I am developing a custom view & I want it displays like Google Ads view below. My view doesn't contain any text view but I still want it to have a preview like that.
Can anyone support me to a solution? Thank you!!
The "tools" namespace might be able to help you here. You can add it with a line like:
xmlns:tools="http://schemas.android.com/tools"
in your root layout. Things like tools:text will show up in the preview, but not when the app is run. So the following view:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
tools:visibility="visible"
tools:text="Preview Text" />
</RelativeLayout>
will show a TextView with "Preview Text" visible in the preview, but it is actually View.GONE and has no text when run.
Related
I made a little app with a map for learning.
Over the map I added a textView with actual position upgrading..
After some problems I did it with a such layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
android:orientation="vertical">
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:map="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MapsActivity" />
<TextView
android:id="#+id/txt_location"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:text="TextView"
android:textSize="30sp"
android:textAlignment="center"
android:textColor="#drawable/common_google_signin_btn_icon_light"/>
<ImageView
android:id="#+id/imageView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/txt_location"
android:layout_centerHorizontal="true"
app:srcCompat="#drawable/ic_action_name" />
</RelativeLayout>
Now I would add an imageView for showing gps status (focused, enabled, disabled).
I added the imageView under the textView, but I don't see anything.
After some try I'm asking why.
ps:
If I put imageVIew in a LinearLayout (before the map) I see linearLaout (in black for es.) over the map, and I still can't see image but, eventually, only the background if setted.
It's not my goal to add a linear layout, but also in this way I can't see image.
I created image by -> new image asset -> launcher icon (legacy only) clip-art (android logo) -> mo effects.
than I added it by reference in the imageView.
Solved!
I don't know if it's usual,
but adding ImageView from design window, it code Imageview as I posted.
Searching around I found similar situations and I found that correct way to show image over MapFragment is make a change to default code of ImageVIew:
from:
app:srcCompat="#drawable/img_name" />
to
android:src="#drawable/img_name" />
I don't know if I do something wrong with inserting new ImageView,
but hope this could help people that do as me.
Using Android studio 3.1, and I have a strange problem, I can't edit my UI,
I enter the content_main.xml, using the design tab, blueprint, anything i drag to the blueprint is not appearing, I use the infer constraints, still not helping
this is my XML code:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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:id="#+id/constraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context=".MainActivity"
tools:showIn="#layout/app_bar_main">
<EditText
android:id="#+id/editText5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="textPersonName"
android:text="Name"
tools:layout_editor_absoluteX="53dp"
tools:layout_editor_absoluteY="168dp" />
</android.support.constraint.ConstraintLayout>
I would't recommand using the UI designer, you don't get the feeling of what you are really doing with it. You should learn how to directly edit the XML file, this isn't really harder and at least you know what you are doing.
You must drag the widget to the component tree
ver imagen
While playing around with the Gallery I've got another question (this probably should be simpler).
I'm trying to show a view, lying in front of the Gallery, probably hiding it partially. Like a message dialog (Toast).
In order to do so, I'm using a FrameLayout with a Gallery in the back, and ImageView with a transparent src in the front. When a dialog should be shown, I'm setting the src to the needed drawable through "sendImage".
The problem is, as I assume, that the gallery/list items (that are added dynamically upon "onRequestListItem -> sendListItem") have more recent z-Order (as they have been added later), so the dialog is shown between the background of the Gallery and the transparent icons, representing the list items.
Maybe someone will have an idea, how to avoid this situation?
I am not aware of any way of adding views manually to the layout on the SmartWatch, or changing their zOrder through "bringToFront".
Here is the source code:
gallery.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Gallery
android:id="#+id/gallery"
android:layout_width="match_parent"
android:layout_height="match_parent" />
<ImageView
android:id="#+id/toast"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="#drawable/toast_dialog_message" />
</FrameLayout>
gallery_item.xml
<?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" >
<ImageView
android:id="#+id/item_icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="20px"
android:src="#drawable/item_icon" />
</RelativeLayout>
GalleryControlExtension.java
sendImage(R.id.spritz_image, drawableResourceId);
P.S. In the emulator it works as expected: toast lies over the item_icon ...
Let's imagine we are developing compound component based on LinearLayout. So, we create class like this:
public class SomeView extends LinearLayout {
public SomeView(Context context, AttributeSet attrs) {
super(context, attrs);
setOrientation(LinearLayout.VERTICAL);
View.inflate(context, R.layout.somelayout, this);
}
}
If we'll use LinearLayout as a root of somelayout.xml, we'll have extra view level, so we use merge tag:
<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some text"
android:textSize="20sp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some other text"/>
</merge>
But in Preview tab in IDE merge always acts as FrameLayout, and we'll see something like that:
(It is Android Studio, Intellij IDEA is just the same, about Eclipse I don't know)
Preview speed up developing layouts a lot, it's sad lose such a great help even for some layouts. May be there is a way to specify, how Preview should interpret merge tag in particular layout?
There is a new parentTag tools attribute (added in Android Studio 2.2) that you can use to specify the layout type for a merge tag, which will make the layout render correctly in the layout editor preview.
So using your example:
<merge xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:parentTag="LinearLayout"
tools:orientation="horizontal">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some text"
android:textSize="20sp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Some other text"/>
</merge>
Note: Both android:layout_width and android:layout_height must be specified in order for the layout to display properly in the editor.
Edit: Outdated answer. See answer by starkej2.
Android Studio 0.5.8 added support for tools:showIn. By using it it is possible to preview < merge > layouts.
http://tools.android.com/recent/androidstudio058released
layout/layout_merge.xml with tools:showIn:
<merge xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:custom="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:showIn="#layout/simple_relativelayout">
......
</merge>
layout/simple_relativelayout.xml with include:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<include layout="#layout/layout_merge"/>
</RelativeLayout>
Is also possible use custom class as parent instead of merge like
<com.mycompany.SomeView xmlns:android="http://schemas.android.com/apk/res/android">
...
</com.mycompany.SomeView>
And then directly inflate this layout and cast result view to SomeView.
Android studio will directly check parent class of SomeView and handle preview like LinerLayout.
You can use onFinishInflate() method in the SomeView to bind views by findViewById().
Benefit of this solution is that you can put all layout definitions or style definition directly to the layout file, you can't use method like setOrientation() in code.
I extended AutoCompleteTextView in android. When I use that new custom AutoCompleteTextView in my XML layout file, Eclipse shows an error saying:
You must specify a valid content view by calling setContentView() before attempting to show the popup. Exception details are logged in Window > Show View > Error Log"`.
Edited XML File is:
<?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:orientation="vertical" >
<com.mypackage.MyAutoCompleteTextView
android:id="#+id/countries_list_custom"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:completionHint="Test">
<requestFocus />
</com.mypackage.MyAutoCompleteTextView>
<TextView android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
By simply taking out my custom view from the XML, the layout shows just fine.
Any help will be greatly appreciated, thanks.