问题
The thumb for my Switch-button seems to get skewed(for on&off state). There were similar problems on github, but those were for people making libraries to support Switch button in API 4.0-
main contains the switch-button, and there is a thumb and track drawable applied to it
This is what is happening:
This is how its suppose to loook:
switch_track_on.png
main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Switch
android:id="@+id/switch1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="112dp"
android:thumb="@drawable/switch_thumb_selector"
android:track="@drawable/switch_track_selector"
android:textOn=""
android:textOff=""/>
</RelativeLayout>
switch_thumb_selector.xml
<selector>
<item android:drawable="@drawable/switch_thumb">
</item>
</selector>
switch_track_selector.xml
<selector>
<item android:drawable="@drawable/switch_track_on" android:state_checked="true"/>
<item android:drawable="@drawable/switch_track_off" android:state_checked="false"/>
</selector>
回答1:
I had the same requirement. I checked Android code and found that
- switch ignores any vertical margin/padding applied to a thumb shape drawable (thus thumb always touch the top and bottom of the track)
- the width of the thumb is calculated by taking the horizontal paddings + the max width of the on and off texts.
This makes really hard to make a circle thumb.
But if you specify the thumb drawable as a layer drawable for the sole reason to be able to specify padding for the single layer of the drawable, you can get the desired effect.
Thumb selector:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<!--
NOTE
We want a thumb with padding around it inside the track.
Sadly, a switch draws its track and thumb with the same height ignoring
any padding of the drawable, so using a shape with padding does not work.
To overcome, we apply a trick. We create layer list because the
LayerListDrawable draws itself with taking the top, left, right, bottom
values into account.
-->
<layer-list>
<item
android:top="@dimen/switch_thumb_padding"
android:left="@dimen/switch_thumb_padding"
android:right="@dimen/switch_thumb_padding"
android:bottom="@dimen/switch_thumb_padding">
<!--
NOTE
No need to specify size because:
- The thumb fills the track in height.
- The thumb width is determined from thumb max(on, off) text +
text padding + drawable padding.
-->
<shape android:shape="oval">
<solid android:color="@color/switch_thumb"/>
<!-- NOTE did not work, had to set Switch's thumbTextPadding to the radius -->
<!--
<padding android:right="@dimen/switch_thumb_radius"
android:left="@dimen/switch_thumb_radius"/>
-->
</shape>
</item>
</layer-list>
</item>
</selector>
I set the on and off text of switch to empty (actually to "" to prevent warning about empty resource).
track:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_enabled="false">
<shape android:shape="rectangle">
<size android:height="@dimen/switch_track_height"/>
<corners android:radius="@dimen/switch_thumb_radius"/>
<solid android:color="@color/switch_track_off"/>
</shape>
</item>
<item android:state_checked="true">
<shape android:shape="rectangle">
<size android:height="@dimen/switch_track_height"/>
<corners android:radius="@dimen/switch_thumb_radius"/>
<solid android:color="@color/switch_track_on"/>
</shape>
</item>
</selector>
Switch style:
<style name="CustomSwitch">
<!-- NOTE this way the switch will be as width as required minimally -->
<item name="android:switchMinWidth">0dp</item>
<item name="android:track">@drawable/switch_track</item>
<item name="android:thumb">@drawable/switch_thumb</item>
<item name="android:textOff">@string/switch_thumb_off</item>
<item name="android:textOn">@string/switch_thumb_on</item>
<!-- NOTE if set to 0dp, the thumb was not visible even with padding
of the thumb drawable set to -->
<item name="android:thumbTextPadding">@dimen/switch_thumb_radius</item>-->
<!--<item name="android:thumbTextPadding">0dp</item>-->
</style>
And finally, the dimens:
<dimen name="switch_track_height">30dp</dimen>
<dimen name="switch_thumb_radius">15dp</dimen>
<dimen name="switch_thumb_padding">2dp</dimen>
So the only 'tricky' thing is to keep height = radius * 2.
回答2:
For Custom Switch (Like IOS switch) I tried below Steps:
Create a drawable track_selector.xml:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_checked="true">
<shape android:dither="true" android:shape="rectangle" android:useLevel="false" android:visible="true">
<solid android:color="#ca120f" />
<corners android:radius="25dp" />
<size android:width="2dp" android:height="18dp" />
</shape>
</item>
<item android:state_checked="false">
<shape android:dither="true" android:shape="rectangle" android:useLevel="false" android:visible="true">
<solid android:color="#27170432" />
<corners android:radius="25dp" />
<size android:width="2dp" android:height="18dp" />
</shape>
</item>
</selector>
Create a drawable thumb_selector.xml:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_checked="false">
<shape android:dither="true" android:shape="rectangle" android:useLevel="false" android:visible="true">
<solid android:color="#ffffff" />
<corners android:radius="100dp" />
<size android:width="24dp" android:height="25dp" />
<stroke android:width="4dp" android:color="#0000ffff" />
</shape>
</item>
</selector>
In your layout :
<Switch
android:id="@+id/checkboxAttendanceSelector"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_centerVertical="true"
android:thumb="@drawable/thumb_selector"
app:track="@drawable/track_selector" />
Its working fine for me.
回答3:
No clue why this happens but solved it by placing the Switch-button within a linearLayout. There must be some propery(width) of the thumb that has a "match_parent" of some sort that must've been causing it.
Edit: It happens when I remove the default 'ON' and 'OFF' text. So to hide the text i changed its color to white. How to change textcolor of switch in Android
main.java
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.toggle_button);
Switch sw = (Switch) findViewById(R.id.switch1);
//Both of these need to be used to change the text color to white
sw.setTextColor(Color.WHITE);
sw.setSwitchTextAppearance(this, Color.WHITE);
//Doing this would skew the circle
//sw.setTextOn(" ");
//sw.setTextOff(" ");
}
main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="70dp" >
<Switch
android:id="@+id/switch1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:thumb="@drawable/switch_thumb_selector"
android:track="@drawable/switch_track_selector" />
</LinearLayout>
回答4:
You can always horizontally stretch the graphic itself (ie, "switch_thumb.png") if you can't use the other answers.
If you use the original software used to design the graphic and re-export it after stretching, it shouldn't cause blurring of the image. You'll have to eye-ball it for your dimensions, but starting at +30% stretching should get you close.
来源：https://stackoverflow.com/questions/22726408/switch-button-thumb-gets-skewed