Database Users

[Q] ScrollView, SetText and scrollTo

Hi,
Im just getting into Android development and picking up pace slowly. Getting confused how people are getting settings style menus with the appropriate colour Summary Line while adding icons for Stars and Checkboxes etc to highlight and tick.
Anyhoo, I have a TextViews inside a LinearLayout inside a ScrollView, seems to work OK. I use SetText to set the Text on the TextViews and I create everything at run time instead of through the XML files.
But the application I have is a polling type application and I need to repopulate the TextViews and redraw the ScrollView in the same position that the user scrolled to previously.
Im accutely aware of problems using ScrollTo after you've used SetText, so I found the following code:
Code:
sView.post(new Runnable() {
public void run() {
sView.scrollTo(0, iTop);
}
});
It works, but there's a screen flicker where it first draws the screen in its normal position then sets the scrollTo.
What is the best way of achieving this, or am I doing everything completely backwards and most normal people wouldn't have this kind of problem?
Thanks
Simon

It sounds more like you might want to consider using a listview instead. It was designed to contain several child views and scrolls and updates seamlessly.

Hi,
Thanks for the reply. Perhaps I am a bit too much of a beginner.
I seem to be favouring TableLayout so that I can display tabular data and have columns resize correctly and have the data presented OK.
I think that's why I went with updating everything at design time because I have a variable number of rows that can be added. IIUC, variable rows (in an XML file) I think can only be created using ListView, but of course a TableRow needs a TableLayout as a parent.
Here is the idea...
Code:
<?xml version="1.0" encoding="utf-8"?>
<TableLayout android:id="@+id/TableLayout01" android:layout_width="fill_parent" android:layout_height="fill_parent" xmlns:android="http://schemas.android.com/apk/res/android"><TableRow android:id="@+id/TableRow01" android:layout_width="wrap_content" android:layout_height="wrap_content">
<TextView android:text="@+id/TextView01" android:paddingRight="5px" android:id="@+id/TextView01" android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView>
<TextView android:text="@+id/TextView02" android:id="@+id/TextView02" android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView>
</TableRow>
</TableLayout>
The code I have for TableRows is not dissimilar to, http://en.androidwiki.com/wiki/Dynamically_adding_rows_to_TableLayout
But of course using setText means I cannot then scrollTo

Duh.
First learning curve mastered.
You only need to add views to containers etc the first time you display the screen.
You can update the text in the views later on without affecting the screen position.
I like this.

[Q] addind a button to a secondary view is crashing my program

I am making a game that has a main.xml view (the default one that the game screen is made from. But I have a button for "help" that starts a new view which is just text explaining how to play the game. But I want to add a button to the help menu that will take the user back to the main game. Only problem is when I add a button to the xml file for it, it always crashes as soon as it is called. All the other buttons work fine in main.xml but I cant get the ones in the help.xml to work. Any suggestions?

The way that android's view hierarchy works is actually kind of complicated, and is one thing that I still at times struggle to grasp.
So when you press the help button, and help.xml is supposed to show up, it crashes?

yeah, heres my xml code:
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
androidadding="10dip" >
<TextView
android:id="@+id/about_content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Text goes here" />
</ScrollView>
But it crashes if theres a button inside of it

are you using the new layout in the same Activity or a new one? If the same, try out making a new Activity class (remember to add it to manifest!), it might be a lot easier to then determine your problem if it's separate.
We could do with a logcat output of the crash to help determine what's wrong

Two simple Android SDK things I need help with

I actually yesterday spent some more time with Eclipse Android SDK yesterday and learned how to: center buttons, add buttons, add admob, etc. but I still need to know 2 things:
How do I put buttons side to side?
How do I add sounds to buttons?
P.S. - I am not sure if this is the correct place to post this. I was just spending lots of time trying to the above things out and couldn't, so I figured why not ask the developers pros here at Xda.

I prefer to use RelativeLayouts instead of LinearLayouts.. I feel that LinearLayouts are much more difficult to work with, and are much less intuitive.
When using a RelativeLayout, you could do something like this:
<Button android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@+id/button2"
/>
<Button android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
This would put button1 to the right of button2.
Additionally, if you wanted some space between them, you could specify this in button1:
android:layout_marginLeft="10dp"
To add sounds to a button click... explore the MediaPlayer class.
In the onClickListener of your button, you would have something like media.start()

[Q] layout help

I just started to build my app's layout and I'm confused, so I could use a little help.
I want it to look like this:
- there's a bar with buttons which always stays on the bottom of the screen (like position:fixed in CSS)
- there are two (or more) lists with a dynamic number of records which will mos definitely overgrow the screen size, so I need a scrollbar on them. These will not push down the button bar.
This is easy as hell, I know, but I'm not sure how to do it properly so I won't need to change it later.

It's all about learning to love (and hate) RelativeLayout
http://blog.maxaller.name/2010/05/attaching-a-sticky-headerfooter-to-an-android-listview/

Yeah, should just be a ScrollView with a nested RelativeLayout putting your buttons on the bottom...not too painful

I have a problem with my ListView. I want it to be full size without a scrollbar (the parent of ListView is scrollable), but it shows up really short (only 1.5 rows fit in). Here's my code :
Code:
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_below="@id/top_controlbar"
android:layout_above="@id/bottom_controlbar">
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<!-- GEOTASKS -->
<LinearLayout
android:id="@+id/geotasks_layout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginTop="10dp"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="30dp"
android:text="@string/main_header_geotask"
android:textSize="18sp"
android:background="@color/header_bg"
android:textColor="@color/header_text"
android:gravity="center"
android:layout_marginBottom="5dp"
/>
<ListView
android:id="@+id/list_geotasks"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
<TextView
android:id="@+id/empty_geo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/main_empty_geo"
android:textSize="15sp"
android:paddingLeft="5sp"
/>
</LinearLayout>
etc, same for timed and simple tasks
I tried changing the height of the parent layout and the listLayout (all 4 combinations), but it didn't help.

Well **** my rusty sheriff's badge. I can't believe nobody knows the answer.

ScrollViews are weird. The way they stretch to fill content is not intuitive.
I can't remember the solution off the top of my head but do some googling for "ScrollView" and I think there are some answers on stackoverflow.
hth

My problem is not the scroll view, but ListView. Scrollview stretches without problems.
I want to achieve a simple thing - make the ListView display all of it's content without scrolling. How is that not possible ? OMG
At first I used LinearLayouts and added new views to the root layout. That was very ugly and I couldn't register those views for context menus. Then I found out about list views, and I couldn't be happier if I could just do this one thing.

Sorry I misunderstood what you were asking.
What's the point of having the parent of a ListView scrollable anyways? I think you're just thinking about things in a strange way and that what has got you stuck.
ListView has an addHeaderView() addFooterView() if you need static items at the top and bottom, and you know how to put bottom and top control bars using relative layout, why not eliminate the ScrollView?
I think you're making things difficult on yourself by putting something scrollable inside something scrollable.
Your other option is to use views like you were using them, they do support context menus: http://developer.android.com/reference/android/view/View.OnCreateContextMenuListener.html
Hope that helps.
Edit: btw, the reason I am recommending it this way is that even if you override ListView's onTouchEvent, I dont think it will expand to wrap all the content and be scrollable by the ScrollView. Instead it will just sit there as an unscrollable listview that leaves the user unable to reach the content beyond what they can see originally.

Noob layout issue - probably VERY EASY!!

I'm essentially trying to create a MadLibs app for my kids. I'll type in the text of the books they already have and they can play with it in the car. But I'm a noob and I haven't done much else other than the first few simple apps in tutorials - my brain got tired trying to figure out sqlite stuff, so this all went on the backburner and now here I am again giving it another effort.
So I was thinking something ridiculously simple, like just having a textview string of the first part of a sentence, then an edittext with a hint set for the type of word to fill in, followed by the rest of the sentence in another textview string. Lather, rinse, repeat. Easy, right?
I can't seem to figure out how to get the objects to flow properly in the layout... First problem is that the edittext is gigantic compared to the textview. I could probably figure that one out easy enough, but my second problem prevents me from actually seeing the effects of my changes, and that problem is that the text doesn't flow onto the next line.
I've tried linearlayout and relativelayout, but I'm turning here for some guidance before I waste countless hours. Should I just build each paragraph (textview) as a single string comprised of other strings and edittext variables?
Any help would be great appreciated. And remember: go easy on me.
Here's my current activity_main.xml:
Code:
<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: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=".MainActivity"
android:orientation="horizontal">
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/textBody01"
android:weight="1" />
<EditText
android:id="@+id/editText1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:hint="@string/hint_adjective"
android:weight="1" >
<requestFocus />
</EditText>
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/textBody02"
android:weight="1"/>
</LinearLayout>

etnpnys said:
I'm essentially trying to create a MadLibs app for my kids. I'll type in the text of the books they already have and they can play with it in the car. But I'm a noob and I haven't done much else other than the first few simple apps in tutorials - my brain got tired trying to figure out sqlite stuff, so this all went on the backburner and now here I am again giving it another effort.
Click to expand...
Click to collapse
Could you post a quick picture (just a rough one in paint or something) showing the desired layout ?

Absolutely. I'll mock one up and get it on here shortly.
Sent from my SPH-L710 using Tapatalk

PicomatStudios said:
Could you post a quick picture (just a rough one in paint or something) showing the desired layout ?
Click to expand...
Click to collapse
Here's a little bit of how I'm thinking this should work out pretty easily. In the end, I would like to have the filled-in words in bold red text and the rest of the body paragraphs as regular black text, and I would like to make the background black to hide the body of text. I would then have a button that calls a function to change the background to white to make the body text visible "onclick" -- or maybe toggle between black/white/whatever.
The first hurdle is right here with the layout. I mean, this is REALLY simple, right?
View attachment 2380717

etnpnys said:
Here's a little bit of how I'm thinking this should work out pretty easily. In the end, I would like to have the filled-in words in bold red text and the rest of the body paragraphs as regular black text, and I would like to make the background black to hide the body of text. I would then have a button that calls a function to change the background to white to make the body text visible "onclick" -- or maybe toggle between black/white/whatever.
The first hurdle is right here with the layout. I mean, this is REALLY simple, right?
View attachment 2380717
Click to expand...
Click to collapse
Maybe not that simple
As I understand it you want the text to flow continuously left-to-right, top-to-bottom, a bit like floating CSS layouts ?
That is you might want it to do...
Mary had a [edit text] lamb. Its
fleece was white as snow.
Where that's 2 TextViews with an EditText between them ?
You will struggle to do that on Android, since there is not built in concept of 'flow' as you may be imagining.
The closest you will get is a RelativeLayout but you'll have to work hard to line the views up correctly.
You could try something like this, or maybe this. The second one links here where there is somebody's FlowLayout code towards the end of the page. I haven't tried it but it looks close to what you need at first glance. The concept appears to be a ViewGroup which calculates where its children should be and positions them accordingly.

You get my ideas exactly. I'll look into those! Much appreciated!
Sent from my SPH-L710 using Tapatalk

Just to button this up, I wanted to chime in to let everybody know which direction I went.
Basically, I have a vertical linear layout comprised of:
several editText fields for user input. @hint points to strings that indicate what kind of word (noun, adjective, etc) needs to be filled in.
a "Create" button
a "Clear" button
a textView
Behind the scenes, I set a series of "sentenceFragment" variables that contain the body text. Those all end with a "[" and start with a "]" so that the filled-in words can be easily seen once the story is built. Users fill in the editText fields and click the "Create" button. When clicked, I used getText on each of the editTexts to store each as a string, then a "paragraph" variable is built from concatenating all of the sentenceFragments + editTexts, then I used setText to the textView to display the entire story below.
The "Clear" button then uses setText on the textView and the editTexts to blank them out.
So, in the end, the user is presented with stuff like:
Sometimes you just want to get a [green] car. In your search, you find several [bugs] on the seat.
Thanx for you help, everybody! Now I'm looking into putting a spinner at the top to let the user select different stories... Anybody wanna point me in the right direction there?