Java tutorial
/*** Copyright (c) 2012 CommonsWare, LLC Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0. Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. Covered in detail in the book _The Busy Coder's Guide to Android Development_ https://commonsware.com/Android */ package com.commonsware.android.scaleclip; import android.os.Bundle; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.SeekBar; abstract public class FragmentBase extends Fragment implements SeekBar.OnSeekBarChangeListener { abstract void setImageBackground(ImageView image); private ImageView image = null; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { setRetainInstance(true); View result = inflater.inflate(R.layout.scaleclip, container, false); SeekBar bar = ((SeekBar) result.findViewById(R.id.level)); bar.setOnSeekBarChangeListener(this); image = (ImageView) result.findViewById(R.id.image); setImageBackground(image); image.setImageLevel(bar.getProgress()); return (result); } @Override public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { image.setImageLevel(progress); } @Override public void onStartTrackingTouch(SeekBar seekBar) { // no-op } @Override public void onStopTrackingTouch(SeekBar seekBar) { // no-op } }