I want a RelativeLayout based android UI that looks like the below mock graphic:
Below is my layout xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/RelativeLayoutForPreview"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<!-- surface view that contains camera preview , and seats above #+id/linearLayoutToolbar -->
<SurfaceView
android:id="#+id/surfaceViewBarcodeScanner"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<!-- LinearLayout that contains toolbar that is divided into 3 sections horizontally -->
<LinearLayout
android:id="#+id/linearLayoutToolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/surfaceViewBarcodeScanner"
android:orientation="horizontal" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/scanner_bottom_left" />
<ImageView
android:id="#+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/scanner_bottom_center_toolbar" />
<ImageView
android:id="#+id/imageView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/scanner_bottom_right_landscape_button" />
</LinearLayout>
</RelativeLayout>
I used Eclipse GUI palette and my own editing , however the output was not what I expected, the SurfaceView seems to covering all the screen, the LinearLayout at the bottom does not appear.
Snapshot of my current result on Galaxy S3 device:
Any help will be appreciated, Thanks.
Could you please try out to modify your layout as the follows:
Define your SurfaceView and set it's layout_above value to the ID of the linear layout made in the previous step. Set the layout_alignParentTop to true.
Define your bottom linear layout and set the layout_alignParentBottom to true.
Smart code snippet with only the important parts:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android">
<SurfaceView
android:id="#+id/surfaceViewBarcodeScanner"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_above="#+id/linearLayoutToolbar" />
<LinearLayout
android:id="#+id/linearLayoutToolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true" />
</RelativeLayout>
I hope this will solve your problem.
you can use Linearlayout instead of Realtive Layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<SurfaceView
android:id="#+id/surfaceViewBarcodeScanner"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1" />
<LinearLayout
android:id="#+id/linearLayoutToolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<!-- inside elements -->
</LinearLayout>
</LinearLayout>
else you should use android:layout_above="#+id/linearLayoutToolbar" to your surfaceview
and remove android:layout_below attribute and add android:layout_alignParentBottom="true" to your toolbar view.
// try this
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/LinearLayoutForPreview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="5dp"
android:orientation="vertical">
<LinearLayout
android:layout_height="0dp"
android:layout_weight="1"
android:layout_width="match_parent">
<SurfaceView
android:id="#+id/surfaceViewBarcodeScanner"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
<LinearLayout
android:id="#+id/linearLayoutToolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="0dp"
android:gravity="center"
android:layout_weight="1">
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/scanner_bottom_left" />
</LinearLayout>
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="0dp"
android:gravity="center"
android:layout_weight="2">
<ImageView
android:id="#+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/scanner_bottom_center_toolbar" />
</LinearLayout>
<LinearLayout
android:layout_height="wrap_content"
android:layout_width="0dp"
android:gravity="center"
android:layout_weight="1">
<ImageView
android:id="#+id/imageView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/scanner_bottom_right_landscape_button" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
Related
Dear Android Developers I am a creating cv Android app but there are empty after TextView inside CardView how can I get rid of that space
below my xml code where I have implemented CardView as parent child as LinearLayout.
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
card_view:cardCornerRadius="0dp"
card_view:cardPreventCornerOverlap="true"
card_view:cardUseCompatPadding="true">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ImageView
android:id="#+id/imageView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="30dp"
android:scaleType="centerCrop" />
<Space
android:layout_width="50dp"
android:layout_height="20dp" />
<TextView
android:id="#+id/about"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginRight="250dp"
android:gravity="center"
android:text="#string/about_me"
android:textSize="16sp"
android:textStyle="bold" />
<TextView
android:id="#+id/introduction"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="16dp"
android:gravity="start" />
</LinearLayout>
</android.support.v7.widget.CardView>
Change layout height of card view to match_parent
reduce marginTop of your text View remove the Space tag also and also reduce margin of your imageView
use this attributes in your cardview you can see the difference
your card do not have elevation and radius and that card view merge to the activity that's why it showing like a space after text use this in your card view:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="8dp">
<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
card_view:cardCornerRadius="8dp"
card_view:cardElevation="6dp"
android:elevation="4dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:orientation = "vertical">
<ImageView
android:id="#+id/imageView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="30dp"
android:scaleType="centerCrop" />
<TextView
android:id="#+id/about"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginRight="250dp"
android:gravity="center"
android:text="#string/about_me"
android:textSize="16sp"
android:textStyle="bold" />
<TextView
android:id="#+id/introduction"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="16dp"
android:gravity="start" />
</LinearLayout>
</android.support.v7.widget.CardView>
</RelativeLayout>
How to add Floating Action Button from the support library for CardView so that when you scroll through the ScrollView, the button has gone up along with the card?
My app
before scrolling
after scrolling
The button should go along with the card
I want to fix this
Layout
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
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:fitsSystemWindows="true"
>
<ScrollView
android:id="#+id/nested_scroll_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/white_vk_background_color">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/spacing_8"
android:orientation="vertical"
android:padding="#dimen/spacing_16">
<android.support.v7.widget.CardView
android:id="#+id/behavior_card_view"
style="#style/RateCardView"
app:cardBackgroundColor="#color/white"
app:cardCornerRadius="#dimen/spacing_2"
app:cardElevation="#dimen/spacing_8">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="#dimen/spacing_16"
android:orientation="vertical"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:paddingBottom="#dimen/spacing_8">
<TextView
android:id="#+id/description_rate_usd_text_view"
style="#style/AppTextView.RateTextView"
android:text="#string/description_currency_text_view_usd"/>
<TextView
android:id="#+id/rate_usd_text_view"
style="#style/AppTextView.RateTextView"
android:layout_centerHorizontal="true"
android:layout_toRightOf="#id/description_rate_usd_text_view"
tools:text="63.99"
/>
<TextView
android:id="#+id/rate_difference_usd_text_view"
style="#style/AppTextView.DifferenceTextView"
android:layout_toRightOf="#id/rate_usd_text_view"
tools:text="+0.44"/>
</RelativeLayout>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:paddingBottom="#dimen/spacing_8">
<TextView
android:id="#+id/description_rate_eur_text_view"
style="#style/AppTextView.RateTextView"
android:text="#string/description_currency_text_view_eur"/>
<TextView
android:id="#+id/rate_eur_text_view"
style="#style/AppTextView.RateTextView"
android:layout_centerHorizontal="true"
android:layout_toRightOf="#id/description_rate_eur_text_view"
tools:text="71.99"
/>
<TextView
android:id="#+id/rate_difference_eur_text_view"
style="#style/AppTextView.DifferenceTextView"
android:layout_toRightOf="#id/rate_eur_text_view"
tools:text="+0.15"/>
</RelativeLayout>
<TextView
android:id="#+id/rate_update_time_text_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom|start"
android:layout_marginBottom="#dimen/spacing_8"
android:layout_marginLeft="#dimen/spacing_16"
android:layout_marginTop="#dimen/spacing_16"
android:gravity="center"
android:textSize="#dimen/density_font_size_text_date"
tools:text="Date: 15.07.2016"
/>
</LinearLayout>
</android.support.v7.widget.CardView>
<android.support.v7.widget.CardView
android:id="#+id/converter_card_view"
style="#style/RateCardView"
app:cardBackgroundColor="#color/white"
app:cardCornerRadius="#dimen/spacing_2"
app:cardElevation="#dimen/spacing_8">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="#dimen/spacing_16">
<com.rengwuxian.materialedittext.MaterialEditText
android:id="#+id/converter_ruble_edit_text"
style="#style/RateEditText"
android:hint="#string/description_currency_ruble"
app:met_baseColor="#android:color/black"
app:met_bottomTextSize="#dimen/density_font_size_text_converter"
app:met_errorColor="#color/red_light"
app:met_floatingLabel="normal"
app:met_floatingLabelAlwaysShown="true"
app:met_floatingLabelTextSize="#dimen/density_font_size_text_converter"
app:met_helperText=""
app:met_primaryColor="#color/red_light"
app:met_textColorHint="#android:color/transparent"/>
<com.rengwuxian.materialedittext.MaterialEditText
android:id="#+id/converter_dollar_edit_text"
style="#style/RateEditText"
android:hint="#string/description_currency_dollar"
app:met_baseColor="#android:color/black"
app:met_bottomTextSize="#dimen/density_font_size_text_converter"
app:met_errorColor="#color/red_light"
app:met_floatingLabel="normal"
app:met_floatingLabelAlwaysShown="true"
app:met_floatingLabelTextSize="#dimen/density_font_size_text_converter"
app:met_helperText=""
app:met_primaryColor="#color/red_light"
app:met_textColorHint="#android:color/transparent"/>
<com.rengwuxian.materialedittext.MaterialEditText
android:id="#+id/converter_euro_edit_text"
style="#style/RateEditText"
android:hint="#string/description_currency_euro"
app:met_baseColor="#android:color/black"
app:met_bottomTextSize="#dimen/density_font_size_text_converter"
app:met_errorColor="#color/red_light"
app:met_floatingLabel="normal"
app:met_floatingLabelAlwaysShown="true"
app:met_floatingLabelTextSize="#dimen/density_font_size_text_converter"
app:met_helperText=""
app:met_primaryColor="#color/red_light"
app:met_textColorHint="#android:color/transparent"/>
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
</ScrollView>
<android.support.design.widget.FloatingActionButton
android:id="#+id/update_floating_action_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="#dimen/density_spacing_size_floating_action_button"
android:layout_marginRight="#dimen/float_action_button_spacing_8"
android:src="#drawable/ic_cached_white_24dp"
app:fabSize="mini"
app:layout_anchor="#id/behavior_card_view"
app:pressedTranslationZ="6dp"
app:layout_anchorGravity="end|right|center"
/>
</android.support.design.widget.CoordinatorLayout>
Instead of anchoring to behavior_card_view, try anchoring it to something inside behavior_card_view. Ideally, anchor to the bottom of the USD textview. This should prevent the FAB from sliding down.
I would actually create a invisible layout which I can use to anchor but it doesn't affect the UI otherwise.
I can't replicate the issue you are having but the following works as you want:
<RelativeLayout
android:id="#+id/rl1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingTop="10dp"
android:paddingRight="10dp">
<TextView
android:id="#+id/tv1"
android:layout_width="match_parent"
android:layout_height="100dp"
android:paddingLeft="12dp"
android:text="Setting"
android:focusable="true"
android:focusableInTouchMode="true" />
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="8dp"
android:layout_marginRight="8dp"
android:src="#drawable/ic_add"
app:fabSize="mini"
app:pressedTranslationZ="6dp"
app:layout_anchorGravity="end|right|center"
app:layout_anchor="#id/tv1" />
... a lot of elements here ...
</RelativeLayout>
This RelativeLayout is the only element inside my ScrollView element.
I have the following code
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/itemLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="#dimen/list_view_layout_margin"
android:paddingRight="#dimen/list_view_layout_margin"
android:background="#color/yellow">
<LinearLayout
android:id="#+id/itemLinearLayoutView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#+id/gameNameView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="#dimen/game_list_text_size" />
<TextView
android:id="#+id/gameCreationDateView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/gray"
android:textSize="#dimen/small_text_size"
android:textStyle="italic" />
</LinearLayout>
<LinearLayout
android:id="#+id/LinearLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/red"
android:orientation="horizontal" >
<Button
android:id="#+id/infoButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/info" />
<Button
android:id="#+id/deleteButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/delete" />
</LinearLayout>
</RelativeLayout>
The LinearLayout with id itemLinearLayoutView is the main layout that wrap everything in a row of listview. The problem I am having is that the second linear layout child does not take the height of the parent linear layout with id itemLinearLayoutView. Any solutions? or Problem with the code?
Your problem lies here:
android:layout_height="wrap_content"
This needs to be changed to "match_parent" in the LinearLayout which you want to be the parent's size. Also, you said
the second linear layout child does not take the height of the parent linear layout
These two layouts are not parents and children to one another. The parent is your RelativeLayout and both of your LinearLayouts are equivalent children of that RelativeLayout. Maybe this will help you debug any further problems you encounter.
just change the layout height to match parent . problem will be resolved.
<LinearLayout
android:id="#+id/itemLinearLayoutView"
android:layout_width="match_parent"
// use match_parent instead of wrap_content
android:layout_height="match_parent"
android:orientation="vertical" >
the layout needs to be nested within the first linear layout to take the parameters of it, and the value of the layout height needs to be changed. Code as Follows.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/itemLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="#dimen/list_view_layout_margin"
android:paddingRight="#dimen/list_view_layout_margin"
android:background="#color/yellow">
<LinearLayout
android:id="#+id/itemLinearLayoutView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#+id/gameNameView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="#dimen/game_list_text_size" />
<TextView
android:id="#+id/gameCreationDateView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/gray"
android:textSize="#dimen/small_text_size"
android:textStyle="italic" />
<LinearLayout
android:id="#+id/LinearLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/red"
android:orientation="horizontal" >
<Button
android:id="#+id/infoButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/info" />
<Button
android:id="#+id/deleteButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/delete" />
</LinearLayout>
</LinearLayout>
<LinearLayout
android:id="#+id/itemLinearLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent" <!-- you should use match_parent here -->
android:orientation="vertical" >
// try this way i have used LinearLayout as parent rather than RelativeLayout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/itemLayoutView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingLeft="#dimen/list_view_layout_margin"
android:paddingRight="#dimen/list_view_layout_margin"
android:background="#color/yellow">
<LinearLayout
android:id="#+id/itemLinearLayoutView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="#+id/gameNameView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="#dimen/game_list_text_size" />
<TextView
android:id="#+id/gameCreationDateView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/gray"
android:textSize="#dimen/small_text_size"
android:textStyle="italic" />
</LinearLayout>
<LinearLayout
android:id="#+id/LinearLayoutView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:gravity="right"
android:background="#color/red"
android:orientation="horizontal" >
<Button
android:id="#+id/infoButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/info" />
<Button
android:id="#+id/deleteButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/delete" />
</LinearLayout>
</LinearLayout>
I have RelativeLayout and inside it, there is an ImageView and a TextView, in that order. I want the ImageView to have height of match_parent but I want the RelativeLayout to have height of wrap_content of the TextView inside it. How can I make it so?
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<ImageView
android:id="#+id/photo"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
Use this it will work as I understand your problem
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#CC0000" >
<ImageView
android:id="#+id/photo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:background="#FF9966"
android:layout_alignBottom="#+id/content"
android:layout_alignTop="#+id/content"
android:src="#drawable/ic_launcher" />
<TextView
android:layout_toRightOf="#+id/photo"
android:id="#+id/content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#FF3399"
android:text="asdjajdasdjajdasdjaddtegrgfhfhfhfhhfh" />
</RelativeLayout>
Try this..
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<ImageView
android:id="#+id/photo"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<TextView
android:id="#+id/content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
/>
</RelativeLayout>
I am using android:layout_alignParentBottom="true" to align at parent bottom but for this particular case is not valid. Parent is a relative layout that has fixed size and bigger that screen height. Now I need to place a textview aligned at bottom of screen and not parent bottom. How to reach it? thank you.
<?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="600dp" >
<RelativeLayout
android:id="#+id/blogLayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<WebView
android:id="#+id/webviewBlog"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:textColor="#android:color/black"
android:scrollbars="none"
android:fitsSystemWindows="true" />
</RelativeLayout>
<RelativeLayout
android:id="#+id/Volver"
android:layout_width="fill_parent"
android:layout_height="40dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true">
<TextView
android:id="#+id/Volvertxt"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:text="Volver"
android:textColor="#android:color/white"
android:textSize="30px"
android:gravity="center"
android:clickable="true"
android:onClick="onClickVolver" />
</RelativeLayout>
</RelativeLayout>
I have modified your code hope it solves your problem
<?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="fill_parent" >
<WebView
android:id="#+id/webviewBlog"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:textColor="#android:color/black"
android:scrollbars="none"
android:fitsSystemWindows="true" />
<TextView
android:id="#+id/Volvertxt"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:text="Volver"
android:textColor="#android:color/white"
android:textSize="30px"
android:gravity="center"
android:clickable="true"
android:onClick="onClickVolver" />
</RelativeLayout>
That is because, you are giving height in dp units of the parent layout. Make it match_parent.
EDIT:
<?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" >
<WebView
android:id="#+id/webviewBlog"
android:layout_width="fill_parent"
android:layout_height="600dp"
android:textColor="#android:color/black"
android:scrollbars="none"
android:fitsSystemWindows="true" />
<RelativeLayout
android:id="#+id/Volver"
android:layout_width="fill_parent"
android:layout_height="40dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true">
<TextView
android:id="#+id/Volvertxt"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:text="Volver"
android:textColor="#android:color/white"
android:textSize="30px"
android:gravity="center"
android:clickable="true"
android:onClick="onClickVolver" />
</RelativeLayout>
</RelativeLayout>