Waterfall streams that can be pulled and refreshed and loaded up and down

Waterfall streams that can be pulled and refreshed and loaded up and down
The waterfall was very popular when it first came out, and everyone thought it was amazing, so I also played it. But as a result, when it was applied to specific scenarios, we need to use the pull-up refresh function, and the open-source effect cannot be achieved. Therefore, after great guidance, we have re-implemented this effect.
First, we need to reference the waterfall Stream project. github Project address: waterfall.
Then we introduce the pull-down refresh project. github Project address: Release. We need to modify the PullToRefreshBase. java class and add two methods to determine whether the PullToRefreshBase is pulled up or pulled down.

public boolean isHeaderShown() {return getHeaderLayout().isShown();}public boolean isFooterShown() {return getFooterLayout().isShown();      }

So far, the reference of the project library has been completed. Next, we need to customize the PullToRefreshStaggeredGridView class to merge the waterfall stream and refresh component.

import android.annotation.SuppressLint;import android.annotation.TargetApi;import android.content.Context;import android.os.Build.VERSION;import android.os.Build.VERSION_CODES;import android.os.Bundle;import android.util.AttributeSet;import android.view.View;import com.etsy.android.grid.StaggeredGridView;import com.handmark.pulltorefresh.library.OverscrollHelper;import com.handmark.pulltorefresh.library.PullToRefreshBase;import com.handmark.pulltorefresh.library.R;@SuppressLint("NewApi")public class PullToRefreshStaggeredGridView extendsPullToRefreshBase<StaggeredGridView> {private static final OnRefreshListener<StaggeredGridView> defaultOnRefreshListener = new OnRefreshListener<StaggeredGridView>() {@Overridepublic void onRefresh(PullToRefreshBase<StaggeredGridView> refreshView) {}};public PullToRefreshStaggeredGridView(Context context) {super(context);/** * Added so that by default, Pull-to-Refresh refreshes the page */setOnRefreshListener(defaultOnRefreshListener);}public PullToRefreshStaggeredGridView(Context context, AttributeSet attrs) {super(context, attrs);/** * Added so that by default, Pull-to-Refresh refreshes the page */setOnRefreshListener(defaultOnRefreshListener);}public PullToRefreshStaggeredGridView(Context context, Mode mode) {super(context, mode);/** * Added so that by default, Pull-to-Refresh refreshes the page */setOnRefreshListener(defaultOnRefreshListener);}public PullToRefreshStaggeredGridView(Context context, Mode mode,AnimationStyle style) {super(context, mode, style);/** * Added so that by default, Pull-to-Refresh refreshes the page */setOnRefreshListener(defaultOnRefreshListener);}@Overridepublic final Orientation getPullToRefreshScrollDirection() {return Orientation.VERTICAL;}@Overrideprotected StaggeredGridView createRefreshableView(Context context,AttributeSet attrs) {StaggeredGridView gridView;if (VERSION.SDK_INT >= VERSION_CODES.GINGERBREAD) {gridView = new InternalStaggeredGridViewSDK9(context, attrs);} else {gridView = new StaggeredGridView(context, attrs);}gridView.setId(R.id.gridview);return gridView;}@Overrideprotected boolean isReadyForPullStart() {boolean result = false;View v = getRefreshableView().getChildAt(0);if (getRefreshableView().getFirstVisiblePosition() == 0) {if (v != null) {// getTop() and getBottom() are relative to the ListView,// so if getTop() is negative, it is not fully visibleboolean isTopFullyVisible = v.getTop() >= 0;result = isTopFullyVisible;}}return result;}@Overrideprotected boolean isReadyForPullEnd() {boolean result = false;int last = getRefreshableView().getChildCount() - 1;View v = getRefreshableView().getChildAt(last);int firstVisiblePosition = getRefreshableView().getFirstVisiblePosition();int visibleItemCount = getRefreshableView().getChildCount();int itemCount = getRefreshableView().getAdapter().getCount();if (firstVisiblePosition + visibleItemCount >= itemCount) {if (v != null) {boolean isLastFullyVisible = v.getBottom() <= getRefreshableView().getHeight();result = isLastFullyVisible;}}return result;}@Overrideprotected void onPtrRestoreInstanceState(Bundle savedInstanceState) {super.onPtrRestoreInstanceState(savedInstanceState);}@Overrideprotected void onPtrSaveInstanceState(Bundle saveState) {super.onPtrSaveInstanceState(saveState);}@TargetApi(9)final class InternalStaggeredGridViewSDK9 extends StaggeredGridView {// WebView doesn't always scroll back to it's edge so we add some// fuzzinessstatic final int OVERSCROLL_FUZZY_THRESHOLD = 2;// WebView seems quite reluctant to overscroll so we use the scale// factor to scale it's valuestatic final float OVERSCROLL_SCALE_FACTOR = 1.5f;public InternalStaggeredGridViewSDK9(Context context, AttributeSet attrs) {super(context, attrs);}@Overrideprotected boolean overScrollBy(int deltaX, int deltaY, int scrollX,int scrollY, int scrollRangeX, int scrollRangeY,int maxOverScrollX, int maxOverScrollY, boolean isTouchEvent) {final boolean returnValue = super.overScrollBy(deltaX, deltaY,scrollX, scrollY, scrollRangeX, scrollRangeY,maxOverScrollX, maxOverScrollY, isTouchEvent);// Does all of the hard work...OverscrollHelper.overScrollBy(PullToRefreshStaggeredGridView.this,deltaX, scrollX, deltaY, getScrollRange(), isTouchEvent);return returnValue;}/** * Taken from the AOSP ScrollView source */private int getScrollRange() {int scrollRange = 0;if (getChildCount() > 0) {View child = getChildAt(0);scrollRange = Math.max(0, child.getHeight()- (getHeight() - getPaddingBottom() - getPaddingTop()));}return scrollRange;}}}

Then we customize the layout file and use the control we re-wrote

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:background="#FFF"    android:orientation="vertical" >    <com.thomas.pulltorefreshstaggeredgridview.PullToRefreshStaggeredGridView        android:id="@+id/pull_grid_view"        android:layout_width="match_parent"        android:layout_height="match_parent"        android:layout_margin="10dp"        android:background="#F0F0F0"        android:cacheColorHint="#00000000"        android:fadingEdge="none"        android:overScrollMode="never"        android:scrollbars="none"        app:column_count="2"        app:item_margin="8dp" /></LinearLayout>

Then we perform coding in activity

Import java. util. arrayList; import java. util. list; import android. annotation. suppressLint; import android. app. activity; import android. content. context; import android. OS. bundle; import com. etsy. android. grid. staggeredGridView; import com. handmark. pulltorefresh. library. pullToRefreshBase; import com. handmark. pulltorefresh. library. pullToRefreshBase. mode; import com. handmark. pulltorefresh. library. pullToRefreshBase. onRefreshListener; import com. nostra13.universalimageloader. cache. disc. naming. md5FileNameGenerator; import com. nostra13.universalimageloader. core. imageLoader; import com. nostra13.universalimageloader. core. imageLoaderConfiguration; import com. nostra13.universalimageloader. core. assist. queueProcessingType; @ SuppressLint ("NewApi") public class MainActivity extends Activity extends <StaggeredGridView> {private List <PhotoBean> photos; private StaggeredGridView mDongTaiGridView; private MyPhotoAdapter mAdapter; /** refresh **/private PullToRefreshStaggeredGridView mPullToRefreshStaggerdGridView; @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); initImageLoader (this); setContentView (R. layout. activity_main); photos = getPhotos (); mAdapter = new MyPhotoAdapter (this, photos); mPullToRefreshStaggerdGridView = (PullToRefreshStaggeredGridView) this. findViewById (R. id. pull_grid_view); mPullToRefreshStaggerdGridView. setMode (Mode. PULL_FROM_START); mPullToRefreshStaggerdGridView. setMode (Mode. BOTH); mPullToRefreshStaggerdGridView. setOnRefreshListener (this); mDongTaiGridView = mPullToRefreshStaggerdGridView. getRefreshableView (); mDongTaiGridView. setAdapter (mAdapter);} private List <PhotoBean> getPhotos () {List <PhotoBean> photos = new ArrayList <PhotoBean> (); PhotoBean = new PhotoBean ("http://img4q.duitang.com/uploads/item/201506/29/20150629140736_5JR8c.jpeg ", "Summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img5q.duitang.com/uploads/item/201506/29/20150629141607_LNFkx.thumb.700_0.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img5q.duitang.com/uploads/item/201506/29/20150629141550_MuVm5.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img5q.duitang.com/uploads/item/201506/29/20150629141740_TUB2H.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img4q.duitang.com/uploads/item/201506/29/20150629141716_nCUrG.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://cdnq.duitang.com/uploads/item/201506/29/20150629141656_5GBzS.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img4q.duitang.com/uploads/item/201506/29/20150629141634_CEida.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img5q.duitang.com/uploads/item/201506/29/20150629141236_sAHim.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img4q.duitang.com/uploads/item/201506/29/20150629141218_ezRd4.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://cdnq.duitang.com/uploads/item/201506/29/20150629141200_nykzY.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img4q.duitang.com/uploads/item/201506/29/20150629141125_FCtVN.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img4q.duitang.com/uploads/item/201506/29/20150629141108_mBrUc.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://cdnq.duitang.com/uploads/item/201506/29/20150629141052_cdFuA.thumb.700_0.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://cdnq.duitang.com/uploads/item/201506/29/20150629141030_zv2Rt.jpeg", "summer wind"); photos. add (PhotoBean); PhotoBean = new PhotoBean ("http://img5q.duitang.com/uploads/item/201506/29/20150629140948_UMWTQ.jpeg", "summer wind"); photos. add (PhotoBean); return photos ;}@ Overridepublic void onRefresh (PullToRefreshBase <StaggeredGridView> refreshView) {// TODO Auto-generated method stubif (refreshView. isHeaderShown () {} else {} public void initImageLoader (Context context) {ImageLoaderConfiguration config = new ImageLoaderConfiguration. builder (context ). threadPriority (Thread. NORM_PRIORITY-2 ). denyCacheImageMultipleSizesInMemory (). discCacheFileNameGenerator (new Md5FileNameGenerator ()). tasksProcessingOrder (QueueProcessingType. LIFO ). writeDebugLogs () // Remove for release app. build (); ImageLoader. getInstance (). init (config );}}

Next, see:


If you still have any questions, go to my github homepage and download the complete code demo.
Click Open Link

I will further complete the project on github and hope to improve it with you.

Copyright Disclaimer: This article is an original article by the blogger and cannot be reproduced without the permission of the blogger.