问题
I have some buttons which I set its background color as red, green and blue separately. When I press the button, click event is generated, but there is no change in gui for the user to know the button is pressed. Android button’s default background grayish color changes to orange and come back to grayish color after releasing the pressed state. How to implement this on colored button?
回答1:
That is implemented via a StateListDrawable
, represented by selector
in XML. Reference: http://developer.android.com/guide/topics/resources/drawable-resource.html#StateList
Here is an example of a drawable that will be white by default, black when pressed:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true"
android:drawable="@android:color/black" /> <!-- pressed -->
<item android:drawable="@android:color/white" /> <!-- default -->
</selector>
回答2:
As mentioned by K-Ballo you can use StateListDrawable to implement a view with various different graphics depending on state. In your case Button is the view where two states are Button pressed and button not pressed.
We need to create a buttonselector.xml file in the drawable folder
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/button_not_pressed" android:state_pressed="false" android:state_selected="false"/>
<item android:drawable="@drawable/button_pressed" android:state_pressed="true"/>
</selector>
Create two separate xml files for the state of the button
button_not_pressed.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<gradient
android:startColor="#FFFFFF"
android:centerColor="#FFFFFF"
android:endColor="#FFFFFF"
android:angle="270" />
</shape>
button_pressed.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<gradient
android:startColor="#FF0000"
android:centerColor="#FF0000"
android:endColor="#FF0000"
android:angle="270" />
</shape>
You will notice two html color codes #FF0000 & #FFFFFF which represent background color of the button according to the state.
In you main.xml where you set the style of your custom button
<Button
android:id="@+id/customButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/buttonselector"
android:text="test"
android:textColor="#000000" />
In you activity class add the following two lines
Button customButton = (Button) findViewById(R.id.customButton);
customButton.setBackground(getResources().getDrawable(R.drawable.buttonselector));
Hope it helps
回答3:
Try out this way:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android" >
<item android:state_pressed="true" >
<shape>
<solid
android:color="#1E669B" />
<stroke
android:width="2dp"
android:color="#1B5E91" />
<corners
android:radius="6dp" />
<padding
android:left="10dp"
android:top="10dp"
android:right="10dp"
android:bottom="10dp" />
</shape>
</item>
<item>
<shape>
<gradient
android:startColor="#1E669B"
android:endColor="#1E669B"
android:angle="270" />
<stroke
android:width="4dp"
android:color="#1B5E91" />
<corners
android:radius="7dp" />
<padding
android:left="10dp"
android:top="10dp"
android:right="10dp"
android:bottom="10dp" />
</shape>
</item>
</selector>
来源:https://stackoverflow.com/questions/14117086/how-to-change-the-color-of-the-color-button-when-pressed-in-android