android listview 的弹性滑动 简单demo 实现

来源:互联网 发布:锐捷网络 上海华讯 编辑:程序博客网 时间:2024/06/05 09:15

弹性滑动的效果比较好看。但是 在2.2以下版本中,android 本身没有实现,想要实现这中效果要自己去写

前几天在iteye上看见了一个博客给我很大的启示,于是自己动手实验了一下感觉还可以。在这里把我的源码给大家贴上让大家一起分享,希望大家也能提出更好的意见。废话不多说上源码:

1.自己些一个MyListview  继承listview 类:

  1. package com.wljie;
  2. import android.content.Context;
  3. import android.graphics.Rect;
  4. import android.util.AttributeSet;
  5. import android.util.Log;
  6. import android.view.GestureDetector;
  7. import android.view.MotionEvent;
  8. import android.view.View;
  9. import android.view.GestureDetector.OnGestureListener;
  10. import android.view.animation.TranslateAnimation;
  11. import android.widget.ListView;
  12. public class MyListView extends ListView {
  13. private Context context;
  14. private boolean outBound = false;
  15. private int distance;
  16. private int firstOut;
  17. private static final String TAG = "wljie";
  18. public MyListView(Context context, AttributeSet attrs) {
  19. super(context, attrs);
  20. this.context = context;
  21. Log.d(TAG, "IN 1");
  22. }
  23. public MyListView(Context context, AttributeSet attrs, int defStyle) {
  24. super(context, attrs, defStyle);
  25. this.context = context;
  26. Log.d(TAG, "IN 2");
  27. }
  28. public MyListView(Context context) {
  29. super(context);
  30. this.context = context;
  31. Log.d(TAG, "IN 3");
  32. }
  33. GestureDetector gestureDetector = new GestureDetector(
  34. new OnGestureListener() {
  35. @Override
  36. public boolean onSingleTapUp(MotionEvent e) {
  37. // TODO Auto-generated method stub
  38. return false;
  39. }
  40. @Override
  41. public void onShowPress(MotionEvent e) {
  42. // TODO Auto-generated method stub
  43. }
  44. /**
  45. * 手势滑动的时候触发
  46. */
  47. @Override
  48. public boolean onScroll(MotionEvent e1, MotionEvent e2,
  49. float distanceX, float distanceY) {
  50. Log.d(TAG, "ENTER onscroll");
  51. int firstPos = getFirstVisiblePosition();
  52. int lastPos = getLastVisiblePosition();
  53. int itemCount = getCount();
  54. // outbound Top
  55. if (outBound && firstPos != 0 && lastPos != (itemCount - 1)) {
  56. scrollTo(0, 0);
  57. return false;
  58. }
  59. View firstView = getChildAt(firstPos);
  60. if (!outBound)
  61. firstOut = (int) e2.getRawY();
  62. if (firstView != null
  63. && (outBound || (firstPos == 0
  64. && firstView.getTop() == 0 && distanceY < 0))) {
  65. // Record the length of each slide
  66. distance = firstOut - (int) e2.getRawY();
  67. scrollTo(0, distance / 2);
  68. return true;
  69. }
  70. // outbound Bottom
  71. return false;
  72. }
  73. @Override
  74. public void onLongPress(MotionEvent e) {
  75. // TODO Auto-generated method stub
  76. }
  77. @Override
  78. public boolean onFling(MotionEvent e1, MotionEvent e2,
  79. float velocityX, float velocityY) {
  80. // TODO Auto-generated method stub
  81. return false;
  82. }
  83. @Override
  84. public boolean onDown(MotionEvent e) {
  85. // TODO Auto-generated method stub
  86. return false;
  87. }
  88. });
  89. @Override
  90. public boolean dispatchTouchEvent(MotionEvent event) {
  91. Log.d(TAG, "dispatchTouchEvent");
  92. int act = event.getAction();
  93. if ((act == MotionEvent.ACTION_UP || act == MotionEvent.ACTION_CANCEL)
  94. && outBound) {
  95. outBound = false;
  96. // scroll back
  97. }
  98. if (!gestureDetector.onTouchEvent(event)) {
  99. outBound = false;
  100. } else {
  101. outBound = true;
  102. }
  103. Rect rect = new Rect();  
  104.         getLocalVisibleRect(rect);  
  105.         TranslateAnimation am = new TranslateAnimation( 0, 0, -rect.top, 0);  
  106.         am.setDuration(300);  
  107.         startAnimation(am);  
  108.         scrollTo(0, 0);
  109. return super.dispatchTouchEvent(event);
  110. }
  111. }

复制代码
2.在main.xml 中写入
  1. <?xml version="1.0" encoding="utf-8"?>
  2. <LinearLayout   
  3.         android:id="@+id/LinearLayout01"   
  4.         android:layout_width="fill_parent"   
  5.         android:layout_height="fill_parent"   
  6.         xmlns:android="http://schemas.android.com/apk/res/android"
  7.         >  
  8.         <com.wljie.MyListView
  9.         android:layout_width="wrap_content"   
  10.                   android:layout_height="wrap_content"   
  11.                   android:id="@+id/MyListView"/>  
  12. </LinearLayout>
复制代码
3.创建一个my_listitem.xml
  1. <?xml version="1.0" encoding="utf-8"?>
  2. <LinearLayout   
  3.         android:layout_width="fill_parent"   
  4.         xmlns:android="http://schemas.android.com/apk/res/android"   
  5.         android:orientation="vertical"  
  6.         android:layout_height="wrap_content"   
  7.         android:id="@+id/MyListItem"   
  8.         android:paddingBottom="3dip"   
  9.         android:paddingLeft="10dip">  
  10.         <TextView   
  11.                 android:layout_height="wrap_content"   
  12.                 android:layout_width="fill_parent"   
  13.                 android:id="@+id/ItemTitle"   
  14.                 android:textSize="30dip">  
  15.         </TextView>  
  16.         <TextView   
  17.                 android:layout_height="wrap_content"   
  18.                 android:layout_width="fill_parent"   
  19.                 android:id="@+id/ItemText">  
  20.         </TextView>
  21. </LinearLayout>
复制代码
4.在Main.java中进行下一步的显示
  1. package com.wljie;
  2. import java.util.ArrayList;
  3. import java.util.HashMap;
  4. import android.app.Activity;
  5. import android.graphics.Rect;
  6. import android.os.Bundle;
  7. import android.view.animation.TranslateAnimation;
  8. import android.widget.SimpleAdapter;
  9. public class Main extends Activity {
  10. /** Called when the activity is first created. */
  11. @Override
  12. public void onCreate(Bundle savedInstanceState) {
  13. super.onCreate(savedInstanceState);
  14. setContentView(R.layout.main);
  15. // 绑定XML中的ListView,作为Item的容器
  16. MyListView list = (MyListView) findViewById(R.id.MyListView);
  17. // 生成动态数组,并且转载数据
  18. ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();
  19. for (int i = 0; i < 30; i++) {
  20. HashMap<String, String> map = new HashMap<String, String>();
  21. map.put("ItemTitle", "This is Title.....");
  22. map.put("ItemText", "This is text.....");
  23. mylist.add(map);
  24. }
  25. // 生成适配器,数组===》ListItem
  26. SimpleAdapter mSchedule = new SimpleAdapter(this, // 没什么解释
  27. mylist,// 数据来源
  28. R.layout.my_listitem,// ListItem的XML实现
  29. // 动态数组与ListItem对应的子项
  30. new String[] { "ItemTitle", "ItemText" },
  31. // ListItem的XML文件里面的两个TextView ID
  32. new int[] { R.id.ItemTitle, R.id.ItemText });
  33. // 添加并且显示
  34. list.setAdapter(mSchedule);

  35. }
  36. }
复制代码
原创粉丝点击