当我向一个州添加多个州 <item> 在状态列表可绘制对象中，它停止工作。 为什么？

Question

What I want:

An ImageView with a transparent background. When it is clicked, its background should turn blue, and should remain blue until something else is clicked. I am using state-list drawable for it.

What is happening:

The code is given as follows. The problem is that the background does turn blue, but it does not remain blue. So I thought it is because android:state_pressed just represents the moment when the widget is being clicked. So I also added android:state_selected="true" to button_state_list_drawable.xml right after android:state_pressed="true" . What happened then is that the background stopped turning blue even when the imageview is being clicked.

How do I fix this?

ImageView defined in XML like this:

<ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/fragment_imageView"
        android:src="@drawable/ic_photo"
        android:background="@drawable/button_state_list_drawable"
        android:clickable="true" />

The button_state_list_drawable.xml is:

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

    <item android:drawable="@drawable/button_pressed_state_drawable"
        android:state_pressed="true"
        android:state_selected="true" />

    <item android:drawable="@drawable/button_enabled_state_drawable" />

</selector>

The button_pressed_state_drawable.xml is:

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

    <size android:width="50dp"
        android:height="50dp" />

    <padding android:left="25dp"
        android:right="25dp"
        android:top="25dp"
        android:bottom="25dp" />

    <stroke android:color="#fff"
        android:width="1dp" />

    <solid android:color="#1aafd0" />

</shape>

The button_enabled_state_drawable.xml is:

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

    <size android:width="50dp"
        android:height="50dp" />

    <padding android:left="25dp"
        android:right="25dp"
        android:top="25dp"
        android:bottom="25dp" />

    <stroke android:color="#fff"
        android:width="1dp" />

    <solid android:color="@android:color/transparent" />

</shape>

Answer 1

I don´t know if this is the solution, but I have to show some code. You haven´t added a default state to your selector and I can´t see your selected state (you wrote it in yur question, but you haven´t posted it). It must be something like this:

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


   <item android:drawable="@drawable/button_enabled_state_drawable"
        android:state_enabled="true" />

   <item android:drawable="@drawable/button_pressed_state_drawable"
        android:state_pressed="true" />

    <item android:drawable="@drawable/your_selected_state_drawable"
        android:state_selected="true" />

    <item android:drawable="@drawable/your_button_default_drawable"/>

</selector>

And I think you have to add programmatically the selected state (I´m not sure for this or if it does it automatically)

yourImageView.setOnClickListener(new OnClickListener(){
      @Override
  public void onClick(View v){

        if(yourImageView.isSelected()){
            yourImageView.setSelected(false);
          }else{
            yourImageView.setSelected(true);
          }
    }
});

Answer 2

I recently had this problem, and this is what I did.

In your button_state_list_drawable.xml, add this somewhere before you default state item:

<item android:drawable="@drawable/button_pressed_state_drawable"
        android:state_selected="true"
        android:state_pressed="false" />

Also remove android:state_selected="true" from your state_pressed item.

Then in the beginning of your click listener for the ImageView , write

yourImageView.setSelected(true);

This had solved my problem. Hope it helps you.