Listviewによるドロップダウン・リフレッシュ
listview、PullToRefreshListViewを書き換えます.java
使用方法:
pull_to_refresh_header_other.xml:
string.xmlに追加:
Tools.getTime():
説明:
refresharrow.pngは下向きの矢印で、
images_bg.pngはドロップダウンリフレッシュの背景画像です
@style/reflushProgressStyleはロードスタイルです
ActivityではOnRefreshListenerインタフェースを実装し、onRefresh()メソッドでデータのロード操作を行う必要があるが、非同期方式を採用し、ロード後にonRefreshComplete()メソッドを呼び出すことが望ましい
なお、ドロップダウンリフレッシュはlistviewのヘッダに1、activityでデータをロードした後、アダプタnotifyDataSet Changedの後、listviewのsetSelection(1)を実行し、ページに入ったばかりのときにドロップダウンリフレッシュが非表示になる.2、listviewの長押し操作を傍受したり、クリック操作をしたりして、データを取得する際にpositionが-13を必要としていることを覚えておいて、データ量が少ない場合、listviewが1ページで表示され終わると、ドロップダウン・リフレッシュが表示され、良い方法はしばらく考えられませんでしたが、しかし、アダプタでのgetCountメソッド:public int getCount(){if(list!=null){if(list.size()<6){return 6;}else{ return list.size() ; } } else { return 0; } } 私が書いたページlistviewには一般的に5-6個のデータが表示されるので、この値より少ない値ではデフォルトで6個が返されます.これによりlistviewがページをいっぱいにして、ドロップダウン・リフレッシュを隠す目的を達成することができます.getviewメソッドでは、if(position<=list.size()-1){convertView.setVisibility(View.VISIBLE); } else { convertView.setVisibility(View.INVISIBLE); } 同時にlistviewコントロールでandroid:scrollbars="none"android:divider="@null"android:dividerHeight="2 dip"android:cacheColorHint="00000000"を設定
import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.view.animation.RotateAnimation;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ImageView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.RelativeLayout;
import android.widget.TextView;
import com.zsx.youliao.R;
import com.zsx.youliao.util.Mylog;
import com.zsx.youliao.util.Tools;
public class PullToRefreshListView extends ListView implements OnScrollListener {
private static final int TAP_TO_REFRESH = 1;
private static final int PULL_TO_REFRESH = 2;
private static final int RELEASE_TO_REFRESH = 3;
private static final int REFRESHING = 4;
private static final String TAG = "PullToRefreshListView";
private OnRefreshListener mOnRefreshListener;
/**
* Listener that will receive notifications every time the list scrolls.
*/
private OnScrollListener mOnScrollListener;
private LayoutInflater mInflater;
private RelativeLayout mRefreshView;
private TextView mRefreshViewText;
private ImageView mRefreshViewImage;
private ProgressBar mRefreshViewProgress;
private TextView mRefreshViewLastUpdated;
private int mCurrentScrollState;
private int mRefreshState;
private RotateAnimation mFlipAnimation;
private RotateAnimation mReverseFlipAnimation;
private int mRefreshViewHeight;
private int mRefreshOriginalTopPadding;
private int mLastMotionY;
private boolean mBounceHack;
public PullToRefreshListView(Context context) {
super(context);
init(context);
}
public PullToRefreshListView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
public PullToRefreshListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}
private void init(Context context) {
Mylog.i(TAG, "init");
// Load all of the animations we need in code rather than through XML
mFlipAnimation = new RotateAnimation(0, -180,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
mFlipAnimation.setInterpolator(new LinearInterpolator());
mFlipAnimation.setDuration(250);
mFlipAnimation.setFillAfter(true);
mReverseFlipAnimation = new RotateAnimation(-180, 0,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
mReverseFlipAnimation.setInterpolator(new LinearInterpolator());
mReverseFlipAnimation.setDuration(250);
mReverseFlipAnimation.setFillAfter(true);
mInflater = (LayoutInflater) context.getSystemService(
Context.LAYOUT_INFLATER_SERVICE);
mRefreshView = (RelativeLayout) mInflater.inflate(
R.layout.pull_to_refresh_header_other, this, false);
mRefreshViewText =
(TextView) mRefreshView.findViewById(R.id.pull_to_refresh_text);
mRefreshViewImage =
(ImageView) mRefreshView.findViewById(R.id.pull_to_refresh_image);
mRefreshViewProgress =
(ProgressBar) mRefreshView.findViewById(R.id.pull_to_refresh_progress);
mRefreshViewLastUpdated =
(TextView) mRefreshView.findViewById(R.id.pull_to_refresh_updated_at);
mRefreshViewImage.setMinimumHeight(50);
mRefreshView.setOnClickListener(new OnClickRefreshListener());
mRefreshOriginalTopPadding = mRefreshView.getPaddingTop();
mRefreshState = TAP_TO_REFRESH;
addHeaderView(mRefreshView);
super.setOnScrollListener(this);
measureView(mRefreshView);
mRefreshViewHeight = mRefreshView.getMeasuredHeight();
setLastUpdated(getResources().getString(R.string.string_flush_lasttime)+Tools.getTime());
}
@Override
protected void onAttachedToWindow() {
setSelection(1);
}
@Override
public void setAdapter(ListAdapter adapter) {
super.setAdapter(adapter);
setSelection(1);
}
/**
* Set the listener that will receive notifications every time the list
* scrolls.
*
* @param l The scroll listener.
*/
@Override
public void setOnScrollListener(AbsListView.OnScrollListener l) {
mOnScrollListener = l;
}
/**
* Register a callback to be invoked when this list should be refreshed.
*
* @param onRefreshListener The callback to run.
*/
public void setOnRefreshListener(OnRefreshListener onRefreshListener) {
mOnRefreshListener = onRefreshListener;
}
/**
* Set a text to represent when the list was last updated.
* @param lastUpdated Last updated at.
*/
public void setLastUpdated(CharSequence lastUpdated) {
if (lastUpdated != null) {
mRefreshViewLastUpdated.setVisibility(View.VISIBLE);
mRefreshViewLastUpdated.setText(lastUpdated);
} else {
mRefreshViewLastUpdated.setVisibility(View.GONE);
}
}
@Override
public boolean onTouchEvent(MotionEvent event) {
final int y = (int) event.getY();
mBounceHack = false;
switch (event.getAction()) {
case MotionEvent.ACTION_UP:
if (!isVerticalScrollBarEnabled()) {
setVerticalScrollBarEnabled(true);
}
if (getFirstVisiblePosition() == 0 && mRefreshState != REFRESHING) {
if ((mRefreshView.getBottom() >= mRefreshViewHeight
|| mRefreshView.getTop() >= 0)
&& mRefreshState == RELEASE_TO_REFRESH) {
// Initiate the refresh
mRefreshState = REFRESHING;
prepareForRefresh();
onRefresh();
} else if (mRefreshView.getBottom() < mRefreshViewHeight
|| mRefreshView.getTop() <= 0) {
// Abort refresh and scroll down below the refresh view
resetHeader();
setSelection(1);
}
}
break;
case MotionEvent.ACTION_DOWN:
mLastMotionY = y;
break;
case MotionEvent.ACTION_MOVE:
applyHeaderPadding(event);
break;
}
return super.onTouchEvent(event);
}
private void applyHeaderPadding(MotionEvent ev) {
// getHistorySize has been available since API 1
int pointerCount = ev.getHistorySize();
for (int p = 0; p < pointerCount; p++) {
if (mRefreshState == RELEASE_TO_REFRESH) {
if (isVerticalFadingEdgeEnabled()) {
setVerticalScrollBarEnabled(false);
}
int historicalY = (int) ev.getHistoricalY(p);
// Calculate the padding to apply, we divide by 1.7 to
// simulate a more resistant effect during pull.
int topPadding = (int) (((historicalY - mLastMotionY)
- mRefreshViewHeight) / 1.7);
mRefreshView.setPadding(
mRefreshView.getPaddingLeft(),
topPadding,
mRefreshView.getPaddingRight(),
mRefreshView.getPaddingBottom());
}
}
}
/**
* Sets the header padding back to original size.
*/
private void resetHeaderPadding() {
mRefreshView.setPadding(
mRefreshView.getPaddingLeft(),
mRefreshOriginalTopPadding,
mRefreshView.getPaddingRight(),
mRefreshView.getPaddingBottom());
}
/**
* Resets the header to the original state.
*/
private void resetHeader() {
if (mRefreshState != TAP_TO_REFRESH) {
mRefreshState = TAP_TO_REFRESH;
resetHeaderPadding();
// Set refresh view text to the pull label
mRefreshViewText.setText(R.string.pull_to_refresh_pull_label);
// Replace refresh drawable with arrow drawable
mRefreshViewImage.setImageResource(R.drawable.refresharrow);
// Clear the full rotation animation
mRefreshViewImage.clearAnimation();
// Hide progress bar and arrow.
mRefreshViewImage.setVisibility(View.GONE);
mRefreshViewProgress.setVisibility(View.GONE);
}
}
private void measureView(View child) {
ViewGroup.LayoutParams p = child.getLayoutParams();
if (p == null) {
p = new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.FILL_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
}
int childWidthSpec = ViewGroup.getChildMeasureSpec(0,
0 + 0, p.width);
int lpHeight = p.height;
int childHeightSpec;
if (lpHeight > 0) {
childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight, MeasureSpec.EXACTLY);
} else {
childHeightSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
}
child.measure(childWidthSpec, childHeightSpec);
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
// When the refresh view is completely visible, change the text to say
// "Release to refresh..." and flip the arrow drawable.
if (mCurrentScrollState == SCROLL_STATE_TOUCH_SCROLL
&& mRefreshState != REFRESHING) {
if (firstVisibleItem == 0) {
mRefreshViewImage.setVisibility(View.VISIBLE);
if ((mRefreshView.getBottom() >= mRefreshViewHeight + 20
|| mRefreshView.getTop() >= 0)
&& mRefreshState != RELEASE_TO_REFRESH) {
mRefreshViewText.setText(R.string.pull_to_refresh_release_label);
mRefreshViewImage.clearAnimation();
mRefreshViewImage.startAnimation(mFlipAnimation);
mRefreshState = RELEASE_TO_REFRESH;
} else if (mRefreshView.getBottom() < mRefreshViewHeight + 20
&& mRefreshState != PULL_TO_REFRESH) {
mRefreshViewText.setText(R.string.pull_to_refresh_pull_label);
if (mRefreshState != TAP_TO_REFRESH) {
mRefreshViewImage.clearAnimation();
mRefreshViewImage.startAnimation(mReverseFlipAnimation);
}
mRefreshState = PULL_TO_REFRESH;
}
} else {
mRefreshViewImage.setVisibility(View.GONE);
resetHeader();
}
} else if (mCurrentScrollState == SCROLL_STATE_FLING
&& firstVisibleItem == 0
&& mRefreshState != REFRESHING) {
setSelection(1);
mBounceHack = true;
} else if (mBounceHack && mCurrentScrollState == SCROLL_STATE_FLING) {
setSelection(1);
}
if (mOnScrollListener != null) {
mOnScrollListener.onScroll(view, firstVisibleItem,
visibleItemCount, totalItemCount);
}
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
mCurrentScrollState = scrollState;
if (mCurrentScrollState == SCROLL_STATE_IDLE) {
mBounceHack = false;
}
if (mOnScrollListener != null) {
mOnScrollListener.onScrollStateChanged(view, scrollState);
}
}
public void prepareForRefresh() {
resetHeaderPadding();
mRefreshViewImage.setVisibility(View.GONE);
// We need this hack, otherwise it will keep the previous drawable.
mRefreshViewImage.setImageDrawable(null);
mRefreshViewProgress.setVisibility(View.VISIBLE);
// Set refresh view text to the refreshing label
mRefreshViewText.setText(R.string.pull_to_refresh_refreshing_label);
mRefreshState = REFRESHING;
}
public void onRefresh() {
Mylog.d(TAG, "onRefresh");
if (mOnRefreshListener != null) {
mOnRefreshListener.onRefresh();
}
}
/**
* Resets the list to a normal state after a refresh.
* @param lastUpdated Last updated at.
*/
public void onRefreshComplete(CharSequence lastUpdated) {
setLastUpdated(lastUpdated);
onRefreshComplete();
}
/**
* Resets the list to a normal state after a refresh.
*/
public void onRefreshComplete() {
Mylog.d(TAG, "onRefreshComplete");
resetHeader();
// If refresh view is visible when loading completes, scroll down to
// the next item.
if (mRefreshView.getBottom() > 0) {
invalidateViews();
setSelection(1);
}
}
/**
* Invoked when the refresh view is clicked on. This is mainly used when
* there's only a few items in the list and it's not possible to drag the
* list.
*/
private class OnClickRefreshListener implements OnClickListener {
@Override
public void onClick(View v) {
if (mRefreshState != REFRESHING) {
prepareForRefresh();
onRefresh();
}
}
}
/**
* Interface definition for a callback to be invoked when list should be
* refreshed.
*/
public interface OnRefreshListener {
/**
* Called when the list should be refreshed.
* <p>
* A call to {@link PullToRefreshListView #onRefreshComplete()} is
* expected to indicate that the refresh has completed.
*/
public void onRefresh();
}
}使用方法:
< .PullToRefreshListView
android:id="@+id/friend_list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:scrollbars="none"
android:divider="@null"
android:dividerHeight="2dip"
android:cacheColorHint="#00000000"
/>pull_to_refresh_header_other.xml:
<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (C) 2011 Johan Nilsson <http://markupartist.com>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingTop="10dip"
android:paddingBottom="15dip"
android:background="@drawable/images_bg"
android:gravity="center"
android:id="@+id/pull_to_refresh_header"
>
<ProgressBar
android:id="@+id/pull_to_refresh_progress"
android:indeterminate="true"
android:layout_width="18dip"
android:layout_height="18dip"
android:layout_marginLeft="30dip"
android:layout_marginRight="20dip"
android:layout_marginTop="20dip"
android:layout_marginBottom="10dip"
android:visibility="gone"
android:layout_centerVertical="true"
style="@style/reflushProgressStyle"
/>
<ImageView
android:id="@+id/pull_to_refresh_image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="30dip"
android:layout_marginRight="20dip"
android:visibility="gone"
android:layout_gravity="center"
android:gravity="center"
android:src="@drawable/refresharrow"
/>
<TextView
android:id="@+id/pull_to_refresh_text"
android:text="@string/pull_to_refresh_pull_label"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textStyle="bold"
android:paddingTop="5dip"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
/>
<TextView
android:id="@+id/pull_to_refresh_updated_at"
android:layout_below="@+id/pull_to_refresh_text"
android:visibility="visible"
android:textAppearance="?android:attr/textAppearanceSmall"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
/>
</RelativeLayout>string.xmlに追加:
<string name="pull_to_refresh_pull_label"> </string>
<string name="pull_to_refresh_release_label"> </string>
<string name="pull_to_refresh_refreshing_label"> ...</string>
<string name="string_flush_lasttime"> :</string>Tools.getTime():
public static String getTime() {
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date curDate = new Date(System.currentTimeMillis());//
String str = formatter.format(curDate);
return str;
}説明:
refresharrow.pngは下向きの矢印で、
images_bg.pngはドロップダウンリフレッシュの背景画像です
@style/reflushProgressStyleはロードスタイルです
ActivityではOnRefreshListenerインタフェースを実装し、onRefresh()メソッドでデータのロード操作を行う必要があるが、非同期方式を採用し、ロード後にonRefreshComplete()メソッドを呼び出すことが望ましい
なお、ドロップダウンリフレッシュはlistviewのヘッダに1、activityでデータをロードした後、アダプタnotifyDataSet Changedの後、listviewのsetSelection(1)を実行し、ページに入ったばかりのときにドロップダウンリフレッシュが非表示になる.2、listviewの長押し操作を傍受したり、クリック操作をしたりして、データを取得する際にpositionが-13を必要としていることを覚えておいて、データ量が少ない場合、listviewが1ページで表示され終わると、ドロップダウン・リフレッシュが表示され、良い方法はしばらく考えられませんでしたが、しかし、アダプタでのgetCountメソッド:public int getCount(){if(list!=null){if(list.size()<6){return 6;}else{ return list.size() ; } } else { return 0; } } 私が書いたページlistviewには一般的に5-6個のデータが表示されるので、この値より少ない値ではデフォルトで6個が返されます.これによりlistviewがページをいっぱいにして、ドロップダウン・リフレッシュを隠す目的を達成することができます.getviewメソッドでは、if(position<=list.size()-1){convertView.setVisibility(View.VISIBLE); } else { convertView.setVisibility(View.INVISIBLE); } 同時にlistviewコントロールでandroid:scrollbars="none"android:divider="@null"android:dividerHeight="2 dip"android:cacheColorHint="00000000"を設定