[Android L] Android Material圆形按钮

Question

http://imgur.com/KafNkf8

那么,有人会如何实现在android L中展示的循环按钮？还有什么是圆形按钮的技术名称,XML代码将不胜感激.

Answer 1

该按钮称为FAB(浮动操作按钮),制作起来非常简单.

Activity.java

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layoutfab);

        //Outline
        int size = getResources().getDimensionPixelSize(R.dimen.fab_size);
        Outline outline = new Outline();
        outline.setOval(0, 0, size, size);
        findViewById(R.id.fab).setOutline(outline);
    }

}

anim.xml

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:state_enabled="true"
        android:state_pressed="true">
        <objectAnimator
            android:duration="@android:integer/config_shortAnimTime"
            android:propertyName="translationZ"
            android:valueFrom="@dimen/button_elevation"
            android:valueTo="@dimen/button_press_elevation"
            android:valueType="floatType" />
    </item>
    <item>
        <objectAnimator
            android:duration="@android:integer/config_shortAnimTime"
            android:propertyName="translationZ"
            android:valueFrom="@dimen/button_press_elevation"
            android:valueTo="@dimen/button_elevation"
            android:valueType="floatType" />
    </item>
</selector>

dimens.xml

<resources>
    <dimen name="fab_size">56dp</dimen>

    <dimen name="button_elevation">2dp</dimen>
    <dimen name="button_press_elevation">4dp</dimen>
</resources>

和你的布局文件来定义FAB按钮.

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <ImageButton
        android:id="@+id/fab"
        android:layout_alignParentRight="true"
        android:layout_alignParentBottom="true"
        android:layout_width="@dimen/fab_size"
        android:layout_height="@dimen/fab_size"
        android:layout_gravity="bottom|right"
        android:layout_marginRight="16dp"
        android:layout_marginBottom="16dp"
        android:background="@drawable/ripple"
        android:stateListAnimator="@anim/anim"
        android:src="@drawable/ic_action_add"
        android:elevation="4dp"
        />


</RelativeLayout>

最后按下按钮时会产生波纹.ripple.xml

<ripple xmlns:android="http://schemas.android.com/apk/res/android" android:color="?android:colorControlHighlight">
    <item>
        <shape android:shape="oval">
            <solid android:color="?android:colorAccent" />
        </shape>
    </item>
</ripple>

享受您的新FAB.请记住这只适用于Android L!

编辑 此更新于:https://stackoverflow.com/a/24548910/4352176

Answer 2

有一个更简单的版本(v7)方式:

<ImageButton style="@style/AppTheme"
    android:layout_width="60dp"
    android:layout_height="60dp"
    android:text="New Button"
    android:id="@+id/OkBt"
    android:elevation="10dp"
    android:src="@drawable/ic_keyboard_return_black_36dp"
    android:background="@drawable/circle" />

看看style ="@ style/AppTheme"我为旧版本设置的样式是:

<style name="AppTheme" parent="AppTheme.Base"/>

<style name="AppTheme.Base" parent="Theme.AppCompat.Light.DarkActionBar">

对于Android棒棒糖是:

<style name="AppTheme" parent="android:Theme.Material.Light.DarkActionBar">

圆形的形状是:

<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval">
    <solid android:color="#81D4FA"/>
</shape>

它适用于所有Android版本,它会在Lollipop中自动生成圆形阴影.