title: How to set layout margin dynamically on android
body: <p>my app contains 3 imageviews and i used a textview as a place holder,here is my layout.xml</p>
  
  <pre><code>&lt;LinearLayout 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"
  android:orientation="vertical"
  android:background="@layout/back"
  android:paddingBottom="@dimen/activity_vertical_margin"
  android:paddingLeft="@dimen/activity_horizontal_margin"
  android:paddingRight="@dimen/activity_horizontal_margin"
  android:paddingTop="@dimen/activity_vertical_margin"
  tools:context=".SplasActivity" &gt;
  
  &lt;TextView
      android:id="@+id/textView1"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center"
      android:text="    " /&gt;
  
  &lt;ImageView
      android:id="@+id/imageView1"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center"
      android:scaleType="fitXY"
      android:src="@drawable/list_sher" /&gt;
  
  &lt;ImageView
      android:id="@+id/imageView2"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center"
      android:scaleType="fitXY"
      android:src="@drawable/list_shaer" /&gt;
  
  &lt;ImageView
      android:id="@+id/imageView3"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center"
      android:scaleType="fitXY"
      android:src="@drawable/list_fav" /&gt;
  </code></pre>
  
  <p></p>
  
  <p>then i used below codes to change image sizes,it works fine but when i set margins for my textview, everything goes crazy. textview stays but i cant see any imageview ! </p>
  
  <pre><code>private void setsize(){
      // this codes work fine //
      DisplayMetrics dm=new DisplayMetrics();
      getWindowManager().getDefaultDisplay().getMetrics(dm);
      int w=dm.widthPixels;
      int h=dm.heightPixels;
  
      int h2=(h/7);
      int w2=w-((w*10)/100);
      int h3=(h/20)+1;
  
      LinearLayout.LayoutParams pram=new LinearLayout.LayoutParams(w2,h2);
      img1.setLayoutParams(pram);
      img2.setLayoutParams(pram);
      img3.setLayoutParams(pram);
  
  
      // the problem is here //
      LinearLayout ll = new LinearLayout(this);
      ll.setOrientation(LinearLayout.VERTICAL);
  
      LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
      LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
  
      layoutParams.setMargins(0, h3, 0, 0);
      ll.addView(txt1,layoutParams);
  
  }
  </code></pre>