我在PageViewer中实现了一个GridView,但是滚动并不像它应该的那样平滑. GridView内部的视图正在拦截触摸.
这让我抓狂,我已经尝试了所有的东西,虽然有一件事情起作用,但最终并不是一个好的解决方案.首先是我的代码.
apps_grid.xml
<?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="match_parent"
android:orientation="vertical">
<GridView
android:id="@+id/appGrid"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/ic_launcher_background"
android:horizontalSpacing="4dp"
android:numColumns="4"
android:paddingTop="10dp"
android:stretchMode="columnWidth"
android:verticalSpacing="15dp"/>
</LinearLayout>
app_item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<ImageView
android:id="@+id/icon"
android:layout_width="54dp"
android:layout_height="54dp"
android:layout_gravity="center_horizontal"
android:src="@mipmap/ic_launcher" />
<TextView
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="5dp"
android:ellipsize="end"
android:gravity="center"
android:paddingEnd="15dp"
android:paddingStart="15dp"
android:singleLine="true"
android:text="title"
android:textColor="@android:color/white"
android:textSize="14sp" />
</LinearLayout>
activity_main.xml中
<android.support.v4.view.ViewPager
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="45dp"
android:fillViewport="true"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
/>
AppModel.java
public class AppModel {
private String label;
private String pkg;
private Drawable mIcon;
public AppModel(String name,String pkg,Drawable icon) {
this.label = name;
this.pkg = pkg;
this.mIcon = icon;
}
public AppModel(String name) {
this.label = name;
}
public String getLabel() {
return this.label;
}
public String getPkg() {
return this.pkg;
}
public Drawable getIcon() {
return mIcon;
}
}
AppListAdapter.java
public class AppListAdapter extends BaseAdapter {
private ArrayList<AppModel> apps;
private LayoutInflater layoutInflater;
public AppListAdapter(Context context,ArrayList<AppModel> apps) {
this.apps = apps;
this.layoutInflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
return apps.size();
}
@Override
public long getItemId(int position) {
return 0;
}
@Override
public Object getItem(int position) {
AppModel app = apps.get(position);
if(app == null) {
return null;
}
return app;
}
@Override
public View getView(int position,View convertView,ViewGroup parent) {
AppModel app = apps.get(position);
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.app_item,null);
}
if(app == null) {
return convertView;
}
((TextView)convertView.findViewById(R.id.text)).setText(app.getLabel());
return convertView;
}
}
TestPagerAdapter.java
public class TestPagerAdapter extends PagerAdapter {
private Context mContext;
private LayoutInflater inflater;
private ArrayList<AppModel> apps;
private int perPage = 12;
public TestPagerAdapter(Context context) {
this.mContext = context;
this.inflater = LayoutInflater.from(context);
}
@Override
public Object instantiateItem(ViewGroup parent,int position) {
ViewGroup layout = (ViewGroup) inflater.inflate(R.layout.apps_grid,parent,false);
ArrayList<AppModel> pageApps = getAppsForPage(position);
if(pageApps == null) {
return layout;
}
final GridView appGrid = (GridView) layout.findViewById(R.id.appGrid);
final AppListAdapter gridAdapter = new AppListAdapter(mContext,pageApps);
appGrid.setVerticalScrollBarEnabled(false);
appGrid.setAdapter(gridAdapter);
parent.addView(layout);
return layout;
}
@Override
public void destroyItem(ViewGroup parent,int position,Object view) {
parent.removeView((View) view);
}
@Override
public int getCount() {
if(apps != null) {
return (int) Math.ceil((double) apps.size() / perPage);
} else {
return 0;
}
}
@Override
public boolean isViewFromObject(View view,Object object) {
return view == object;
}
public void setData(ArrayList<AppModel> data) {
if(data != null) {
this.apps = data;
}
}
public ArrayList<AppModel> getAppsForPage(int page) {
if(apps == null) {
return null;
}
int size = apps.size();
int offset = getOffset(page);
ArrayList<AppModel> pageApps = new ArrayList<AppModel>(size);
for(int i = 0; i < perPage; i++) {
if(offset+i < size) {
pageApps.add(apps.get(offset+i));
}
}
return pageApps;
}
public int getOffset(int page) {
return perPage*page;
}
}
MainActivity.java
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
TestPagerAdapter mPAdapter = new TestPagerAdapter(this);
viewPager.setAdapter(mPAdapter);
ArrayList<AppModel> items = new ArrayList<AppModel>(20);
for(int i=0;i<20;i++) {
AppModel app = new AppModel(""+i);
items.add(app);
}
mPAdapter.setData(items);
mPAdapter.notifyDataSetChanged();
}
所以,这是我尝试过的：
我用RecyclerView替换了GridView.
在EVERY View上添加了所有这些属性
android:clickable="false" android:contextClickable="false" android:defaultFocusHighlightEnabled="false" android:focusable="false" android:focusableInTouchMode="false" android:focusedByDefault="false" android:isScrollContainer="false" android:longClickable="false" android:nestedScrollingEnabled="false" android:overScrollMode="never" android:touchscreenBlocksFocus="false"
在GridView上覆盖OnTouchListener(以及许多其他)并返回true.
可能尝试了一些我现在记不住的其他事情了.
唯一有效的是在GridView上设置android：filterTouchesWhenObscured =“true”属性,而其他一些应用程序视图位于顶部(所以条件“WhenObscured”满足)
当我尝试这个时,我的ViewPager开始非常流畅地滚动,在其他情况下它有时不会滚动(可能是当GridView拦截它时).
请注意,GridView中的项目必须是可点击的.
UPDATE
https://github.com/mpa4hu/GridViewPager这是项目的github链接,用类似于这张图片的手势模拟向前和向后滚动的问题
解决方法
Recycler视图会回收视图,并且在需要之前不会重新创建视图.它只是重新绑定视图.
RecyclerView是作为ListView改进创建的,所以是的,您可以使用ListView控件创建附加列表,但使用RecyclerView更容易：
在向上/向下滚动时重用单元格 – 这可以通过在listView适配器中实现View Holder来实现,但它是可选的,而在RecycleView中它是编写适配器的默认方式.
将列表与其容器分离 – 因此您可以使用设置LayoutManager在运行时轻松地将列表项放在不同的容器(linearLayout,gridLayout)中.
例：
mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view); mRecyclerView.setLayoutManager(new LinearLayoutManager(this)); //or mRecyclerView.setLayoutManager(new GridLayoutManager(this,2));//number of columns in a grid layout
有关RecyclerView的更多信息,但我认为这些是主要的.
因此,总而言之,RecyclerView是一种更灵活的控制,用于处理“列表数据”,遵循关注委托模式,并为自己留下一个任务 – 回收项目.
你可以在这里参考它的优点：RecyclerView over ListView
