通过在Android中以编程方式更改布局的背景色

Question

I have to develop one android application.

I have to display the background color is #424340 for normal state.but i have to click these layout(selected and pressed state) means have to change the background color is #FF0000.How can i do programmatically...please give me solution for these...

I have used below code for creating layout programmtically:

LinearLayout ar = new LinearLayout(this);
            ar.setOrientation(LinearLayout.VERTICAL);
            ar.setPadding(3, 3, 3, 3);

            ar.setLayoutParams(artiLayoutParams);
            ar.setGravity(Gravity.CENTER); 
            ar.setBackgroundDrawable(getResources().getDrawable(R.drawable.list_selector));

Here i ahve to click these layout means change the background color.so i ahve using below code.please check it.

list_selector.xml:

<?xml version="1.0" encoding="utf-8"?>
 <selector xmlns:android="http://schemas.android.com/apk/res/android">
 <!-- Selector style for listrow -->
 <item 

 android:state_selected="false"
 android:state_pressed="false" 
android:state_focused="false"
android:drawable="@drawable/gradient_bg" />
<item android:state_pressed="true"
android:state_selected="true" 
android:state_focused="true"
android:drawable="@drawable/gradient_bg_hover" />
 </selector>

gradient_bg.xml:

    <?xml version="1.0" encoding="utf-8"?>



  <shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
        <stroke android:width="3dp" android:color="#424340" />

        <padding android:left="3dp" android:top="3dp" android:right="3dp"
            android:bottom="3dp" />
        <corners android:radius="4dp" />
    </shape>

gradient_bg_hover.xml:

    <?xml version="1.0" encoding="utf-8"?>

  <shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

        <stroke android:width="3dp" android:color="#FF0000" />
         <padding android:left="3dp" android:top="3dp" android:right="3dp"
            android:bottom="3dp" />

        <corners android:radius="4dp" />
        </shape> 

But my background color is didn't change.Whats wrong in my code.please help me...

Answer 1

Your states seem wrong. Can you try this to confirm if it works?

<?xml version="1.0" encoding="utf-8"?>
 <selector xmlns:android="http://schemas.android.com/apk/res/android">
 <!-- Selector style for listrow -->
 <item 
 android:state_pressed="false"
android:drawable="@drawable/gradient_bg" />
<item android:state_pressed="true"
android:drawable="@drawable/gradient_bg_hover" />
 </selector>