Android—自定义控件实现ListView下拉刷新，androidlistview

Android—自定义控件实现ListView下拉刷新，androidlistview

这篇博客为大家介绍一个android常见的功能——ListView下拉刷新（参考自他人博客，网址忘记了，阅读他的代码自己理解注释的，希望能帮助到大家）：

首先下拉未松手时候手机显示这样的界面：

下面的代码是自定的扎样的控件：

package com.dhsr.smartID.view;

import android.content.Context;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;

import com.example.sirelinkscanapp.R;

/**
 * 自定义控件，完成下拉时候ListView显示“图标及提示正在刷新……”的布局
 * 
 * @author cyf
 * 
 */
public class XListViewHeader extends LinearLayout {
	private LinearLayout mContainer;
	// 图片
	private ImageView mArrowImageView;
	// 圆形进度条
	private ProgressBar mProgressBar;
	private TextView mHintTextView;
	// 状态
	private int mState = STATE_NORMAL;
	// 动画
	private Animation mRotateUpAnim;
	private Animation mRotateDownAnim;
	private final int ROTATE_ANIM_DURATION = 180;
	// 正常
	public final static int STATE_NORMAL = 0;
	// 准备刷新
	public final static int STATE_READY = 1;
	// 刷新中
	public final static int STATE_REFRESHING = 2;

	public XListViewHeader(Context context) {
		super(context);
		initView(context);
	}

	/**
	 * @param context
	 * @param attrs
	 */
	public XListViewHeader(Context context, AttributeSet attrs) {
		super(context, attrs);
		initView(context);
	}

	/**
	 * “ 松开即可刷新……正在刷新……”的布局
	 * 
	 * @param context
	 */
	private void initView(Context context) {
		// 初始情况，设置下拉刷新view高度为0
		LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
				LayoutParams.MATCH_PARENT, 0);
		mContainer = (LinearLayout) LayoutInflater.from(context).inflate(
				R.layout.xlistview_header, null);
		// 加载视图
		addView(mContainer, lp);
		// 居中方式
		setGravity(Gravity.BOTTOM);
		// 初始化控件
		mArrowImageView = (ImageView) findViewById(R.id.xlistview_header_arrow);
		mHintTextView = (TextView) findViewById(R.id.xlistview_header_hint_textview);
		mProgressBar = (ProgressBar) findViewById(R.id.xlistview_header_progressbar);
		// 设置动画
		mRotateUpAnim = new RotateAnimation(0.0f, -180.0f,
				Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
				0.5f);
		mRotateUpAnim.setDuration(ROTATE_ANIM_DURATION);
		mRotateUpAnim.setFillAfter(true);
		mRotateDownAnim = new RotateAnimation(-180.0f, 0.0f,
				Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
				0.5f);
		mRotateDownAnim.setDuration(ROTATE_ANIM_DURATION);
		mRotateDownAnim.setFillAfter(true);
	}

	/**
	 * 根据下拉状态执行相应的功能，开始以及停止相应的动画
	 * 
	 * @param state
	 */
	public void setState(int state) {
		if (state == mState)
			return;
		if (state == STATE_REFRESHING) { // 显示进度
			mArrowImageView.clearAnimation();
			mArrowImageView.setVisibility(View.INVISIBLE);
			mProgressBar.setVisibility(View.VISIBLE);
		} else { // 显示箭头图片
			mArrowImageView.setVisibility(View.VISIBLE);
			mProgressBar.setVisibility(View.INVISIBLE);
		}
		switch (state) {
		
		case STATE_NORMAL:
			if (mState == STATE_READY) {
				// 开始动画
				mArrowImageView.startAnimation(mRotateDownAnim);
			}
			//刷新中
			if (mState == STATE_REFRESHING) {
				// 清除动画
				mArrowImageView.clearAnimation();
			}
			mHintTextView.setText(R.string.xlistview_header_hint_normal);
			break;
		case STATE_READY:
			if (mState != STATE_READY) {
				mArrowImageView.clearAnimation();
				mArrowImageView.startAnimation(mRotateUpAnim);
				mHintTextView.setText(R.string.xlistview_header_hint_ready);
			}
			break;
		case STATE_REFRESHING:
			mHintTextView.setText(R.string.xlistview_header_hint_loading);
			break;
		default:
		}

		mState = state;
	}
    
	public void setVisiableHeight(int height) {
		if (height < 0)
			height = 0;
		LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) mContainer
				.getLayoutParams();
		lp.height = height;
		mContainer.setLayoutParams(lp);
	}

	public int getVisiableHeight() {
		return mContainer.getHeight();
	}

}

 接下来需要自定义自己的ListView继承与android本身的ListView，方便自己添加新的方法。

package com.dhsr.smartID.view;

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewTreeObserver.OnGlobalLayoutListener;
import android.view.animation.DecelerateInterpolator;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
import android.widget.TextView;

import com.example.sirelinkscanapp.R;

/**
 * 自定义ListView
 * 
 * @author cyf
 * 
 */
public class XListView extends ListView implements OnScrollListener {

	private final String TAG = "XListView";
	private float mLastY = -1;
	private Scroller mScroller;
	// 滑动
	private OnScrollListener mScrollListener;

	// 为外界创建监听
	private IXListViewListener mListViewListener;

	// 刚才定义的自定义控件
	private XListViewHeader mHeaderView;

	private RelativeLayout mHeaderViewContent;
	private TextView mHeaderTimeView;
	private int mHeaderViewHeight; // header view's height
	private boolean mEnablePullRefresh = true;
	private boolean mPullRefreshing = false; // is refreashing.

	private boolean mEnablePullLoad;
	private boolean mPullLoading;
	private boolean mIsFooterReady = false;

	// total list items, used to detect is at the bottom of listview.
	private int mTotalItemCount;

	// for mScroller, scroll back from header or footer.
	private int mScrollBack;
	private final static int SCROLLBACK_HEADER = 0;
	private final static int SCROLLBACK_FOOTER = 1;

	private final static int SCROLL_DURATION = 400; // scroll back duration
	private final static int PULL_LOAD_MORE_DELTA = 50; // when pull up >= 50px
														// at bottom, trigger
														// load more.
	private final static float OFFSET_RADIO = 1.8f; // support iOS like pull
													// feature.

	/**
	 * @param context
	 */
	public XListView(Context context) {
		super(context);
		initWithContext(context);
	}

	public XListView(Context context, AttributeSet attrs) {
		super(context, attrs);
		initWithContext(context);
	}

	public XListView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		initWithContext(context);
	}

	/**
	 * 初始化控件
	 * 
	 * @param context
	 */
	private void initWithContext(Context context) {
		mScroller = new Scroller(context, new DecelerateInterpolator());

		super.setOnScrollListener(this);

		mHeaderView = new XListViewHeader(context);
		mHeaderViewContent = (RelativeLayout) mHeaderView
				.findViewById(R.id.xlistview_header_content);
		mHeaderTimeView = (TextView) mHeaderView
				.findViewById(R.id.xlistview_header_time);

		addHeaderView(mHeaderView, null, false);

		mHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(
				new OnGlobalLayoutListener() {
					@Override
					public void onGlobalLayout() {
						mHeaderViewHeight = mHeaderViewContent.getHeight();
						getViewTreeObserver()
								.removeGlobalOnLayoutListener(this);
					}
				});
	}

	@Override
	public void setAdapter(ListAdapter adapter) {
		// make sure XListViewFooter is the last footer view, and only add once.
		if (mIsFooterReady == false) {
			if (mEnablePullLoad) {
				mIsFooterReady = true;
				// addFooterView(mFooterView);

			}
		}