Meaning of layoutopt tool output

I use layoutopt like 'layoutopt layout.xml'

And I get this message:

9:18 This tag and its children can be replaced by one <TextView/> and a compound drawable
28:78 Use an android:layout_height of 0dip instead of wrap_content for better performance

But I do not understand the meaning, can someone clarify me the meaning of it

use 0dip on what? on the layout? I want my layout to wrap the content not to be zero size height

<LinearLayout android:id="@+id/linearLayout3"
   android:layout_width="fill_parent" android:layout_height="0px"
   android:layout_alignParentTop="true" android:background="#30000000"
   android:padding="5dip">

   <ImageView android:id="@+id/imageView1"
      android:layout_width="wrap_content" android:layout_height="wrap_content"
      android:background="@drawable/bzz_icon"></ImageView>

   <TextView android:layout_width="fill_parent" android:id="@+id/textView1"
      android:textColor="#FFFFFF" android开发者_StackOverflow中文版:layout_height="wrap_content"
      android:layout_gravity="center" android:gravity="left"
      android:layout_marginLeft="15dip" android:text="@string/title"
      android:textSize="20sp"></TextView>

</LinearLayout>

The first message is saying that you can replace your linearLayout3 with only a TextView and use android:drawableLeft instead of the ImageView.

The second message is probably telling you that on whatever is at line 28 of your layout you can use layout_height of 0dp instead of wrap_content. This is usually used in conjunction with layout_weight when your element will be expanded anyway. However, this is just a guess and you should post your entire layout XML, including line 28, so that we can better figure out the meaning of the message.

TextView with the left image and the text is centered

  <TextView
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:gravity="center|left"
            android:drawableLeft="@drawable/ic_launcher"
            android:text="@string/hello" />