RELATIVE_TO_SELF, .5f);
        anim.setInterpolator(new LinearInterpolator());
        anim.setRepeatCount(Animation.INFINITE);
        anim.setDuration(3000);
        iv.setAnimation(anim);
        iv.startAnimation(anim);
    }
}
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styles.xml

    <!--  Transparent dialog -->
    <style name="TransparentProgressDialog" parent="android:style/Theme.Dialog">
        <item name="android:windowFrame">@null</item>
        <item name="android:windowBackground">@android:color/transparent</item>
        <item name="android:windowIsFloating">true</item>
        <item name="android:windowContentOverlay">@null</item>
        <item name="android:windowTitleStyle">@null</item>
        <item name="android:windowAnimationStyle">@android:style/Animation.Dialog</item>
        <item name="android:windowSoftInputMode">stateUnspecified|adjustPan</item>
        <item name="android:backgroundDimEnabled">true</item>
        <item name="android:background">@android:color/transparent</item>
    </style>
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private class LongOperation extends AsyncTask<String, Void, String> {

TransparentProgressDialog pd;

        @Override
        protected String doInBackground(String... params) {
          
            return "Executed";
        }

        @Override
        protected void onPostExecute(String result) {

            if (pd.isShowing())
                pd.dismiss();

        }

        @Override
        protected void onPreExecute() {
             pd = new TransparentProgressDialog(getActivity(), R.drawable.loader);
        }

        @Override
        protected void onProgressUpdate(Void... values) {}
    }