Android how to create triangle and rectangle shape programmatically?

Solution 1:

Here it is XML for triangle and rectangle. save it inside drawable folder.

triangle.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
    <item >
        <rotate
            android:fromDegrees="45"
            android:toDegrees="45"
            android:pivotX="-40%"
            android:pivotY="87%" >
            <shape
                android:shape="rectangle"  >
                <stroke android:color="@android:color/transparent" android:width="10dp"/>
                <solid
                    android:color="#000000"  />
            </shape>
        </rotate>
    </item>
</layer-list>

rectangle.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
    <item> 
    <shape android:shape="rectangle">
      <solid android:color="#B2E3FA" /> 
    </shape>
  </item>
</layer-list>

and layout for shape you require.

<RelativeLayout
        android:id="@+id/rlv1"
        android:layout_width="150dp"
        android:layout_height="50dp"
        android:background="@drawable/rectangle" />

    <RelativeLayout
        android:id="@+id/rlv2"
        android:layout_width="50dp"
        android:layout_height="50dp"  
        android:layout_below="@+id/rlv1"
        android:background="@drawable/triangle"
        android:rotation="180" />

set margin according you required.

Source

Solution 2:

If you want a border for your layout

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

    <TextView
        android:id="@+id/text_message"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:background="@drawable/bg_rectangle"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:padding="8dp"
        android:text="Abc"
        />

    <ImageView
        android:id="@+id/image_arrow"
        android:layout_marginTop="-1.5dp"
        android:layout_width="16dp"
        android:layout_height="16dp"
        android:layout_gravity="center_horizontal"
        android:background="@drawable/icon_arrow_down"
        />
</LinearLayout>

bg_rectangle

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#eaeaea" />
    <stroke
        android:width="1dp"
        android:color="#f00" />
    <corners android:radius="8dp" />

</shape>

icon_arrow_down, or you can create triangle by vector like here

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item>
        <rotate
            android:fromDegrees="45"
            android:pivotX="135%"
            android:pivotY="15%"
            android:toDegrees="45"
            >
            <shape android:shape="rectangle">
                <solid android:color="#eaeaea"/>
                <stroke
                    android:width="1dp"
                    android:color="#f00" />
            </shape>
        </rotate>
    </item>
</layer-list>