我想更新的选择器编程的按钮。

I want to update the selector for a button programmatically.

我可以与下面给出

<?xml version="1.0" encoding="UTF-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
   <item android:state_enabled="false"
         android:drawable="@drawable/btn_off" />
   <item android:state_pressed="true"
         android:state_enabled="true" 
         android:drawable="@drawable/btn_off" />
   <item android:state_focused="true"
         android:state_enabled="true" 
         android:drawable="@drawable/btn_on" />
   <item android:state_enabled="true" 
         android:drawable="@drawable/btn_on" />
</selector>

我想以编程方式做同样的事情。我曾尝试类似下面

I want to do the same thing programmatically. I have tried something like given below

private StateListDrawable setImageButtonState(int index)
{
    StateListDrawable states = new StateListDrawable();

    states.addState(new int[] {android.R.attr.stateNotNeeded},R.drawable.btn_off); 
    states.addState(new int[] {android.R.attr.state_pressed, android.R.attr.state_enabled},R.drawable.btn_off);
    states.addState(new int[] {android.R.attr.state_focused, android.R.attr.state_enabled},R.drawable.btn_on);
    states.addState(new int[] {android.R.attr.state_enabled},R.drawable.btn_on);

    return states;
}

但它没有工作。

but it didnt work.

和如何设置安卓state_enabled =假或安卓state_enabled =真正的编程。

在此先感谢。

推荐答案

您需要使用状态所需要的负值。 例如：

You need to use the negative value of the needed state. E.g.:

states.addState(new int[] {-android.R.attr.state_enabled},R.drawable.btn_disabled);

请注意， - 符号前 android.R.attr.state_enabled