的Android按鈕背景狀態

Question

我有一個Button有底色的ressource定義狀態和背景

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

    <item android:drawable="@color/white" android:state_pressed="true" /> 
    <item android:drawable="@color/gray" android:state_pressed="false" /> 

    <item android:drawable="@color/white" android:state_selected="true" /> 
    <item android:drawable="@color/gray" android:state_selected="false" /> 

</selector> 

當按下它改變顏色我也試過

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

    <item android:drawable="@color/white" android:state_pressed="true" android:state_selected="true" /> 
    <item android:drawable="@color/gray" android:state_pressed="false" android:state_selected="false" /> 

</selector> 

，但是當我應用btn.setSelected(true);什麼也沒有發生

有什麼想法？

Answer 1

嘗試btn.performClick();，點擊按鈕。這可能會實現：

void pressButton(Button btn, boolean pressed) { 
    if (pressed != btn.isPressed()) { 
     btn.performClick(); 
    } 
} 

Answer 2

好，我知道了，

爲未來的人誰都會遇到這樣的，這已經解決了這個問題

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

    <item android:drawable="@color/white" android:state_pressed="true" /> 
    <item android:drawable="@color/white" android:state_selected="true" /> 
    <item android:drawable="@color/tab_gray" /> 

</selector>