Android仿QQ可拉伸头部控件

本文实例为大家分享了Android仿QQ可拉伸头部控件的具体实现代码，供大家参考，具体内容如下

该控件大致思路：

1.采用继承listview加入头部view。
2.监听listview滚动。
3.自定义动画回弹。

先看效果吧：

activity-main.xml布局如下：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="horizontal"
 tools:context=".MainActivity" >

 <com.example.headerlistview.HeaderListView
 android:id="@+id/header_lv"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:cacheColorHint="@android:color/transparent"
 android:divider="@android:color/darker_gray"
 android:dividerHeight="1dip"
 android:duplicateParentState="true"
 android:scrollbars="none" >
 </com.example.headerlistview.HeaderListView>

</LinearLayout>

headerview.xml布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:orientation="vertical" >

 <ImageView 
 android:id="@+id/header_image"
 android:layout_width="match_parent"
 android:layout_height="150dip"
 android:scaleType="centerCrop"
 android:src="@drawable/lifei987"
 />

</LinearLayout>

list_item布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="80dip"
 android:gravity="center_vertical"
 android:orientation="horizontal" >
"

 <ImageView
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:src="@drawable/ic_launcher" />

 <LinearLayout
 android:layout_width="match_parent"
 android:layout_height="80dip"
 android:layout_marginLeft="10dip"
 android:orientation="vertical" >

 <TextView
 android:id="@+id/tv_name"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginTop="10dip"
 android:text="lifei" />

 <TextView
 android:id="@+id/tv_describe"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginTop="10dip"
 android:text="lifeiasdfasdfasfsadfasf" />
 </LinearLayout>

</LinearLayout>

activity代码：

package com.example.headerlistview;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.os.Bundle;
import android.app.Activity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class MainActivity extends Activity {

 private HeaderListView header_lv;

 private ImageView header_iv;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 getHeaderView();
 initView();
 }


 private void initView() {
 // TODO Auto-generated method stub
 header_lv=(HeaderListView) findViewById(R.id.header_lv);
 header_lv.addHeaderView(getHeaderView());
 header_lv.setHeaderView(header_iv);
 header_lv.setAdapter(getSimpleAdapter());
 }

 public BaseAdapter getSimpleAdapter(){
 List<Map<String, Object>> data=new ArrayList<Map<String,Object>>();
 for(int i=0;i<15;i++){
 Map<String, Object> map=new HashMap<String, Object>();
 map.put("name", "郑州___"+i);
 map.put("describe", "asdfasdfasdfasdfasdfsadfsad");
 data.add(map);
 }

 SimpleAdapter simpleAdapter=new SimpleAdapter(this, data, R.layout.list_item, new String[]{"name","describe"}, new int[]{R.id.tv_name,R.id.tv_describe});
 return simpleAdapter;
 }

 public View getHeaderView(){
 View view= getLayoutInflater().inflate(R.layout.headerview, null);
 header_iv =(ImageView) view.findViewById(R.id.header_image);
 return view;
 }

}

自定义控件HeaderListView:

package com.example.headerlistview;

import java.security.spec.ECField;

import android.annotation.SuppressLint;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.Transformation;
import android.widget.ImageView;
import android.widget.ListView;

public class HeaderListView extends ListView {

 private ImageView headerView;

 private int headerView_initHeight;//imageview初始高度

 public void setHeaderView(ImageView headerView) {
 this.headerView = headerView;
 }

 public HeaderListView(Context context) {
 super(context);
 // TODO Auto-generated constructor stub
 }

 public HeaderListView(Context context, AttributeSet attrs, int defStyle) {
 super(context, attrs, defStyle);
 // TODO Auto-generated constructor stub
 }

 public HeaderListView(Context context, AttributeSet attrs) {
 super(context, attrs);
 // TODO Auto-generated constructor stub
 }

 /**
 * listview焦点改变时--获取iamgeview高度的初始值，该值不能在构造方法中获取
 */
 @Override
 public void onWindowFocusChanged(boolean hasWindowFocus) {
 // TODO Auto-generated method stub
 super.onWindowFocusChanged(hasWindowFocus);
 if(hasWindowFocus){
 this.headerView_initHeight=headerView.getHeight();
 }
 }

 @SuppressLint("NewApi") @Override
 protected boolean overScrollBy(int deltaX, int deltaY, int scrollX,
 int scrollY, int scrollRangeX, int scrollRangeY,
 int maxOverScrollX, int maxOverScrollY, boolean isTouchEvent) {
 // 滑动过头的时候调用
 boolean bl=resizeHeaderView(deltaY);

 return bl?true:super.overScrollBy(deltaX, deltaY, scrollX, scrollY, scrollRangeX,
 scrollRangeY, maxOverScrollX, maxOverScrollY, isTouchEvent);
 }

 /**
 * 控制imageview高度的增加
 * @param deltaY 偏移量
 */
 private boolean resizeHeaderView(int deltaY) {
 if(Math.abs((double)deltaY)<200){
 if(deltaY<0){
 headerView.getLayoutParams().height=headerView.getHeight()-deltaY;
 //重新绘制
 headerView.requestLayout();
 }else{
 headerView.getLayoutParams().height=headerView.getHeight()-deltaY;
 headerView.requestLayout();
 }
 }

 return false;
 }

 @Override
 protected void onScrollChanged(int l, int t, int oldl, int oldt) {
 // TODO Auto-generated method stub
 super.onScrollChanged(l, t, oldl, oldt);
 //获取imageview父控件
 View parent=(View) headerView.getParent();
 //当父控件的top值小于零或者高度大于原始高度时触发
 if(parent.getTop()<0||headerView.getHeight()>headerView_initHeight){
 headerView.getLayoutParams().height=headerView.getHeight()+parent.getTop();
 parent.layout(parent.getLeft(),0, parent.getRight(), parent.getHeight());
 headerView.requestLayout();
 }
 }

 @Override
 public boolean onTouchEvent(MotionEvent ev) {
 // TODO Auto-generated method stub
 if(ev.getAction()==MotionEvent.ACTION_UP||ev.getAction()==MotionEvent.ACTION_CANCEL){
 MyAnimation animation=new MyAnimation(headerView, headerView_initHeight);
 animation.setDuration(200);
 headerView.startAnimation(animation);
 }
 return super.onTouchEvent(ev);
 }

 public class MyAnimation extends Animation{

 private ImageView header_iv;
 private int currentHeight;
 private int targetHeight;
 private int poorHeight;

 public MyAnimation(ImageView iv,int targetHeight){
 this.header_iv=iv;
 this.targetHeight=targetHeight;
 this.currentHeight=iv.getHeight();
 this.poorHeight=this.currentHeight-this.targetHeight;
 }

 /**
 * 动画执行期间执行该方法，不断执行
 * interpolatedTime：当前时间与duration的时间比（时间执行百分比）
 */
 @Override
 protected void applyTransformation(float interpolatedTime,
 Transformation t) {
 // TODO Auto-generated method stub
 super.applyTransformation(interpolatedTime, t);
 this.header_iv.getLayoutParams().height=(int)(currentHeight-poorHeight*interpolatedTime);
 this.header_iv.requestLayout();
 }
 }

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持自由互联。