How to set View width (height) in percentage of parent View in Android

How to set View width (height) in percentage of parent View in Android

Example:
I want to set child LinearLayout height = 50% of parrent LinearLayout in Android. Like in HTML.

To set height in percents I do some trick with android:layout_weight and android:weightSum

Here the screenshot:

To do this you need do somethind like this. Look at code below:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:weightSum="100">
 <LinearLayout android:layout_weight="50"
  android:layout_width="match_parent"
  android:id="@+id/linearLayout1"
  android:layout_height="wrap_content"
  android:orientation="vertical"></LinearLayout>
</LinearLayout>

Android - How to merge two layout XML in Android?

Android - How to merge two layout XML in Android?

In Android, we can merge two seperate layout XML's into a single XML. It is done using and tags.

  - The tag does exactly what its name suggests; it includes another XML layout, i.e., means takes that file and paste its contents here. In the only the layout attribute is required. The attribute, without the android prefix, is a reference to the layout file you wish to include.

- The layout which we have to use must be enclosed under tag, so that we can include layouts from other xmls. The tag was created for the purpose of optimizing Android layouts by reducing the number of levels in view trees.

Ex:

Let's create a new Android project and add new Android XML file into "res/layout" folder and name it as "main1".

Now we have two layout main.xml and main1.xml as shown below.

Now we will merge these two layout XML into single layout.

main.xml

Above code  you can see that we included a xml file named main1.xml

main1.xml

Build and Run the project. You will see the merged layout like this.

Layout technique: Center a TextView with a Button left and right

Layout technique: Center a TextView with a Button left and right

While working on an application which should look similar to an iPhone application, I have to create a bar at the top where I have a back and a forward button (each on one side) and a dynamic text centered in the middle between them.
To get this done, I searched quite a lot and got it finally to work.
The surrounding layout should be the RelativeLayout with two Buttons (in my case I used ImageViews) and a TextView.

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<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="50dip" android:background="#666666" android:paddingTop="3dip"> <ImageView android:id="@+id/buttonLeft" android:layout_width="50dip" android:layout_height="50dip" android:layout_alignParentLeft="true" android:paddingLeft="3dip" android:scaleType="centerInside" android:clickable="true" android:src="@drawable/buttonLeft"/> <TextView android:id="@+id/title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerHorizontal="true" android:layout_centerVertical="true" android:textColor="#000000" android:textSize="20dip" android:textStyle="bold" android:text="@string/titleText"/> <ImageView android:id="@+id/buttonRight" android:layout_width="50dip" android:layout_height="50dip" android:layout_alignParentRight="true" android:paddingRight="3dip" android:scaleType="centerInside" android:clickable="true" android:src="@drawable/buttonRight"/> </RelativeLayout>

As you can see, there are some layout params the auto completion didn’t list at all.
The params layout_centerVertical / layout_centerHorizontal do what they are named for and layout_alignParentRight / layout_alignParentLeft are like the CSS float: left / right.

Last tipp: If you have an application with different activitys/layouts but with some repeating layout parts, like the bar at the top, try to use the Tag.