Android學習教程之下拉刷新實現代碼（11）

本文實例為大家分享了Android下拉刷新的具體代碼，供大家參考，具體內容如下

MainActivity.java代碼:

package siso.refreshablev;

import android.app.Activity;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.TextView;

import refreshableview.RefreshableView;
import refreshableview.refreshablehelper.RefreshableHelper;

public class MainActivity extends Activity implements View.OnClickListener {
 private static final String TAG = MainActivity.class.getSimpleName();

 private RefreshableView refreshableView;

 /**
 * Called when the activity is first created.
 */
 @Override
 public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);
 findViewById(R.id.main_tv).setOnClickListener(this);
 refreshableView = (RefreshableView) findViewById(R.id.main_refresh_view);
 refreshableView.setRefreshableHelper(new RefreshableHelper() {

  @Override
  public View onInitRefreshHeaderView() {
  return LayoutInflater.from(MainActivity.this).inflate(R.layout.refresh_head, null);
  }

  @Override
  public boolean onInitRefreshHeight(int originRefreshHeight) {
  refreshableView.setRefreshNormalHeight(refreshableView.getOriginRefreshHeight() / 3);
  refreshableView.setRefreshingHeight(refreshableView.getOriginRefreshHeight());
  refreshableView.setRefreshArrivedStateHeight(refreshableView.getOriginRefreshHeight());
  return false;
  }

  @Override
  public void onRefreshStateChanged(View refreshView, int refreshState) {
  TextView tv = (TextView) refreshView.findViewById(R.id.refresh_head_tv);
  switch (refreshState) {
   case RefreshableView.STATE_REFRESH_NORMAL:
   tv.setText("正常狀態");
   break;
   case RefreshableView.STATE_REFRESH_NOT_ARRIVED:
   tv.setText("往下拉可以刷新");
   break;
   case RefreshableView.STATE_REFRESH_ARRIVED:
   tv.setText("放手可以刷新");
   break;
   case RefreshableView.STATE_REFRESHING:
   tv.setText("正在刷新");
   new Thread(
    new Runnable() {
     @Override
     public void run() {
     try {
      Thread.sleep(1000l);
      runOnUiThread(new Runnable() {
      @Override
      public void run() {
       refreshableView.onCompleteRefresh();
      }
      });
     } catch (InterruptedException e) {
      Log.e(TAG, "_", e);
     }
     }
    }
   ).start();
   break;

  }
  }
 });
 }

 @Override
 public void onClick(View v) {
 switch (v.getId()) {
  case R.id.main_tv:
  Log.d(TAG, "content clicked");
  startActivity(new Intent(this, RefreshableListActivity.class));
  break;
 }
 }
}

RefreshableListActivity.java代碼:

package siso.refreshablev;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.TextView;


import java.util.ArrayList;
import java.util.List;

import refreshableview.RefreshableListView;
import refreshableview.RefreshableView;
import refreshableview.refreshablehelper.RefreshableHelper;


public class RefreshableListActivity extends Activity {
 private static final String TAG = RefreshableListActivity.class.getSimpleName();
 RefreshableListView lv;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.refreshable_list);
 lv = (RefreshableListView) findViewById(R.id.refreshable_lv);
 lv.setRefreshableHelper(new RefreshableHelper() {

  @Override
  public View onInitRefreshHeaderView() {
  return LayoutInflater.from(RefreshableListActivity.this).inflate(R.layout.refresh_head, null);
  }

  @Override
  public boolean onInitRefreshHeight(int originRefreshHeight) {
  lv.setRefreshNormalHeight(lv.getOriginRefreshHeight() / 3);
  lv.setRefreshingHeight(lv.getOriginRefreshHeight());
  lv.setRefreshArrivedStateHeight(lv.getOriginRefreshHeight());
  return false;
  }

  @Override
  public void onRefreshStateChanged(View refreshView, int refreshState) {
  TextView tv = (TextView) refreshView.findViewById(R.id.refresh_head_tv);
  switch (refreshState) {
   case RefreshableView.STATE_REFRESH_NORMAL:
   tv.setText("正常狀態");
   break;
   case RefreshableView.STATE_REFRESH_NOT_ARRIVED:
   tv.setText("往下拉可以刷新");
   break;
   case RefreshableView.STATE_REFRESH_ARRIVED:
   tv.setText("放手可以刷新");
   break;
   case RefreshableView.STATE_REFRESHING:
   tv.setText("正在刷新");
   new Thread(
    new Runnable() {
     @Override
     public void run() {
     try {
      Thread.sleep(1000l);
      runOnUiThread(new Runnable() {
      @Override
      public void run() {
       lv.onCompleteRefresh();
      }
      });
     } catch (InterruptedException e) {
      Log.e(TAG, "_", e);
     }
     }
    }
   ).start();
   break;

  }
  }
 });

 List<String> data = new ArrayList<String>();
 for (int i = 0; i < 30; i++) {
  data.add("item_" + i);
 }
 ArrayAdapter adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, data);
 lv.setAdapter(adapter);
 adapter.notifyDataSetChanged();

 }


}

NestScrollView.java代碼:

package refreshableview;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ViewParent;
import android.widget.ScrollView;


public class NestScrollView extends ScrollView {
 private static final String TAG = NestScrollView.class.getSimpleName();

 public NestScrollView(Context context) {
 super(context);
 }

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

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

 @Override
 public boolean dispatchTouchEvent(MotionEvent ev) {
 Log.d(TAG, "___[dispatchTouchEvent]ev action: " + ev.getAction());
 return super.dispatchTouchEvent(ev);
 }

 @Override
 public boolean onInterceptTouchEvent(MotionEvent ev) {
 super.onInterceptTouchEvent(ev);
 Log.d(TAG, "___[onInterceptTouchEvent]ev action: " + ev.getAction());
 if (MotionEvent.ACTION_MOVE == ev.getAction()) {
  return true;
 }
 return false;
 }

 float lastDownY;

 @Override
 public boolean onTouchEvent(MotionEvent event) {
 super.onTouchEvent(event);
 switch (event.getAction()) {
  case MotionEvent.ACTION_DOWN:
  lastDownY = event.getY();
  parentRequestDisallowInterceptTouchEvent(true); // 保證事件可往下傳遞
  Log.d(TAG, "___Down");
  return true;
//  break;
  case MotionEvent.ACTION_MOVE:
  Log.d(TAG, "___move, this.getScrollY(): " + this.getScrollY());
  boolean isTop = event.getY() - lastDownY > 0 && this.getScrollY() == 0;
  if (isTop) { // 允許父控件攔截，即不允許父控件攔截設為false
   parentRequestDisallowInterceptTouchEvent(false);
   return false;
  } else { // 不允許父控件攔截，即不允許父控件攔截設為true
   parentRequestDisallowInterceptTouchEvent(true);
   return true;
  }
//  break;
  case MotionEvent.ACTION_UP:
  Log.d(TAG, "___up, this.getScrollY(): " + this.getScrollY());
  parentRequestDisallowInterceptTouchEvent(true); // 保證事件可往下傳遞
  break;
  case MotionEvent.ACTION_CANCEL:
  Log.d(TAG, "___cancel");
  break;
 }
 return false;
 }

 /**
 * 是否允許父控件攔截事件
 * @param disallowIntercept
 */
 private void parentRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {
 ViewParent vp = getParent();
 if (null == vp) {
  return;
 }
 vp.requestDisallowInterceptTouchEvent(disallowIntercept);
 }

}

RefreshableListView.java代碼:

package refreshableview;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ValueAnimator;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.widget.ListAdapter;
import android.widget.ListView;

import refreshableview.refreshablehelper.RefreshableHelper;


public class RefreshableListView extends ListView {
 private static final String TAG = RefreshableListView.class.getSimpleName();

 public RefreshableListView(Context context) {
 super(context);
 init(context);
 }

 public RefreshableListView(Context context, AttributeSet attrs) {
 super(context, attrs);
 init(context);
 }

 public RefreshableListView(Context context, AttributeSet attrs, int defStyle) {
 super(context, attrs, defStyle);
 init(context);
 }

 /**
 * 刷新狀態
 */
 public static final int STATE_REFRESH_NORMAL = 0x21;
 public static final int STATE_REFRESH_NOT_ARRIVED = 0x22;
 public static final int STATE_REFRESH_ARRIVED = 0x23;
 public static final int STATE_REFRESHING = 0x24;
 private int refreshState;
 // 刷新狀態監聽
 private RefreshableHelper refreshableHelper;
 /**
 * 刷新的view
 */
 private View refreshHeaderView;
 /**
 * 刷新的view的真實高度
 */
 private int originRefreshHeight;
 /**
 * 有效下拉刷新需要達到的高度
 */
 private int refreshArrivedStateHeight;
 /**
 * 刷新時顯示的高度
 */
 private int refreshingHeight;
 /**
 * 正常未刷新高度
 */
 private int refreshNormalHeight;

 public void setRefreshableHelper(RefreshableHelper refreshableHelper) {
 this.refreshableHelper = refreshableHelper;
 }

 private Context context;

 private void init(Context context) {
 this.context = context;

 }

 @Override
 protected void onSizeChanged(int w, int h, int oldw, int oldh) {
 super.onSizeChanged(w, h, oldw, oldh);
 Log.d(TAG, "[onSizeChanged]w: " + w + ", h: " + h);
 Log.d(TAG, "[onSizeChanged]oldw: " + oldw + ", oldh: " + oldh);
 Log.d(TAG, "[onSizeChanged]child counts: " + this.getChildCount());

 }

 @Override
 public void setAdapter(ListAdapter adapter) {
 if (null == refreshHeaderView) {
  addHeaderView();
 }
 super.setAdapter(adapter);
 }

 private void addHeaderView() {
 if (null != refreshableHelper) {
  refreshHeaderView = refreshableHelper.onInitRefreshHeaderView();
 }
 if (null == refreshHeaderView) {
  Log.e(TAG, "refreshHeaderView is null!");
  return;
 }
 this.addHeaderView(refreshHeaderView);
 // 計算refreshHeadView尺寸
 int width = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
 int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
 refreshHeaderView.measure(width, expandSpec);

 originRefreshHeight = refreshHeaderView.getMeasuredHeight();

 boolean isUseDefault = true;
 if (null != refreshableHelper) {
  isUseDefault = refreshableHelper.onInitRefreshHeight(originRefreshHeight);
 }

 // 初始化各個高度
 if (isUseDefault) {
  refreshArrivedStateHeight = originRefreshHeight;
  refreshingHeight = originRefreshHeight;
  refreshNormalHeight = 0;
 }
 Log.d(TAG, "[onSizeChanged]refreshHeaderView origin height: " + originRefreshHeight);
 changeViewHeight(refreshHeaderView, refreshNormalHeight);

 // 初始化為正常狀態
 setRefreshState(STATE_REFRESH_NORMAL);
 }

 @Override
 public boolean dispatchTouchEvent(MotionEvent ev) {
 super.dispatchTouchEvent(ev);
// if(MotionEvent.ACTION_MOVE == ev.getAction()){
//  return true;
// }
// return false;
 return true;
 }

 private float lastDownY = Float.MAX_VALUE;

 @Override
 public boolean onTouchEvent(MotionEvent ev) {
// super.onTouchEvent(ev);
 Log.d(TAG, "[onTouchEvent]ev action: " + ev.getAction());
 switch (ev.getAction()) {
  case MotionEvent.ACTION_DOWN:
  super.onTouchEvent(ev);
  lastDownY = ev.getY();
  Log.d(TAG, "Down --> lastDownY: " + lastDownY);
  break;
  case MotionEvent.ACTION_MOVE:
  float curY = ev.getY();
  float deltaY = curY - lastDownY;
  Log.d(TAG, "Move --> deltaY(curY - downY): " + deltaY);

  int curHeight = refreshHeaderView.getMeasuredHeight();
  int exceptHeight = curHeight + (int) (deltaY / 2);

//  boolean isTop = this.getScrollY() == 0;
  boolean isTop = 0 == this.getChildAt(0).getTop();
  boolean isDropDown = curY - lastDownY > 0;
  Log.d(TAG, "isTop: " + isTop + ", getTop(): " + this.getChildAt(0).getTop());
  if (isTop) {
   if (refreshState == STATE_REFRESH_NORMAL && !isDropDown) { // 正常狀態，手指往上（列表往下滾動）
   super.onTouchEvent(ev);
   } else {
   // 如果當前沒有處在正在刷新狀態，則更新刷新狀態
   if (STATE_REFRESHING != refreshState) {
    if (curHeight >= refreshArrivedStateHeight) { // 達到可刷新狀態
    setRefreshState(STATE_REFRESH_ARRIVED);
    } else if (curHeight == refreshNormalHeight) { // 正常狀態
    setRefreshState(STATE_REFRESH_NORMAL);
    } else { // 未達到可刷新狀態
    setRefreshState(STATE_REFRESH_NOT_ARRIVED);
    }
    changeViewHeight(refreshHeaderView, Math.max(refreshNormalHeight, exceptHeight));
   } else {
    super.onTouchEvent(ev);
   }

   }

  } else {
   super.onTouchEvent(ev);
  }
  lastDownY = curY;
  break;
  case MotionEvent.ACTION_UP:
  super.onTouchEvent(ev);
  lastDownY = Float.MAX_VALUE;
  Log.d(TAG, "Up --> lastDownY: " + lastDownY);
  // 如果是達到刷新狀態，則設置正在刷新狀態的高度
  if (STATE_REFRESH_ARRIVED == refreshState) { // 達到了刷新的狀態
   startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshingHeight);
   setRefreshState(STATE_REFRESHING);
  } else if (STATE_REFRESHING == refreshState) { // 正在刷新的狀態
   startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshingHeight);
  } else {
   // 執行動畫後回歸正常狀態
   startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshNormalHeight, normalAnimatorListener);
  }
  break;
 }
 return true;
 }


 /**
 * 刷新完畢後調用此方法
 */
 public void onCompleteRefresh() {
 if (STATE_REFRESHING == refreshState) {
  setRefreshState(STATE_REFRESH_NORMAL);
  startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshNormalHeight);
 }
 }

 /**
 * 修改當前的刷新狀態
 *
 * @param expectRefreshState
 */
 private void setRefreshState(int expectRefreshState) {
 if (expectRefreshState != refreshState) {
  refreshState = expectRefreshState;
  if (null != refreshableHelper) {
  refreshableHelper.onRefreshStateChanged(refreshHeaderView, refreshState);
  }
 }
 }


 /**
 * 改變某控件的高度
 *
 * @param view
 * @param height
 */
 private void changeViewHeight(View view, int height) {
 Log.d(TAG, "[changeViewHeight]change Height: " + height);
 ViewGroup.LayoutParams lp = view.getLayoutParams();
 if (null == lp) {
  lp = new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 0);
 }
 lp.height = height;
 view.setLayoutParams(lp);
 }

 /**
 * 改變某控件的高度動畫
 *
 * @param view
 * @param fromHeight
 * @param toHeight
 */
 private void startHeightAnimation(final View view, int fromHeight, int toHeight) {
 startHeightAnimation(view, fromHeight, toHeight, null);
 }

 private void startHeightAnimation(final View view, int fromHeight, int toHeight, Animator.AnimatorListener animatorListener) {
 if (toHeight == view.getMeasuredHeight()) {
  return;
 }
 ValueAnimator heightAnimator = ValueAnimator.ofInt(fromHeight, toHeight);
 heightAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
  @Override
  public void onAnimationUpdate(ValueAnimator valueAnimator) {
  Integer value = (Integer) valueAnimator.getAnimatedValue();
  if (null == value) return;
  changeViewHeight(view, value);
  }
 });
 if (null != animatorListener) {
  heightAnimator.addListener(animatorListener);
 }
 heightAnimator.setInterpolator(new LinearInterpolator());
 heightAnimator.setDuration(300/*ms*/);
 heightAnimator.start();
 }

 AnimatorListenerAdapter normalAnimatorListener = new AnimatorListenerAdapter() {
 @Override
 public void onAnimationEnd(Animator animation) {
  super.onAnimationEnd(animation);
  setRefreshState(STATE_REFRESH_NORMAL); // 回歸正常狀態
 }
 };

 public void setRefreshArrivedStateHeight(int refreshArrivedStateHeight) {
 this.refreshArrivedStateHeight = refreshArrivedStateHeight;
 }

 public void setRefreshingHeight(int refreshingHeight) {
 this.refreshingHeight = refreshingHeight;
 }

 public void setRefreshNormalHeight(int refreshNormalHeight) {
 this.refreshNormalHeight = refreshNormalHeight;
 }

 public int getOriginRefreshHeight() {
 return originRefreshHeight;
 }

}

RefreshableView.java代碼:

package refreshableview;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ValueAnimator;
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.widget.LinearLayout;

import refreshableview.refreshablehelper.RefreshableHelper;
import siso.refreshablev.R;

public class RefreshableView extends LinearLayout {
 private static final String TAG = RefreshableView.class.getSimpleName();

 public RefreshableView(Context context) {
 super(context);
 init(context);
 }

 public RefreshableView(Context context, AttributeSet attrs) {
 super(context, attrs);

 TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.refreshableView);
 for (int i = 0, len = a.length(); i < len; i++) {
  int attrIndex = a.getIndex(i);
  switch (attrIndex) {
  case R.styleable.refreshableView_interceptAllMoveEvents:
   interceptAllMoveEvents = a.getBoolean(i, false);
   break;
  }
 }
 a.recycle();

 init(context);
 }

 public RefreshableView(Context context, AttributeSet attrs, int defStyle) {
 super(context, attrs, defStyle);
 init(context);
 }

 /**
 * 刷新狀態
 */
 public static final int STATE_REFRESH_NORMAL = 0x21;
 public static final int STATE_REFRESH_NOT_ARRIVED = 0x22;
 public static final int STATE_REFRESH_ARRIVED = 0x23;
 public static final int STATE_REFRESHING = 0x24;
 private int refreshState;
 // 刷新狀態監聽
 private RefreshableHelper refreshableHelper;

 public void setRefreshableHelper(RefreshableHelper refreshableHelper) {
 this.refreshableHelper = refreshableHelper;
 }

 private Context context;
 /**
 * 刷新的view
 */
 private View refreshHeaderView;
 /**
 * 刷新的view的真實高度
 */
 private int originRefreshHeight;
 /**
 * 有效下拉刷新需要達到的高度
 */
 private int refreshArrivedStateHeight;
 /**
 * 刷新時顯示的高度
 */
 private int refreshingHeight;
 /**
 * 正常未刷新高度
 */
 private int refreshNormalHeight;


 /**
 * 默認不允許攔截（即，往子view傳遞事件），該屬性只有在interceptAllMoveEvents為false的時候才有效
 */
 private boolean disallowIntercept = true;
 /**
 * xml中可設置它的值為false，表示不把移動的事件傳遞給子控件
 */
 private boolean interceptAllMoveEvents;

 private void init(Context context) {
 this.context = context;
 this.setOrientation(VERTICAL);

// Log.d(TAG, "[init]originRefreshHeight: " + refreshHeaderView.getMeasuredHeight());
 }

 @Override
 protected void onSizeChanged(int w, int h, int oldw, int oldh) {
 super.onSizeChanged(w, h, oldw, oldh);

 if (null != refreshableHelper) {
  refreshHeaderView = refreshableHelper.onInitRefreshHeaderView();
 }
// refreshHeaderView = LayoutInflater.from(context).inflate(R.layout.refresh_head, null);
 if (null == refreshHeaderView) {
  Log.e(TAG, "refreshHeaderView is null!");
  return;
 }
 this.removeView(refreshHeaderView);
 this.addView(refreshHeaderView, 0);

 // 計算refreshHeadView尺寸
 int width = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
 int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
 refreshHeaderView.measure(width, expandSpec);

 Log.d(TAG, "[onSizeChanged]w: " + w + ", h: " + h);
 Log.d(TAG, "[onSizeChanged]oldw: " + oldw + ", oldh: " + oldh);
 Log.d(TAG, "[onSizeChanged]child counts: " + this.getChildCount());
 originRefreshHeight = refreshHeaderView.getMeasuredHeight();

 boolean isUseDefault = true;
 if (null != refreshableHelper) {
  isUseDefault = refreshableHelper.onInitRefreshHeight(originRefreshHeight);
 }

 // 初始化各個高度
 if (isUseDefault) {
  refreshArrivedStateHeight = originRefreshHeight;
  refreshingHeight = originRefreshHeight;
  refreshNormalHeight = 0;
 }
 Log.d(TAG, "[onSizeChanged]refreshHeaderView origin height: " + originRefreshHeight);
 changeViewHeight(refreshHeaderView, refreshNormalHeight);

 // 初始化為正常狀態
 setRefreshState(STATE_REFRESH_NORMAL);

 }

 @Override
 public boolean dispatchTouchEvent(MotionEvent ev) {
 Log.d(TAG, "[dispatchTouchEvent]ev action: " + ev.getAction());
 return super.dispatchTouchEvent(ev);
 }

 @Override
 public boolean onInterceptTouchEvent(MotionEvent ev) {
 Log.d(TAG, "[onInterceptTouchEvent]ev action: " + ev.getAction());
 if (!interceptAllMoveEvents) {
  return !disallowIntercept;
 }
 // 如果設置了攔截所有move事件，即interceptAllMoveEvents為true
 if (MotionEvent.ACTION_MOVE == ev.getAction()) {
  return true;
 }
 return false;
 }

 @Override
 public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
 if (this.disallowIntercept == disallowIntercept) {
  return;
 }
 this.disallowIntercept = disallowIntercept;
 super.requestDisallowInterceptTouchEvent(disallowIntercept);
 }

 private float downY = Float.MAX_VALUE;

 @Override
 public boolean onTouchEvent(MotionEvent event) {
// super.onTouchEvent(event);
 Log.d(TAG, "[onTouchEvent]ev action: " + event.getAction());
 switch (event.getAction()) {
  case MotionEvent.ACTION_DOWN:
  downY = event.getY();
  Log.d(TAG, "Down --> downY: " + downY);
  requestDisallowInterceptTouchEvent(true); // 保證事件可往下傳遞
  break;
  case MotionEvent.ACTION_MOVE:

  float curY = event.getY();
  float deltaY = curY - downY;
  // 是否是有效的往下拖動事件（則需要顯示加載header）
  boolean isDropDownValidate = Float.MAX_VALUE != downY;
  /**
   * 修改攔截設置
   * 如果是有效往下拖動事件，則事件需要在本ViewGroup中處理，所以需要攔截不往子控件傳遞，即不允許攔截設為false
   * 如果不是有效往下拖動事件，則事件傳遞給子控件處理，所以不需要攔截，並往子控件傳遞，即不允許攔截設為true
   */
  requestDisallowInterceptTouchEvent(!isDropDownValidate);

  downY = curY;
  Log.d(TAG, "Move --> deltaY(curY - downY): " + deltaY);
  int curHeight = refreshHeaderView.getMeasuredHeight();
  int exceptHeight = curHeight + (int) (deltaY / 2);

  // 如果當前沒有處在正在刷新狀態，則更新刷新狀態
  if (STATE_REFRESHING != refreshState) {
   if (curHeight >= refreshArrivedStateHeight) { // 達到可刷新狀態
   setRefreshState(STATE_REFRESH_ARRIVED);
   } else { // 未達到可刷新狀態
   setRefreshState(STATE_REFRESH_NOT_ARRIVED);
   }
  }
  if (isDropDownValidate) {
   changeViewHeight(refreshHeaderView, Math.max(refreshNormalHeight, exceptHeight));
  } else { // 防止從子控件修改攔截後引發的downY為Float.MAX_VALUE的問題
   changeViewHeight(refreshHeaderView, Math.max(curHeight, exceptHeight));
  }

  break;
  case MotionEvent.ACTION_UP:
  downY = Float.MAX_VALUE;
  Log.d(TAG, "Up --> downY: " + downY);
  requestDisallowInterceptTouchEvent(true); // 保證事件可往下傳遞
  // 如果是達到刷新狀態，則設置正在刷新狀態的高度
  if (STATE_REFRESH_ARRIVED == refreshState) { // 達到了刷新的狀態
   startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshingHeight);
   setRefreshState(STATE_REFRESHING);
  } else if (STATE_REFRESHING == refreshState) { // 正在刷新的狀態
   startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshingHeight);
  } else {
   // 執行動畫後回歸正常狀態
   startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshNormalHeight, normalAnimatorListener);
  }

  break;
  case MotionEvent.ACTION_CANCEL:
  Log.d(TAG, "cancel");
  break;
 }
 return true;
 }

 /**
 * 刷新完畢後調用此方法
 */
 public void onCompleteRefresh() {
 if (STATE_REFRESHING == refreshState) {
  setRefreshState(STATE_REFRESH_NORMAL);
  startHeightAnimation(refreshHeaderView, refreshHeaderView.getMeasuredHeight(), refreshNormalHeight);
 }
 }

 /**
 * 修改當前的刷新狀態
 *
 * @param expectRefreshState
 */
 private void setRefreshState(int expectRefreshState) {
 if (expectRefreshState != refreshState) {
  refreshState = expectRefreshState;
  if (null != refreshableHelper) {
  refreshableHelper.onRefreshStateChanged(refreshHeaderView, refreshState);
  }
 }
 }


 /**
 * 改變某控件的高度
 *
 * @param view
 * @param height
 */
 private void changeViewHeight(View view, int height) {
 Log.d(TAG, "[changeViewHeight]change Height: " + height);
 ViewGroup.LayoutParams lp = view.getLayoutParams();
 lp.height = height;
 view.setLayoutParams(lp);
 }

 /**
 * 改變某控件的高度動畫
 *
 * @param view
 * @param fromHeight
 * @param toHeight
 */
 private void startHeightAnimation(final View view, int fromHeight, int toHeight) {
 startHeightAnimation(view, fromHeight, toHeight, null);
 }

 private void startHeightAnimation(final View view, int fromHeight, int toHeight, Animator.AnimatorListener animatorListener) {
 if (toHeight == view.getMeasuredHeight()) {
  return;
 }
 ValueAnimator heightAnimator = ValueAnimator.ofInt(fromHeight, toHeight);
 heightAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
  @Override
  public void onAnimationUpdate(ValueAnimator valueAnimator) {
  Integer value = (Integer) valueAnimator.getAnimatedValue();
  if (null == value) return;
  changeViewHeight(view, value);
  }
 });
 if (null != animatorListener) {
  heightAnimator.addListener(animatorListener);
 }
 heightAnimator.setInterpolator(new LinearInterpolator());
 heightAnimator.setDuration(300/*ms*/);
 heightAnimator.start();
 }

 AnimatorListenerAdapter normalAnimatorListener = new AnimatorListenerAdapter() {
 @Override
 public void onAnimationEnd(Animator animation) {
  super.onAnimationEnd(animation);
  setRefreshState(STATE_REFRESH_NORMAL); // 回歸正常狀態
 }
 };

 public void setRefreshArrivedStateHeight(int refreshArrivedStateHeight) {
 this.refreshArrivedStateHeight = refreshArrivedStateHeight;
 }

 public void setRefreshingHeight(int refreshingHeight) {
 this.refreshingHeight = refreshingHeight;
 }

 public void setRefreshNormalHeight(int refreshNormalHeight) {
 this.refreshNormalHeight = refreshNormalHeight;
 }

 public int getOriginRefreshHeight() {
 return originRefreshHeight;
 }
}

RefreshableHelper.java代碼:

package refreshableview.refreshablehelper;

import android.view.View;


public interface RefreshableHelper {
 /**
 * 初始化刷新View
 *
 * @return
 */
 View onInitRefreshHeaderView();

 /**
 * 初始化各個尺寸高度
 *
 * @param originRefreshHeight
 * @return
 */
 boolean onInitRefreshHeight(int originRefreshHeight);

 /**
 * 刷新狀態改變
 *
 * @param refreshView
 * @param refreshState
 */
 void onRefreshStateChanged(View refreshView, int refreshState);
}

main.xml內容:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:rv="http://schemas.android.com/tools"
 android:orientation="vertical"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent">
 <refreshableview.RefreshableView
  android:id="@+id/main_refresh_view"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  rv:interceptAllMoveEvents="false"
  >
 <refreshableview.NestScrollView android:layout_width="match_parent" android:layout_height="wrap_content"
  android:fillViewport="true"
  >

  <TextView
   android:id="@+id/main_tv"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:gravity="center"
   android:padding="20dp"
   android:textSize="18sp"
   android:text="下拉刷新\n\n\n\n\n\n\n\n\n\n\n下拉刷新\n下拉刷新\n\n\n\n\n\n\n\n\n\n\n下拉刷新\n下拉刷新\n\n\n\n\n\n\n\n\n\n\n下拉刷新\n下拉刷新\n\n\n\n\n\n\n\n\n\n\n下拉刷新---下拉刷新\n\n\n\n\n\n\n\n\n\n\n"
   />

 </refreshableview.NestScrollView>
 </refreshableview.RefreshableView>

</LinearLayout>

activity_refreshable_list.xml內容:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
 android:paddingLeft="@dimen/activity_horizontal_margin"
 android:paddingRight="@dimen/activity_horizontal_margin"
 android:paddingTop="@dimen/activity_vertical_margin"
 tools:context="siso.refreshablev.RefreshableListActivity">

</RelativeLayout>

refresh_head.xml內容:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="70dp"
  android:gravity="center"
  android:background="#aa000000"
 >
 <TextView
  android:id="@+id/refresh_head_tv"
  android:layout_width="fill_parent"
  android:layout_height="70dp"
  android:gravity="center"
  android:background="#aabbcc"
  android:textSize="18sp"
  android:text="refreshing"
  />

</LinearLayout>

refreshable_list.xml內容:

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


 <refreshableview.RefreshableListView
  android:id="@+id/refreshable_lv"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:cacheColorHint="@android:color/transparent"
  />

</LinearLayout>

運行結果如圖：

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持本站。