仿iOS Segmented Control样式"
同步发表于http://avenwu.net/2015/02/05/styled_radiogroup_segmented_control
Fork on github https://github.com/avenwu/support
iOS中有一个Segmented Control组件，android中的RadioGroup与之类似，但是RadioGroup的默认样式不是很美观，但是只需要稍微调一下就可以长得和Segmented Control控件一样简洁优雅。
实现
直接写style文件当然是最快的,只需设置每个RadioButton的对其为居中，修改默认的android:button资源，然后加上背景、文字的selector。
<RadioGroup
android:layout_width="match_parent"
android:layout_height="48dp"
android:orientation="horizontal"
android:gravity="center_vertical">
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="A"
android:id="@+id/radioButton"
style="@style/FlatRadioButtonStyle"
android:background="@drawable/flat_round_shape_left" />
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="B"
android:id="@+id/radioButton2"
android:checked="true"
style="@style/FlatRadioButtonStyle"
android:background="@drawable/flat_round_shape_middle" />
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="C"
android:id="@+id/radioButton3"
style="@style/FlatRadioButtonStyle"
android:background="@drawable/flat_round_shape_right" />
</RadioGroup>style样式
<style name="FlatRadioButtonStyle">
<item name="android:layout_weight">1</item>
<item name="android:button">@null</item>
<item name="android:gravity">center</item>
<item name="android:textAppearance">?android:textAppearanceMedium</item>
<item name="android:textColor">@color/radio_button_color</item>
<item name="android:padding">5dp</item>
</style>背景selector
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_checked="true">
<shape android:shape="rectangle">
<corners android:topLeftRadius="5dp" android:bottomLeftRadius="5dp" />
<solid android:color="@android:color/white" />
<stroke android:color="@android:color/white" android:width="1dp" />
</shape>
</item>
<item>
<shape android:shape="rectangle">
<corners android:topLeftRadius="5dp" android:bottomLeftRadius="5dp" />
<solid android:color="@android:color/transparent" />
<stroke android:color="@android:color/white" android:width="1dp" />
</shape>
</item>
</selector>这些都没什么问题，但是比较零散，每次都需要写很多的xml及其样式，selector等，所以可以做一些简单的封装，暴露一些必要的属性用于自定义，比如边框线的宽度，背景色等。
简单封装
自定义RadioGroup，将必要的初始化配置在内部完成。
package net.avenwu.support.widget;
import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.GradientDrawable;
import android.graphics.drawable.StateListDrawable;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import net.avenwu.support.R;
/**
* Created by chaobin on 2/4/15.
*/
public class FlatTabGroup extends RadioGroup {
public FlatTabGroup(Context context) {
this(context, null);
}
private int mRadius;
private int mStroke;
private int mHighlightColor;
private String[] mItemString;
private float mTextSize;
private ColorStateList mTextColor;
public FlatTabGroup(Context context, AttributeSet attrs) {
super(context, attrs);
setOrientation(HORIZONTAL);
setGravity(Gravity.CENTER_VERTICAL);
TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.FlatTabGroup);
mHighlightColor = array.getColor(R.styleable.FlatTabGroup_tab_border_color, Color.WHITE);
mStroke = array.getDimensionPixelSize(R.styleable.FlatTabGroup_tab_border_width, 2);
mRadius = array.getDimensionPixelOffset(R.styleable.FlatTabGroup_tab_radius, 5);
mTextColor = array.getColorStateList(R.styleable.FlatTabGroup_tab_textColor);
mTextSize = array.getDimensionPixelSize(R.styleable.FlatTabGroup_tab_textSize, 14);
array.recycle();
int id = array.getResourceId(R.styleable.FlatTabGroup_tab_items, 0);
mItemString = isInEditMode() ? new String[]{"TAB A", "TAB B", "TAB C"} : context.getResources().getStringArray(id);
generateTabView(context, attrs);
updateChildBackground();
}
private void generateTabView(Context context, AttributeSet attrs) {
if (mItemString == null) {
return;
}
for (String text : mItemString) {
RadioButton button = new RadioButton(context, attrs);
button.setGravity(Gravity.CENTER);
button.setButtonDrawable(android.R.color.transparent);
button.setText(text);
button.setTextColor(mTextColor);
button.setTextSize(TypedValue.COMPLEX_UNIT_PX, mTextSize);
addView(button, new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT, 1));
}
}
@Override
protected void onFinishInflate() {
super.onFinishInflate();
updateChildBackground();
}
private void updateChildBackground() {
for (int i = 0; i < getChildCount(); i++) {
View child = getChildAt(i);
if (child instanceof RadioButton) {
child.setBackgroundDrawable(generateTabBackground(i, mHighlightColor));
}
}
}
private Drawable generateTabBackground(int position, int color) {
StateListDrawable stateListDrawable = new StateListDrawable();
stateListDrawable.addState(new int[]{android.R.attr.state_checked}, generateDrawable(position, color));
stateListDrawable.addState(new int[]{}, generateDrawable(position, Color.TRANSPARENT));
return stateListDrawable;
}
private Drawable generateDrawable(int position, int color) {
float[] radius;
if (position == 0) {
radius = new float[]{
mRadius, mRadius,
0, 0,
0, 0,
mRadius, mRadius
};
} else if (position == getChildCount() - 1) {
radius = new float[]{
0, 0,
mRadius, mRadius,
mRadius, mRadius,
0, 0
};
} else {
radius = new float[]{
0, 0,
0, 0,
0, 0,
0, 0
};
}
GradientDrawable shape = new GradientDrawable();
shape.setCornerRadii(radius);
shape.setColor(color);
shape.setStroke(mStroke, mHighlightColor);
return shape;
}
}属性
定义需要暴露给外面的属性
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="FlatTabGroup">
<attr name="tab_items" format="reference" />
<attr name="tab_border_width" format="dimension|reference" />
<attr name="tab_border_color" format="color|reference" />
<attr name="tab_radius" format="dimension|reference" />
<attr name="tab_textColor" format="dimension|reference" />
<attr name="tab_textSize" format="dimension|reference" />
</declare-styleable>
</resources>现在需要写一个RadioGroup时只需要少量的的配置：
- app:tab_border_width="1dp" 边线宽度
- app:
:color/white" 边线颜色
- **app:
* tabs字符串数组
- app:tab_radius="5dp" 边框弧度
- app:tab_textSize="16sp" 文本字号
- **app: * 文本颜色selector
示例：
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color_light_blue"
android:paddingTop="5dp"
android:paddingBottom="5dp" />所以现在写RadioGroup就非常方便，只需要根据需求配置相应属性即可。比如实现文章开头的效果，可以这样：
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/ll_container">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:orientation="vertical"
android:background="@android:color/holo_red_dark">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="RadioGroup with custom style"
android:textColor="@android:color/white"
android:layout_marginTop="10dp"
android:layout_marginBottom="10dp" />
<RadioGroup
android:layout_width="match_parent"
android:layout_height="48dp"
android:orientation="horizontal"
android:gravity="center_vertical">
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="A"
android:id="@+id/radioButton"
style="@style/FlatRadioButtonStyle"
android:background="@drawable/flat_round_shape_left" />
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="B"
android:id="@+id/radioButton2"
android:checked="true"
style="@style/FlatRadioButtonStyle"
android:background="@drawable/flat_round_shape_middle" />
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="C"
android:id="@+id/radioButton3"
style="@style/FlatRadioButtonStyle"
android:background="@drawable/flat_round_shape_right" />
</RadioGroup>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Custom FlatTabGroup extend RadioGroup"
android:textColor="@android:color/white"
android:layout_marginTop="10dp" />
</LinearLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:background="@android:color/holo_red_dark">
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color"
android:paddingTop="5dp"
android:paddingBottom="5dp" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:background="@color/tab_orange">
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color_orange"
android:paddingTop="5dp"
android:paddingBottom="5dp" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:background="@color/tab_purple">
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color_purple"
android:paddingTop="5dp"
android:paddingBottom="5dp" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:background="@color/tab_blue">
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color_blue"
android:paddingTop="5dp"
android:paddingBottom="5dp" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:background="@color/tab_light_blue">
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color_light_blue"
android:paddingTop="5dp"
android:paddingBottom="5dp" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="20dp"
android:background="@color/tab_green">
<net.avenwu.support.widget.FlatTabGroup
android:layout_width="match_parent"
android:layout_height="40dp"
app:tab_border_width="1dp"
app:tab_border_color="@android:color/white"
app:tab_items="@array/demo_array"
app:tab_radius="5dp"
app:tab_textSize="16sp"
app:tab_textColor="@color/radio_button_color_green"
android:paddingTop="5dp"
android:paddingBottom="5dp" />
</FrameLayout>
</LinearLayout>
</ScrollView>颜色selector
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="@color/tab_light_blue" android:state_checked="true" />
<item android:color="@android:color/white" />
</selector>tab数组
<string-array name="demo_array">
<item>A</item>
<item>B</item>
<item>C</item>
</string-array>小结
完整代码可以再这里获取：
https://github.com/avenwu/support/blob/master/sample/src/main/java/com/avenwu/deepinandroid/StyledRadioButtonDemo.java