Develop Reference

Card view not working below Lollipop version

I am using card view but the elevation and card view properties are not working below version 5.0.
I tried to use card_view:cardUseCompatPadding="true" by searching some SO posts but this also did not work.
It should look like this
And it looks like this on 4.2.2
Here is layout:
<android.support.v7.widget.CardView
xmlns:app="http://schemas.android.com/tools"
android:id="#+id/card_view"
app:cardUseCompatPadding="true"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="05dp"
android:layout_marginTop="05dp"
card_view:cardElevation="12dp">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="60dp"
android:background="#color/bg">
<View
android:layout_width="3dp"
android:layout_height="match_parent"
android:background="#color/cardLineColor"></View>
<LinearLayout
android:id="#+id/linearLayout6"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_marginEnd="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:layout_marginStart="10dp"
android:orientation="vertical">
<TextView
android:id="#+id/txt_id"
android:layout_width="103dp"
android:layout_height="wrap_content"
android:text="ID"
android:textColor="#color/white" />
<TextView
android:id="#+id/txt_date"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="05dp"
android:text="23/3/2015"
android:textColor="#color/textColor"
android:textSize="10sp" />
</LinearLayout>
<TextView
android:id="#+id/txt_trans_type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/linearLayout6"
android:layout_centerHorizontal="true"
android:text="sent money"
android:textColor="#color/white"
android:textStyle="bold" />
<LinearLayout
android:id="#+id/linearLayout8"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_alignTop="#+id/linearLayout6"
android:layout_marginEnd="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:layout_marginStart="10dp"
android:layout_toEndOf="#+id/txt_trans_type"
android:layout_toRightOf="#+id/txt_trans_type"
android:orientation="vertical">
<TextView
android:id="#+id/txt_balance"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="end"
android:text="$3214"
android:textAlignment="viewEnd"
android:textColor="#color/white"
android:textStyle="bold" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="end"
android:layout_marginTop="05dp"
android:text="#string/balance"
android:textAlignment="viewEnd"
android:textColor="#color/white"
android:textSize="10sp" />
</LinearLayout>
</RelativeLayout>
</android.support.v7.widget.CardView>
Edit: I created 9 patch file like this
But this is giving this error:
Error:Some file crunching failed, see logs for details
Error:Execution failed for task ':app:mergeDebugResources'.
> Error: Some file crunching failed, see logs for details
May be its height width is much? I tried with small height width but then it leaves some gap. How can I match it to all devices?

Use app:cardElevation="12dp"
instead of card_view:cardElevation="12dp"
Hope it helps.

Sadly, elevation, as you mentioned it, is not available for API 19 and below.
The solution I chose for my similar issue is to replace my cardviews by regular layouts and use 9-patch images as background to generate the shadows. It has the advantage to be very modulable, plus, unlike the elevation property, you can have more customization like shadow colors if you don't want a simple black shadow.
The only problem is that you have to design the image yourself and add it to the project. But fear not, there is some handy generators like this one that can generate it for you. Just make sure that you set a minimum size that is less than your layout to be sure it fits without deforming it. I usually generates a 10*10 pixels wide image, and shadows won't be deformed even when applied to a much larger view.
When you got your image (name should look like myimage.9.png), you simply add it to your drawables, without removing the .9.png extension, and then set it as a regular background drawable to your layout, via xml or code. And you're done !
EDIT : Did not notice you also have lighting on the top of the cardview.. What you can try if you have something like Photoshop, is to create yourself the 9-patch, by applying drop shadows for the dark one, then creating a second layer to add another drop shadow but this time set to white and with the appropriate angle to display it above. Then you save it as png and use the 9-patch generator to convert it to a .9.png image.
See the 9-patch documentation here. If you're using Android Studio, there is also a built-in generator for 9-patches.
Sadly, user interface was kinda limited for advanced displaying like shadows before Material Design stepped in with Android 5. Maybe you can add your cardviews programmatically, so you can do something like this
if (android.os.Build.VERSION.SDK_INT <= android.os.Build.VERSION_CODES.LOLLIPOP){
//Add regular layout to your views with 9 patch
} else{
//Add cardview to get desired effect
}
That way most of your users will have your desired cardviews, but it can quickly increase the amount of code you'll need if you need your element to be clickable/draggable/etc.

Custom looking searchView android

I need to create a custom looking SearchView that opens when an ImageButton, that I already have in my MainActivity.xml, is pressed.
I would really appreciate if you could explain me how to do it, because all I could find on SO was either people not having a custom looking SearchView or having it permanently on their TitleBar which I do not have since I'm using the light.NoTitleBar theme.
This is what I would need it to look like, this is a design I made with photoshop:

You have mutliple ways to obtain what you are looking for in term of design.
A solution i use (wich may not be the best) is to put my EditText (your search field) in a FrameLayout, this way i can have a search button and delete text button overlapping my textView:
XML Example :
<FrameLayout
android:id="#+id/SearchTextInputLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center"
android:minWidth="100.0dp">
<EditText
android:id="#+id/SearchTextInput"
android:textColorHint="#layout/inputselector"
android:hint="Search terms here..."
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<Button
android:id="#+id/ClearSearchButton"
android:layout_width="25dp"
android:layout_height="25dp"
android:layout_marginEnd="10dp"
android:layout_marginRight="10dp"
android:layout_gravity="end|center_vertical"
android:background="#android:drawable/ic_delete" />
</FrameLayout>

Image view doesn't display image if screen is not rotated and an other image view has been updated

Issue
I've got an issue with 2 ImageViews on Android.
The first displays a large image. It is inside a RelativeLayout, and is a custom ImageView (com.ortiz.touch). It was displaying well until now.
The second is also inside the RelativeLayout but is a "normal" ImageView. It shows bluetooth state. Displaying it doesn't cause any issue.
However, when I put code that changes the src of the bluetooth indicator programatically, the first image is not displayed anymore ....
Is the problem coming from the custom view not doing its job right ? Am I missing something ?
Code
If I'm not doing this kind of stuff :
bluetoothState.setImageResource(R.drawable.bluetooth_enabled192);
The image is displayed correctly.
Here's the layout I use :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#1b1b1b"
android:theme="#style/Theme.AppCompat.Light.NoActionBar.FullScreen">
<com.ortiz.touch.TouchImageView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/imageView"
android:layout_gravity="center"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_above="#+id/textView" />
<TextView
android:layout_width="fill_parent"
android:layout_height="32dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/emptyDisplayText"
android:layout_gravity="center_horizontal|bottom"
android:gravity="center_vertical|center_horizontal"
android:textAllCaps="true"
android:elegantTextHeight="false"
android:ellipsize="end"
android:maxLines="1"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:textSize="15sp"
android:textColor="#f3f3f3"
android:id="#+id/textView"
android:background="#drawable/rounded_rect"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentBottom="true"
android:layout_margin="10dp" />
<ImageView
android:layout_width="52dp"
android:layout_height="52dp"
android:id="#+id/bluetooth_state"
android:scaleType="centerCrop"
android:layout_alignParentTop="true"
android:layout_alignRight="#+id/textView"
android:layout_alignEnd="#+id/textView"
android:layout_gravity="top|right"
android:layout_margin="10dp"/>
</RelativeLayout>
Desired Result
What I get is the same screen without the central image (the text and bluetooth indication are displayed correctly)
 NB
I'm starting to get quite depressed on that issue. I just want to display 2 images. Thank you.
Edit
I've not mentioned it, but the main image is loaded in background, using an AsyncTask. I've tried to add some View.invalidate() (on top level layout, on image, on bluetooth indication) but it hasn't solved the problem.
In addition to the image appearing on rotation, it also appears when I try to pinch the non-existant image. And trying to reset the zoom (hacky) programatically doesn't work either.

Okay I've found the error.
As I said, I have a AsyncTask (BitmapWorkerTask) that I call to load a Bitmap into an ImageView in background.
It's called like this :
new BitmapWorkerTask(imageView, getApplicationContext()).execute(filename);
Changing getApplicationContext() to MainActivity.this or getContext() solves the issue :/ (However, I still find it's quite magic how it worked fine for so long even if application context != activity context !)

Eclipse not displaying TextView

Okay, so the thing is that I'm trying to display text but it won't let me. the code is :
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/app_name"
android:textAlignment="center"
android:textColor="#000000"
android:textColorLink="#android:color/black"
android:textStyle="normal" />
What have I done wrong? (the text won't appear on screen)

At your string resources app_name might be empty or null.
There is another view that prevents your TextView to be displayed at your screen, take a look at your layout file.
The value for TextView modified to a null/empty value in your code.

Try this
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:gravity="center"
android:text="Flights"
android:textColor="#android:color/white" />

Your code is correct as it is working for me. The probable mistake you have done is that your String resource variable "app_name" is empty or you can provide the full xml code for us to have a better look at this problem.

Problem with basic Android xml GUI

I've just started working on a basic Android GUI using XML - when I run it, logcat tells me "Binary XML file line #16: You must supply a layout_width attribute."
When I try and the program, it throws the error "The application HelloAndroid has stopped unexpectedly.
Its the basic hello Android code -
UPDATE - Got it so far! Thanks for the help! :)

There is a part in your layout:
<TextView
android:text="#string/main_title"/>
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center">
android:marginBuottom="20dip"
android:textSize="24.5sp" />
As you can already see from the code highlighting here, some parts of this element are black. Thats because you closed this TextView via /> on the second line. All the other parameters are not belonging to this element anymore. Therefore the parser can't find layout_width, layout_height and so on - and complains about this ("you didnt specify ..."). Remove the /> on the top and you should be fine.
Edit: The correct version should look like this:
<TextView
android:text="#string/main_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:marginBottom="20dip"
android:textSize="24.5sp" />
or alternatively (since this here is the shorthand version
<TextView
android:text="#string/main_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:marginBottom="20dip"
android:textSize="24.5sp"> </TextView>

This view looks OK. But check your landscape xml. There's an issue with layout_width property in the xml - it's missing or maybe there's some typing mistakes (usually android:layout_width replaced with android.layout_width).
android:layout_width and android:layout_height properties are required for every control you add to the xml.
EDIT:
<TextView
android:text="#string/main_title"/>
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center">
android:marginBuottom="20dip"
android:textSize="24.5sp" />
You are ending your TextView element after the android:text property - android:text="#string/main_title"/>. Remove />
EDIT:
Also you have an typing mistake in android:marginBuottom="20dip". This line should be a android:layout_marginBottom="20dip".