android - best way to place objects / design an activity - android

So I received a graphic interface for an application I'm building. It has some images and texts and the images are set in a specific way, and some text goes inside or on top some images.
In the android project I opened I get the default activity which is RelativeLayout, but it's hard to set all the elements exactly where they should be with the designer and editing the XML directly seems like a pain.
I also see that elements that I add always "align" to something or right/left to some other element - but what I really want to do is place them at a specific location (so the end result will be the same as the design I got). If I was building it for the web I would have used absolute positions.
What is the correct way to go about this in android?
Thanks
EDIT
I managed to start implementing some elements of the design in a manner that makes them look ok on the eclipse Graphical Layout and on my device.
Is this XML ok - or am I using it wrong:
<ImageView
android:id="#+id/imgClouds"
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:contentDescription="#string/layout_activity_main_imgClouds"
android:scaleType="centerCrop"
android:src="#drawable/clouds_ltr" />
<ImageView
android:id="#+id/imgBaby"
android:layout_below="#+id/imgClouds"
android:layout_width="50dp"
android:layout_height="52dp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="5dp"
android:layout_marginTop="75dp"
android:contentDescription="#string/layout_activity_main_imgBaby"
android:src="#drawable/baby" />
<ImageView
android:id="#+id/imgBubble"
android:layout_toLeftOf="#+id/imgBaby"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="false"
android:layout_alignParentTop="false"
android:layout_marginLeft="56dp"
android:layout_marginTop="-5dp"
android:layout_marginRight="5dp"
android:src="#drawable/bubble_ltr" />
</RelativeLayout>

This is primarily opinion based, but there's certain things most android developers will agree, "Absolute Position" is not an option in Android, because of the OS Nature like Fragmentation in Device Screen Sizes/Densities, having an absolute position of the elements will lead to a crappy app, it will look good only in the device you are using and chances are that all the other devices will not look as you expect, you really need to look at the android design patterns and best practices to avoid a terrible GUI implementation, RelativeLayout is the best way to go, in android you must learn to love it...
Also the sooner you get used to work with XML directly in layouts will be better for you, most IDEs that help out with this functionality end up adding a lot of unnecessary code, once you go through the learning curve to build layouts using XML it totally worth it.
Hope it helps!
Regards!

Related

How to convert Android xml layout to png/svg to use in iOS version

I have an Android layout xml file here:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/locationMarker"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginBottom="30dp"
android:gravity="center"
android:orientation="vertical">
<TextView
android:id="#+id/locationMarkertext"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/rounded_corner_map"
android:gravity="center"
android:minWidth="180dp"
android:onClick="create"
android:paddingLeft="2dp"
android:paddingRight="2dp"
android:text="Pick the Location"
android:textColor="#android:color/white" />
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#android:color/transparent"
android:onClick="create"
android:src="#drawable/plus" />
</LinearLayout>
This xml layout renders to look like this:
This works fine for android but I want to use this xml layout on the iOS app as well. I was wondering if there was a way to convert this xml layout to a svg or png format or anything that would allow me to re-use this item without needing to re-create it. It needs to have transparency and a .svg would most likely be better than a .png if that works. I would like only the displayed visible part to be clickable if possible.
The equivalent technology in iOS is Apple's "autolayout" system.
It's quite easy to use once you get the hang of it; the fact is though like anything it's a specialist thing. And sure, you could just make a transparent PNG and use that as an image for a UIButton.
I would really suggest just using a "UIButton" in Apple, and play with the colors etc until you get a look that is OK -- although not identical to the other platform.
The two key points are
it's almost impossible, technically, to make apps look identical on different platforms
pretty much everyone agrees you should not try to do that; other than in games, allow elements like buttons etc. to be "natural" on each platform / os version.
BTW I have no idea why anyone would downvote your question. Cross-platform issues are one of the most critical in development today.

Android: Button change posistion when i view the app on different mobiles

I have an activity with four buttons, when i play it on the emulator everything is OK, but when i test it on my mobile the buttons grow bigger or actually the background or the screen gets smaller but the buttons stay the same, so it looks bigger.
Can i make the buttons adapt with the screen the same way the background of the activist do?
Here is my xml file
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/mainn"
android:gravity="top" >
<Button
android:id="#+id/b_labor"
android:layout_width="250dp"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="114dp"
android:background="#drawable/labb" />
<Button
android:id="#+id/b_mosul"
android:layout_width="250dp"
android:layout_height="wrap_content"
android:layout_above="#+id/b_labor"
android:layout_alignLeft="#+id/b_labor"
android:layout_marginBottom="32dp"
android:background="#drawable/ninaa" />
<Button
android:id="#+id/b_trafic"
style="#style/Theme.Transparent"
android:layout_width="250dp"
android:layout_height="wrap_content"
android:layout_above="#+id/b_mosul"
android:layout_alignLeft="#+id/b_mosul"
android:layout_marginBottom="28dp"
android:background="#drawable/traficc" />
<Button
android:id="#+id/b_nati"
android:layout_width="250dp"
android:layout_height="wrap_content"
android:layout_above="#+id/b_trafic"
android:layout_alignLeft="#+id/b_trafic"
android:layout_marginBottom="34dp"
android:background="#drawable/natiii"
/>
I think you are new to Android so you need to learn several things before creating UI elements on android devices. UI is not simple to create you should understand different concepts to create complex GUI in Android. The main problem in your above case is each device have different resolutions and if you Hard code your button then it will not adapt according to your device resolution and screen size. So before creating any UI element you need to keep some of the points in your mind:
Never try to hard code anything specially GUI parameters because these can change according to devices.
Always create and update your GUI from UIThread only.
Use asynchronous tasks, services and threads to perform heavy tasks and background tasks.
Always try to keep UI thread with minimum load.
To learn more about GUI characteristics try to explore LayoutParams for different layouts and views.
There are lot more thing you need to learn. According to me while creation of GUI you should start from Relative layouts and try not to use Absolute layout ever.
You can check below links for some help:
https://stackoverflow.com/questions/2992754/ui-design-tips-and-tutorials-for-android
http://mobile.smashingmagazine.com/2012/07/26/android-design-tips/
As we all are aware of different screen sizes of android devices , We should check for the alignment of buttons in different devices , For start check this link Developer.google
There is stackoverflow answers , that will help you
screen size vs button position

Missing or Incorrect images and backgrounds randomly throughout app lifecycle

I was hoping someone here might have an idea what causes this sort of behaviour:
Throughout my application, in seemingly random places and in random conditions I'm observing this strange UI issue. Images are on occasion being loaded black (with the correct bounds) or with the incorrect image source (again, with the correct bounds). This effects ImageViews and has effected android:background tags with references to colour resources.
My application relies on 6 library projects, it runs Native Code via a Service and Activities in the App use GlSurfaceViews (although, not all Activities which display the problem contain OpenGL components). The problem could I suppose be from any of these places or a combination of them through using large amounts of memory.
You can see this behaviour in the following screen shots:
This is actually a 6 or so pixel wide column separator image which has been incorrectly drawn into my ImageView (the ImageView seems to have correctly sized itself).
When going out of the Application and then back in again (repeatedly) it instead appeared (and remained) like so:
After a Force Clear and a Clear App Data it returned to the correct format:
As you can also see the Magnifying Glass image next to it is displaying fine in each of these. The problems with these missing/incorrect images and backgrounds seems to happen randomly, throughout the application lifecycle, and I've been unable to find a way of reproducing it.
The layouts for these images are nothing special, I'm not doing anything funny during the rendering lifecycle (i'm not overriding onDraw() or onMeasure() or the like). The source of these images aren't being set dynamically but via the XML.
As you can see from the above example, it's not a build issue as it occurs between app lifecycles not between installs. It's also happening on different devices, Samsung 8.9, Acer Iconia Tab, Motarola XOOM,
It seems to me to be some sort of error with the reference table, could it perhaps have been nudged by my native code? Or is it an effect of me in some stages of the application using too much memory?
Here's the XML source for the above example:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/browseProgressWrapper"
android:layout_width="match_parent"
android:layout_height="#dimen/actionbar_compat_height"
android:orientation="horizontal">
<RelativeLayout android:layout_width="#dimen/search_bar_width"
android:layout_height="match_parent">
<EditText android:id="#+id/browseFilter"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="4dp"
android:layout_marginLeft="5dp"
android:imeOptions="actionSearch"
android:background="#drawable/edit_text_blue"
android:maxLength="30"/>
<ImageView android:id="#+id/clearSearch"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:src="#drawable/ic_input_delete"
android:layout_marginRight="5dp"/>
</RelativeLayout>
<ImageView android:id="#+id/browseFilterButton"
android:src="#drawable/ic_menu_search"
android:scaleType="center"
android:layout_width="#dimen/actionbar_compat_height"
android:layout_height="#dimen/actionbar_compat_height"
android:layout_gravity="center_vertical"
android:minWidth="#dimen/actionbar_compat_height"/>
</LinearLayout>
A more full description of the code / layout surrounding another such occurrence I happened to get the screenshot for:
I have a "Settings" Activity which restarts my app after saving new settings details. It does this by stopping a Service, calling a new Activity (the Splash Activity) and finishing itself:
mConfiguration.save();
mConfiguration = new Configuration(Configuration.getInstance());
getActivity().stopService(new Intent(getActivity(), NativeService.class));
getActivity().finish();
startActivity(new Intent(getActivity(), SplashActivity.class));
Most of the time (and on most devices) this works fine, the Splash Activity contains an image which loads correctly. Sometimes though on some devices the Splash Activity loads either an incorrect resource (what my testers refer as "an upside down Nike tick") or just a blank box (as seen below). Does anyone know why?
Here is the Layout for the Splash page, as you can see it's pretty simple, no surprises:
<?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:background="#color/ContentBackgroundColor"
android:orientation="vertical" >
<View
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_weight="2" />
<ImageView
android:id="#+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:src="#drawable/manager_android_400" />
<View
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_weight="1" />
<ProgressBar
style="#android:style/Widget.ProgressBar.Large"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal" />
<View
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_weight="2" />
</LinearLayout>
Theory tested and debunct:
I've theorised that this could be a processor/memory issue where the Layout isn't being drawn fully before the Splash screen exits and moves onto the next Activity so I put in this piece of code:
image = (ImageView) findViewById(R.id.image);
image.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
image.getViewTreeObserver().removeGlobalOnLayoutListener(this);
moveToStartScreen.start();
}
});
The hope was the code above would make sure the Image is definitely loaded before moving onto the Start page but seems to have had no observable effect.
Another Theory
I was also wondering if this could be being caused by the R.id / R.colour / R.drawable resources some how being currupted in program execution? Does anyone know why that might happen.
Could my native code be running rampant on some memory addresses that Android isn't correctly allocating?
Has anybody noticed this before - or perhaps know why this behaviour occurs?
Graeme, I had almost the same problem and found out that it was a reported bug of the android plattform. It was corrected in the 3.0 version I think. Which API are you compiling with? Try to build with the last available api and be sure to compile with JDK 1.6
If your problem is related to this bug, this should fix the problem.
This is a simple problem of refresh, clean, and rebuild.
Images in your various drawable folders or resource id indices are out of sequence because they were either changed outside of the eclipse IDE (via external source control such as GIT, SVN or other edits) and not refreshed in the eclipse navigator. Or, the files may have been updated in a library project upon which your UI Activity depends.
I have found that although .java file dependencies are propagated throughout the system, this is not always the case for resources such as images and .xml files.
The solution is fairly simple, clean everything, refresh all of your projects, and rebuild. The stretched or black edges should be gone.
Note: The predominant manifestation of this problem occurs when 9-patch images become treated like standard .png images. This means that they get stretched in a linear manner across the image instead of just at the edges. To me, this explains your 'Torn/Stretched' example. I have seen similar often. Another common manifestation is that text strings occasionally get displayed with the wrong resources!

Android Layout Elements

I'm trying to make an Android layout like the one below. I have a couple of questions:
1 - what is the element called that FB uses for posts? Ie, it doesn't look like a text view, but the element looks like it separates each post with a divider line. Also, the text style is different for a person's name and how long ago they posted. I'm looking to duplicate this (minus pictures) but I can't find the right UI elements.
What is the element called at the bottom? It's like a static menu. IE, it's the same as a menu but instead of pressing "menu" to access it, it's on the page at all times.
Finally, are there good tutorials/examples on how to make nice looking, professional layouts like the apps on the market? The tutorials that I've found on layouts are really basic. I'd like to understand what elements exist, what all of the attributes mean and see examples, etc. So far I'm only able to see the capabilities from other applications. I'd like to have a handbook or some type of some type of reference manual to go to.
For the "fancy" text views you can make a linear layout that hosts a <RelativeLayout>:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_weight="0">
<ImageView
android:id="#+id/userPhoto"
android:layout_height="64dip"
android:layout_width="64dip"
/>
<TextView
android:id="#+id/userFullName"
android:layout_height="25dp"
android:layout_width="fill_parent"
android:layout_marginLeft="70dp"
/>
</RelativeLayout>
Once you have a relative layout you can add different views inside of that to create a sort of customeized view.
As far as good examples I would look at this book. It's easy to understand and very helpful on such things.
I found a really helpful tutorial to solve a problem in ListView Row design a bit like yours. It goes a bit further explaining how to do Async Image loading but the first part should help you.
Also, I might be wrong (I am still a bit new to this) but I think the answer above lacks a TextView for the actual message besides the userName and the relative positions of the elements since it is a relative layout. Something like:
<TextView
android:id="#+id/userName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#id/userPhoto"
android:layout_toRightOf="#id/userPhoto"
android:textSize="17dp"
android:textStyle="bold" />
<!-- actual message -->
<TextView
android:id="#+id/message"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="#id/userName"
android:layout_marginTop="1dip"
android:layout_toRightOf="#id/userPhoto"
android:textSize="15dp" />
The key in organizing a relative layout is:
android:layout_alignTop="#id/userPhoto"
android:layout_toRightOf="#id/userPhoto"
and
android:layout_below="#id/userName"
android:layout_toRightOf="#id/userPhoto"
I might be wrong but if it helps, great! Just adding my bit to the other answer.
Cheers

iOS to Android: How to display a TextView

I have a background in iPhone development, which may be a cause of some of my confusion with Android, which I am very new at developing.
My question is this: How to I create two TextViews, and specify their exact location on screen? For example, on the iPhone, I would create a UILabel, generate a rectangular frame that specified the label's size and position, and then set this rectangle to the frame property of the UILabel.
If you can help me understand the similarities with Objective C and iOS' UILabel, that would be most helpful.
On Android, we don't use absolute screen positions. This is highly discouraged. It's pretty understandable that you think this way if you are coming from iOS. But you need to revise your habits.
Instead of absolute positions, we use layouts, such as LinearLayout, RelativeLayout or FrameLayout. All of these allow you to arrange your views dynamically. And in many cases, it will automagically adapt to the screen size, which vary a lot from device to device.
Actually, there's nothing exotic about dynamic layouts. Many major UI toolkits, such as GTK, or Qt, work similarly. Pixel position are a bad idea in my opinion, except maybe in the Apple world, where the OS and the hardware are tightly coupled, but this is an exception actually.
So, in your case, all that you need is to put your text views into the appropriate layout. Please read the documentation and tutorials about the different types of layouts mentioned above to decide which one is best. The question is how you want your views to be placed relatively to each other.
Create a basic Android project in eclipse. You will be having a main.xml layout file in your project. You can open it in Eclipse using Ctrl+Shift+r and keying in main.xml
copy paste this in your xml after clearing its content.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:id="#+id/textView1"
android:layout_width="fill_parent"
android:text="TextView One"
android:layout_height="fill_parent"
android:layout_weight="1"></TextView>
<TextView
android:id="#+id/textView2"
android:layout_width="fill_parent"
android:text="TextView Two"
android:layout_height="fill_parent"
android:layout_weight="1"></TextView>
</LinearLayout>

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