3年以上勿进!最简单的Android自定义ListView下拉刷新与上拉加载,代码直接拿去用~
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2024-03-16 12:12:04
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声明:本文为博主原创文章,首发简书。转载请附原文链接。
https://www.jianshu.com/u/3348b92f77a4
本文主要针对开发新手,手写实现一个最简单Android自定义listview下拉刷新和上拉加载demo。
不喜可喷,欢迎大佬留言指点。
Android中高级知识进阶、面试系列专题GitHub地址:https://github.com/Timdk857/Android-Architecture-knowledge-2-
(欢迎标星白嫖)
效果图
一:编写需要在ListView中增加头加载的布局文件,与底部加载的布局文件:
头布局文件:
<?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="horizontal" >
<FrameLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dip" >
<ImageView
android:id="@+id/iv_listview_header_arrow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:src="@mipmap/common_listview_headview_red_arrow" />
<ProgressBar
android:id="@+id/pb_listview_header"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:indeterminateDrawable="@drawable/custom_progressbar"
android:visibility="invisible" />
</FrameLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:gravity="center_horizontal"
android:orientation="vertical" >
<TextView
android:id="@+id/tv_listview_header_state"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="下拉刷新"
android:textColor="#FF0000"
android:textSize="18sp" />
<TextView
android:id="@+id/tv_listview_header_last_update_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5dip"
android:text="最后刷新时间: 1990-09-09 09:09:09"
android:textColor="@android:color/darker_gray"
android:textSize="14sp" />
</LinearLayout>
</LinearLayout>
底部布局文件:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_centerInParent="true"
android:gravity="center_vertical">
<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminateDrawable="@drawable/custom_progressbar"
/>
<TextView
android:id="@+id/tv_bottom_state"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="加载更多"
android:layout_marginLeft="10dp"/>
</LinearLayout>
</RelativeLayout>
二:自定义ListView需要的接口回调给UI,告诉UI ListView执行了下拉加载/上拉加载动作
public interface ICustomUpdateListViewBack {
public void downUpdateListData();
public void upUpdateListData();
}
自定义ListView:
public class CustomUpdateListView extends ListView implements AbsListView.OnScrollListener{
private static final String TAG = CustomUpdateListView.class.getSimpleName();
/**
* 下拉刷新
*/
private static final int DOWN_UPDATE = 111;
/**
* 准备刷新
*/
private static final int PLAN_UPDATE = 112;
/**
* 正在刷新
*/
private static final int PROCESS_UPDATE = 113;
private int thisUpdateStatusValue = DOWN_UPDATE; // 默认一直是下拉刷新
public CustomUpdateListView(Context context, AttributeSet attrs) {
super(context, attrs);
setOnScrollListener(this);
initHeader();
initBottom();
}
/**
* 定义头部相关
*/
private View headerView;
private int headerViewHeight;
private ImageView ivHeaderArrow;
private ProgressBar pbHeader;
private TextView tvHeaderState;
private TextView tvHeaderLastUpdateTime;
/**
* 定义底部相关
*/
private View bottomView;
private int bottomViewHeight;
private TextView tvBottomState;
/**
* 初始化头部 布局View相关
*/
private void initHeader() {
// 从布局中拿到一个View
headerView = View.inflate(getContext(), R.layout.listview_header, null);
// 获取头部各个控件的值
ivHeaderArrow = headerView.findViewById(R.id.iv_listview_header_arrow);
pbHeader = headerView.findViewById(R.id.pb_listview_header);
tvHeaderState = headerView.findViewById(R.id.tv_listview_header_state);
tvHeaderLastUpdateTime = headerView.findViewById(R.id.tv_listview_header_last_update_time);
tvHeaderLastUpdateTime.setText(getThisTiem());
// getHieight(); 方法只能获取到控件显示后的高度
// int headerViewHeight = headerView.getHeight();
// 结果 headerViewHeight: 0
// View的绘制流程:测量 onLayout onDraw
// 所以先测量后,就能得到测量后的高度了
headerView.measure(0, 0); // 注意:传0系统会自动去测量View高度
// 得到测量后的高度
headerViewHeight = headerView.getMeasuredHeight();
Log.i(TAG, "headerViewHeight:" + headerViewHeight);
headerView.setPadding(0, -headerViewHeight, 0 ,0);
addHeaderView(headerView);
initHeaderAnimation();
}
private void initBottom() {
bottomView = View.inflate(getContext(), R.layout.listview_bottom, null);
tvBottomState = bottomView.findViewById(R.id.tv_bottom_state);
// 先测量
bottomView.measure(0, 0);
// 获取高度
bottomViewHeight = bottomView.getMeasuredHeight();
bottomView.setPadding(0, -bottomViewHeight, 0, 0);
addFooterView(bottomView);
}
private RotateAnimation upRotateAnimation;
private RotateAnimation downRotateAnimation;
private void initHeaderAnimation() {
upRotateAnimation = new RotateAnimation(
0, 180,
Animation.RELATIVE_TO_SELF, 0.5f,
Animation.RELATIVE_TO_SELF, 0.5f);
upRotateAnimation.setDuration(500);
upRotateAnimation.setFillAfter(true);
downRotateAnimation = new RotateAnimation(
180, 360,
Animation.RELATIVE_TO_SELF, 0.5f,
Animation.RELATIVE_TO_SELF, 0.5f);
downRotateAnimation.setDuration(500);
downRotateAnimation.setFillAfter(true);
}
/**
* 滑动的状态改变
* @param view
* @param scrollState 有三种状态
* SCROLL_STATE_IDLE 代表 滑动停止状态类似于手指松开UP
* SCROLL_STATE_TOUCH_SCROLL 代表滑动触摸状态
* SCROLL_STATE_FLING 快速滑动 猛的一滑
*/
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
// 如果是猛地滑动 或者 手指松开UP 才显示底部布局View
if (scrollState == SCROLL_STATE_IDLE || scrollState == SCROLL_STATE_FLING) {
// 判断必须是底部的Item的时候
if (getLastVisiblePosition() == (getCount() -1)) {
bottomView.setPadding(0, 0, 0, 0);
// 回调接口方法
if (null != customUpdateListViewBack) {
customUpdateListViewBack.upUpdateListData();
}
}
}
}
private int firstVisibleItem;
/**
* ListView滑动的监听方法
* @param view 当前ListView
* @param firstVisibleItem 当前屏幕的第一个显示的Item
* @param visibleItemCount 当前屏幕显示的Item数量
* @param totalItemCount 总共Item数量
*/
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
this.firstVisibleItem = firstVisibleItem;
}
private int downY;
@Override
public boolean onTouchEvent(MotionEvent ev) {
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
downY = (int) ev.getY();
break;
case MotionEvent.ACTION_UP:
if (thisUpdateStatusValue == DOWN_UPDATE) {
headerView.setPadding(0, -headerViewHeight ,0 ,0);
} else {
headerView.setPadding(0, 0, 0, 0);
thisUpdateStatusValue = PROCESS_UPDATE;
updateHeaderState();
}
break;
case MotionEvent.ACTION_MOVE:
int cha = (int) ev.getY() - downY;
if (this.firstVisibleItem == 0 && cha > 0) {
int paddingTop = -headerViewHeight + cha;
// Log.i(TAG, "paddingTop:" + paddingTop);
if (thisUpdateStatusValue == PROCESS_UPDATE) {
break;
}
if (paddingTop > 0 && thisUpdateStatusValue == DOWN_UPDATE) {
// 准备刷新
Log.i(TAG, "paddingTop:" + paddingTop + ">>>准备刷新");
thisUpdateStatusValue = PLAN_UPDATE;
updateHeaderState();
} else if (paddingTop < 0 && thisUpdateStatusValue == PLAN_UPDATE) {
// 正在刷新
Log.i(TAG, "paddingTop:" + paddingTop + ">>>正在刷新");
thisUpdateStatusValue = DOWN_UPDATE;
updateHeaderState();
}
headerView.setPadding(0, paddingTop, 0, 0);
}
break;
default:
break;
}
return super.onTouchEvent(ev); // 不返回ture 而是去调用父类的方法,是保证ListView自身的滑动功能正常
}
private void updateHeaderState() {
switch (thisUpdateStatusValue) {
case DOWN_UPDATE:
ivHeaderArrow.startAnimation(downRotateAnimation);
tvHeaderState.setText("下拉刷新");
break;
case PLAN_UPDATE:
ivHeaderArrow.startAnimation(upRotateAnimation);
tvHeaderState.setText("准备刷新");
break;
case PROCESS_UPDATE:
ivHeaderArrow.setVisibility(INVISIBLE);
ivHeaderArrow.clearAnimation();
pbHeader.setVisibility(VISIBLE);
tvHeaderState.setText("正在刷新中...");
if (null != customUpdateListViewBack) {
customUpdateListViewBack.downUpdateListData();
}
break;
default:
break;
}
}
private ICustomUpdateListViewBack customUpdateListViewBack;
public void setCallback(ICustomUpdateListViewBack back) {
this.customUpdateListViewBack = back;
}
public void updateHeaderResult() {
headerView.setPadding(0, -headerViewHeight, 0, 0);
// 状态还原
ivHeaderArrow.clearAnimation();
tvHeaderState.setText("下拉刷新");
ivHeaderArrow.setVisibility(VISIBLE);
pbHeader.setVisibility(INVISIBLE);
tvHeaderLastUpdateTime.setText(getThisTiem());
thisUpdateStatusValue = DOWN_UPDATE;
}
private String getThisTiem() {
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");// HH:mm:ss
// 获取当前时间
Date date = new Date(System.currentTimeMillis());
return simpleDateFormat.format(date);
}
public void updateBottomResult() {
/*tvBottomState.setText("加载成功");
tvBottomState.setTextColor(Color.GREEN);*/
new android.os.Handler().postDelayed(new Runnable() {
@Override
public void run() {
bottomView.setPadding(0, -bottomViewHeight, 0, 0);
}
}, 2000);
}
}
三:把ProgressBar的风格修改,从白色演变成红色的形式
custom_progressbar.xml 文件:
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:fromDegrees="0"
android:pivotX="50%"
android:pivotY="50%"
android:toDegrees="360" >
<shape
android:innerRadiusRatio="3"
android:shape="ring"
android:thicknessRatio="10"
android:useLevel="false" >
<gradient
android:centerColor="#FF6A6A"
android:endColor="#FF0000"
android:startColor="#FFFFFF"
android:type="sweep" />
</shape>
</rotate>
四:如何使用自定义的ListView:
<heima.custom.CustomUpdateListView
android:id="@+id/custom_listview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@id/ll">
</heima.custom.CustomUpdateListView>
当把数据查询出来后,执行:
listView.updateHeaderResult(); // 更新头部布局复原
listView.updateBottomResult(); // 更新底部布局复原
listView.setCallback(new ICustomUpdateListViewBack() {
@Override
public void downUpdateListData() {
new AsyncTask<Void, Void, Void>() {
@Override
protected Void doInBackground(Void... voids) {
SystemClock.sleep(3000);
mData.add(0, "1最新加载出来的数据");
mData.add(1, "2最新加载出来的数据");
mData.add(2, "3最新加载出来的数据");
mData.add(3, "4最新加载出来的数据");
mData.add(4, "5最新加载出来的数据");
mData.add(5, "6最新加载出来的数据");
return null;
}
@Override
protected void onPostExecute(Void aVoid) {
// super.onPostExecute(aVoid);
adapter.notifyDataSetChanged();
listView.updateHeaderResult();
}
}.execute(new Void[]{});
}
@Override
public void upUpdateListData() {
new AsyncTask<Void, Void, Void>() {
@Override
protected Void doInBackground(Void... voids) {
SystemClock.sleep(6000);
mData.add("1commonlibrary");
mData.add("2commonlibrary");
mData.add("3commonlibrary");
mData.add("4commonlibrary");
mData.add("5commonlibrary");
mData.add("6commonlibrary");
return null;
}
@Override
protected void onPostExecute(Void aVoid) {
// super.onPostExecute(aVoid);
adapter.notifyDataSetChanged();
listView.updateBottomResult();
}
}.execute(new Void[]{});
}
};
这样,一个简单的自定义ListView下拉刷新和上拉加载就实现完成了。
Android中高级知识进阶、面试系列专题GitHub地址:https://github.com/Timdk857/Android-Architecture-knowledge-2-
(欢迎标星白嫖)
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