Sliding switching of Android screen pages and extraction of parent classes_html/css_WEB-ITnose

Because the sliding effect of the page is commonly used in the entire application, all are extracted into parent classes for introduction. See the code comments

import android.app.Activity;import android.content.SharedPreferences;import android.os.Bundle;import android.view.GestureDetector;import android.view.MotionEvent;import android.view.View;import android.view.GestureDetector.SimpleOnGestureListener;import android.widget.Toast;//定义抽象方法showNext，由基类根据需要实现，其注意功能就是滑动切换，可以按123步骤学习public abstract class BaseSetupActivity extends Activity {	//1.定义一个手势识别器		private GestureDetector detector;				protected SharedPreferences sp;		@Override		protected void onCreate(Bundle savedInstanceState) {			// TODO Auto-generated method stub			super.onCreate(savedInstanceState);			sp = getSharedPreferences("config", MODE_PRIVATE);			//2.实例化这个手势识别器,GestureDetector.SimpleOnGestureListener需要单独引用			detector = new GestureDetector(this, new SimpleOnGestureListener(){				/**				 * 当我们的手指在上面滑动的时候回调				 */				@Override				public boolean onFling(MotionEvent e1, MotionEvent e2,						float velocityX, float velocityY) {										//屏蔽在X滑动很慢的情形					if(Math.abs(velocityX)<300){						Toast.makeText(getApplicationContext(), "滑动得太慢了", 0).show();						return true;					}										//屏蔽斜滑这种情况					if(Math.abs((e2.getRawY() - e1.getRawY())) > 100){						Toast.makeText(getApplicationContext(), "不能这样滑", 0).show();												return true;					}										if((e2.getRawX() - e1.getRawX())> 200 ){						//显示上一个页面：从左往右滑动						System.out.println("显示上一个页面：从左往右滑动");						showPre();						return true;											}										if((e1.getRawX()-e2.getRawX()) > 200 ){						//显示下一个页面：从右往左滑动						System.out.println("显示下一个页面：从右往左滑动");						showNext();						return true;					}										return super.onFling(e1, e2, velocityX, velocityY);				}							});		}				public abstract void showNext();		public abstract void showPre();		/**		 * 下一步的点击事件		 * @param view		 */		public void next(View view){			showNext();					}				/**		 *   上一步		 * @param view		 */		public void pre(View view){			showPre();					}					//3.使用手势识别器		@Override		public boolean onTouchEvent(MotionEvent event) {			detector.onTouchEvent(event);			return super.onTouchEvent(event);		}}