Android Studio: Accidentally ignored "xmlns" attribute - android-studio

Using Android Studio in the XML-Layout-editor,
When an error saying something about the xmlns not being found, I checked quickly for a fix with the help of the editor, and I chose one that said something about ignore.
Suddenly, this error,
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
....
</RelativeLayout>
Where it says element RelativeLayout must be declared and this follows for all childrens aswell.
The <RelativeLayout is the part that has the error. Also the childern, such as <LinearLayout has this error.
Where can I remove the ignore?

You can check if the file is in "layout" folder.
I also met the error element RelativeLayout must be declared. I realized that my file was located in "drawable" folder, instead of the "layout" folder. That's why the error showed up.

Related

EditText with hint, where hint moves

I have seen EditText that has a hint and when user taps on it the hint moves up reducing the font size and making the field editable by the user. When the user moves to another EditText leaving it blank the hint appears back in full size.
What is it and how can I add it in my activity on Android Studio using XML?
I am on Android Studio using Kotlin.
if you mean this
it is TextInputLayout
Add the dependency for the design support library inside the build.gradle (Module: app) file as shown below.
implementation 'com.google.android.material:material:<version>'
the latest version at this time is 1.2.0-alpha03 you can see latest version from mvnrepository
Then, you can use it like this in your xml layouts.
<com.google.android.material.textfield.TextInputLayout
android:id="#+id/myTextInputLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.google.android.material.textfield.TextInputEditText
android:id="#+id/my_editText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="#string/YOUR_HINT"
android:singleLine="true"
android:textColor="#color/colorDarkestGray" />
</com.google.android.material.textfield.TextInputLayout>
This is TextInputLayout and you can use editText as child in it like this :
At first add the dependency for the design support library inside the build.gradle file as shown below.
implementation 'com.android.support:design:25.3.1'
And if you are using AndroidX use this :
implementation 'com.google.android.material:material:1.0.0'
Second ,Then implement that like this :
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="#dimen/activity_horizontal_margin">
<android.support.design.widget.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Floating Hint Enabled Default" />
</android.support.design.widget.TextInputLayout>
Android TextInputLayout Features
1-Enabling/Disabling floating hints
2-Enabling/Disabling floating hint animation
3-Displaying Error Messages
4-Showing Character Counter
5-Password Visibility Toggle and . . .

i cant add button to linear layout

I have a listActivity that displays via an adapter an xml feed fetched from the web, adn the layout file activity_list_feed.xml :
`<ListView
android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:drawSelectorOnTop="false"
android:transcriptMode="normal"
/>`
In the graphic editor i cannot drag a button into this layout, and when i try to hardcode as per this file :
`<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<Button
android:id="#+id/addBtn"
android:text="Add New Item"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:onClick="addItems"/>
<ListView
android:id="#android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:drawSelectorOnTop="false"
android:transcriptMode="normal"
/>
</LinearLayout>`
i get a compile error message :
java.lang.ClassCastException: android.widget.LinearLayout cannot be cast to android.widget.TextView
How can i add a button on top of the list because i want to refresh the pull.thank you.
The code that you provided actually works in its current state in Android Studio:
Make sure that in your java code, you are referencing the correct item. Make sure that you're setting the overall layout to be that layout, and THEN doing findViewById(R.layout.addBtn).
Also, try changing the Android Version in your IDE to 22 (as I have it set in the top right corner of the picture). That may solve your error.
I managed to add the button in the editor and this without setting to API 22 as per your picture. However the program didn't compile still.
The message error "ArrayAdapter requires the resource ID to be a TextView" meant i didn't provide the right argument to the adapter.
According to this answer :
"ArrayAdapter requires the resource ID to be a TextView" xml problems
it appears that the choice of the constructor is important, since i wanted to add a button in the view, i must use the constructor with 4 arguments (the additional argument being the id of the view):
http://developer.android.com/reference/android/widget/ArrayAdapter.html#ArrayAdapter(android.content.Context,int,int,java.util.List)
Using this constructor solved the problem.

android, xmlns, No resource indentifier error

In an xml layout file, the xmlns is already defined, but I get this error at compile time: No resource identifier found for attribute. Why is that? thanks
I'm following a Facebook dev tutorial on facebook site https://developers.facebook.com/docs/getting-started/facebook-sdk-for-android/3.0/ the layout file is as follows:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<com.facebook.widget.ProfilePictureView
android:id="#+id/profilepic"
android:layout_height="wrap_content"
android:layout_width="0dp"
android:layout_weight="1"
app:preset_size="large" app:is_cropped="true"
/>
</ScrollView>
I figured it out, have to replace /res-auto with res/com.facebook.samples.profilepicture
Your layout file looks correct. check that in your 'project.properties' file, the 'android.library.reference.1' value points to the correct location.
The res-auto is feature properly supported in API level 17. It must be applied for all layouts using custom attributes. It is automatically replaced on build time, by eclipse.
Ref Updated SDK Tools and ADT revision 17

Full screen Android phone app doesn't show full screen on Google TV

The following simple layout shows full screen on an Android phone, but not on Google TV where it
it shows on only a part of the TV screen (top half and middle third) and there's some sort of wallpaper on the rest of it (just saying in case it's not that usual, documentation is rare as far as I could see).
<?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">
<com.orb.androidplayer.view.VideoSurfaceView
android:id="#+id/video_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>
The problem isn't coming fom the video widget either, it's the
same if I remove it, add a TextView instead, try fill/match parent, etc...
Can anyone assist me with identifying the cause of the issue?
Try setting your application or activity theme to
android:theme="#android:style/Theme.Holo.NoActionBar.Fullscreen"
Try add element min SDK in AndroidManifest.xml
Exp: <uses-sdk android:minSdkVersion="7" />
Remove the <supports-screens/> tag from the AndroidManifest.

How to use a ShapeDrawable with an xml layout resource

I would like to be able to define a ShapeDrawable in my layout file and then inflate that so I can draw on it.
I have followed the tutorial on the android developers' site but I cannot see how I reference my ShapeDrawable in my main class file.
How do I actually inflate it?
I have put the following the following into my layout file:
<com.example.shapedrawable.CustomDrawableView
android:id="#+id/customDrawableView"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
Once you have defined the ShapeDrawable in its own XML file, you need to add the following to the layout.xml where you want it to be included:
<ImageView
android:src="#drawable/shapeDrawable_filename"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
If you want to do it programmatically, I don't have an answer (yet), but from your question, it seems this should work!
Let me know if that helps ;)

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