I'm creating an android app.There is an activity that shows application settings and user profile.So I create xml file like this.
<RelativeLayout>
<ScrollView>
<LinearLayout>
<LinearLayout>
//Layout for user profile
</LinearLayout>
<ListView>
//for application setting
</ListView>
</LinearLayout>
</ScrollView>
</RelativeLayout>
But ,as I read, nested ListView inside ScrollView is not good. "User Profile layout" is different from "Setting Layout". And there are many items inside "Setting ListView".So I must scroll both "profile layout" and "Settings " in order to get the bottom. I want to add settings(string and icon) programmatically. Are there some ways to achieve this?
Sorry for my bad English writing skill.
What you are looking for is RecyclerView adapter with different view holders for profile layout and settings layout.
For your reference enter link description here
You have to create/bind profile layout for position 0 and application setting layout for all the other positions in the RecyclerView Adapter.
Related
Everything is done i.e adapter is created, the layout is created and data is passed but when I add ListView to the main activity, then nothing appears. I think the problem is somewhere in xml. Please help
Activity2.xml
<ListView 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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.student.shopifysalespediasample.Activity2"
android:orientation="vertical"
android:id="#+id/list"
android:drawSelectorOnTop="true">
<!-- android:drawSelectorOnTop="true" shows a visual effect while clicking on listItem views-->
It shows blank screen instead of showing a sample list item in xml
tools:listitem | tools:listheader | tools:listfooter
These attributes are intended for <AdapterView> (and its subclasses like <ListView> and <RecyclerView>) and used to specify the layout that should be drawn inside that adapter as a list item, header or footer. For example, fragment_contacts_xml layout of our Contacts+ app declares <RecyclerView> and this is how it looks like before and after adding tools:listitem=”#layout/contact_item”
tools:itemCount
This attribute is intended solely for <RecyclerView> and used to specify the number of list items the layout editor should render in the layout preview.
By default Android Studio shows 10 list items for <RecyclerView>.
Therefore usually after adding tools:listitem attribute the <RecyclerView> covers the entire layout screen and you can no longer see other view elements below it. In such cases tools:itemCount attribute will help you to see the elements below the <RecyclerView>.
More you can find in hidden gems article.
You need to add ArrayAdapter or CustomAdapter along with list item layout to populate list view. If after adding adapter problem persists then please share complete code. Use this link for reference. https://www.vogella.com/tutorials/AndroidListView/article.html
tl;dr: How to achieve the layout shown in the screenshot below? Placing ListView to a ScrollView is apparently not recommended, but is there actually any other way to achieve it?
The whole question: I want to have multiple CardViews in my app, and one (or more) of them will have either RecyclerView or ListView in it (it doesn't really matter to me which one of those). The whole view is supposed to be scrollable - not only the ListViews in their parent CardViews. I basically need to achieve similar layout as the Play Store app has.
The first option I tried was this (the code is obviously simplified):
<LinearLayout android:orientation="vertical">
<CardView>
<!-- Some content of the first card. -->
</CardView>
<CardView>
<ListView/>
</CardView>
</LinearLayout>
The result was not what I wanted, the ListView was only scrollable in its parent CardView but the whole view wasn't scrollable like it is in the Play Store app. So now I wrapped it all in a ScrollView:
<ScrollView
android:fillViewport="true"
android:isScrollContainer="true">
<LinearLayout orientation="vertical">
<CardView>
<!-- Some content of the first card. -->
</CardView>
<CardView>
<ListView/>
</CardView>
</LinearLayout>
</ScrollView>
And I programmatically set the height of the bottom card to fit the ListView's height (number of elements in the ListView * height of one list item element). Now the whole view is scrollable, and the bottom card's height is the same as the height of the ListView, so the ListView isn't scrollable inside the CardView which is exactly what I wanted.
Now the actual problem: I got it working as described above, but I know this particular issue (ListView in a ScrollView) has been asked about many times before and the answer has always been the same - don't put neither RecyclerView nor ListView in a ScrollView because it causes performance problems. Well, so what's the correct approach then? How did Google do it in the Play Store app? I tried decompiling the Play Store app with APKTool but there weren't any layout files (maybe I did something wrong). Is my approach correct? My ListView will only display a few items (I guess it will be at most 20 items) - will it cause some performance issues in this case?
I wouldn't ask about this if all the answers wouldn't always mention that we shouldn't put ListView in a ScrollView. Is there any other way how to achieve the layout described by the screenshot above?
The first thing to address is why you're "not supposed to" use wrap_content on a ListView or a RecyclerView and put it in a scrollable container: it defeats the entire view-recycling purpose of these components.
What makes a ListView or RecyclerView better than a LinearLayout inside a ScrollView is that the system only needs to create enough views to display everying that fits inside the visible area. When you "scroll" the visible area, the views that disappear off one end can be re-used for the views that scroll into view from the other end. When you make your list/recycler wrap_content, this recycling is impossible, so you might as well just manually add your views to a LinearLayout instead.
That being said, RecyclerView does support using wrap_content... it just means you won't get view recycling. If this performance hit doesn't cause you problems, there's no objectively evil code here.
The only way to know for sure if the performance penalty is problematic or not is to just try it, test it, measure it, and decide for yourself. With 20 items, I suspect you have nothing to worry about.
The next thing to think about is the fact that Google has tons of resources and manpower and can afford to be extremely clever. Perhaps the Play Store app is as you say, with some sort of scrollable parent container that holds cards, each of which have some sort of adapter view within. But it's equally possible that they're doing something completely different, like using a single RecyclerView and "faking" the appearance of cards by using an ItemDecoration. Or perhaps they are using some sort of custom view subclass that the public doesn't have access to.
As for how you could recreate something similar, I suspect a hierarchy like this will work just fine:
<NestedScrollView>
<LinearLayout>
<CardView>
<RecyclerView/>
</CardView>
<CardView>
<RecyclerView/>
</CardView>
<CardView>
<RecyclerView/>
</CardView>
</LinearLayout>
</NestedScrollView>
I would recommend you to use Sectioned RecyclerView for this purpose. Every single item layout would have a cardView in it instead of creating a cardView as a parent.
Refer to this library: https://github.com/luizgrp/SectionedRecyclerViewAdapter
I'm trying to show a list of data in an android activity. Normally anyone would do that with a simple ListView which I have used many times before. But now I'm having an application with a fixed header and footer, with the middle part (the content) scrolling underneath both the header and the footer. In the middle section I would like to add other components both above and below the list of data, but the entire part must be scrollable. I tried adding components (like a button, textview etc) to a listview but the lay-out builder in Eclipse won't let me do that.
So I started using a ScrollView where you can easily add any component you like. But I am not allowed to add a ListView to a ScrollView, which I can understand as it would create a strange effect (as both are able to scroll).
Next I wanted to use a TableLayout to dynamically add TableRows, but on multiple websites it is said to be slow and 'not the way to do it'. I also couldn't find an elegant way to add the seperator between each item. With a ListView that would all be done very easily.
The following image probably explaines at best the effect I want: http://tinyurl.com/bvkec5d
The table with the 'Table Data' header can possibly have a lot of items and thus can become very large in length. What I don't want is that the table has a fixed size and the items are scrollable within that table. I actually want the table to grow in size and the ScrollView containing the table should therefore be growing as well. I also want the infobox above the table to scroll along (as with any other components which might be added later).
What is the best way to achieve this effect?
You can use a simple vertical LinearLayout (or a RelativeLayout) that contains your static header and footer, and use a ListView between them. You can set header and footer views on the ListView to add the scrollable header and footer content. For simplicity of example here's the LinearLayout way:
<LinearLayout android:orientation="vertical"
android:layout_height="match_parent"
android:layout_width="match_parent">
<!--static header content... can be any kind of view-->
<TextView
android:layout_width="match_parent"
android:layout_weight="0"
android:layout_height="wrap_content"/>
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
<!--static footer content... can be any kind of view-->
<TextView
android:layout_width="match_parent"
android:layout_weight="0"
android:layout_height="wrap_content"/>
</LinearLayout>
And in code, you can say:
ListView theList = (ListView)findViewById(R.id.list);
// example of creating header and footer views from inflation or by instantiation in code
View myHeaderView = getLayoutInflater().inflate(R.layout.myHeaderLayout,theList,false);
View myFooterView = new TextView(this, some layout params);
theList.addHeaderView(myHeaderView);
theList.addFooterView(myFooterView);
ListView.addHeaderView and ListView.addFooterView should enable you to add other static views (whose content could be updated dynamically) to the top or bottom of a ListView:
public void addHeaderView (View v)
Since: API Level 1 Add a fixed view to appear at the top of the list.
If addHeaderView is called more than once, the views will appear in
the order they were added. Views added using this call can take focus
if they want.
NOTE: Call this before calling setAdapter. This is so ListView can
wrap the supplied cursor with one that will also account for header
and footer views.
I have a layout requirement like below,
Textview
TextView
ListView
Edit Text
Button
Since listview cannot fit in landscape, I want to have list view onwards (ie. listview, edittext and button) to be a scroll view.
I know listview cannot be used inside a scrollview, but is there a way to do that ?
Any working example will be appreciated.
99% of android developers think we should not use ListView inside a ScrollView because both are scrollbale views and only parent can be scrollable, so it wraps the ListView.
Its 100% correct. But we have to use tricks to avoid this and to achieve our requirements.
I found one trick in web, which is setting the height of ListView based on the list items. Just check the link below, you will get an example code to calculate the height of ListView to fit inside a ScollView.
Android ListView height calculation to fit in ScrollView
The problem with this code is the list view will be filled entire screen if more children are available.
You have to use below template to achieve solution to your requirement.
<ScrollView >
<LinearLayout vertical>
<TextView />
<TextView />
<ListView />
<EditText />
<Button />
</LinearLayout>
</ScrollView>
I saw one video on youtube, Android ListView inside a ScrollView which is showing we can limit the height of listview, can be scrollable and used inside a ScrollView. I don't know how the programmer achieved that.
I am also thinking to produce same result by avoiding above example code. I hope it may help you temporarily. Please let me know if you got solution.
The better solution for this kind of layout is that You should use relative layout and fix ur EditText and Button at the bottom of ur screen like i have in my list view(see the image below) so that you wont need to add ScrollView in ur layout.
Just do this
<ScrollView>
<LinearLayout>
<ListView>
</LinearLayout>
</ScrollView>
Then add your
EditText
Button
Sort of a round about way to do what you want to do without a scroll view.
Write a custom adapter for your ListView
Assume you have an array of n elements that you want to populate the ListView with and then the EditText and the Button. So number of elements will be n+2
In the getView for the position n+1 return a view which has an EditText box instead of the normal list item
For the n+2 position return a Button.
Don't try to wrap around a ListView with a ScrollView, you will need up with lot of issues.
Note: I have not tested this, not even sure if it will work. Do let me know if it works. :)
I am trying to build a listview with a header row anchored to the top of the listview and scrolls with the listview. I know I'm not supposed to embed a listview within a scrollableview, but how else can I achieve this effect. I want it to look like the News Feeds screen on the stock Facebook app for Android where the "What's on your mind..." EditText scrolls away when you scroll down to read the feeds.
My pseudo-code looks like this which works but when I launch the app, it always scrolls down a bit hiding the button until I touch-scroll back up:
<ScrollView>
<LinearLayout orientation="vertical">
<Button />
<ListView />
</LinearLayout>
</ScrollView>
Rather than doing it through XML, and trying to wrap it in a ScrollView, you can use ListView's addHeaderView() method to add your custom View to the list prior to calling setAdapter().