Android radiobutton图像

Question

我有一个定制radiobuttons的radiogroup.图标设置使用

rbFirst.setButtonDrawable(R.drawable.first);

但图标不在中心,我该如何解决？我在xml文件和类内部尝试了不同的属性,但它没有任何效果.

Answer 1

尝试使用setGravity(Gravity.CENTER);将其设置为背景drawable.

或者,如果它没有帮助,您将不得不从RadioButton派生一个新类并覆盖onDraw().

这是布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<org.test.TestProj.RadioButtonCenter
    android:id="@+id/myview"
    android:layout_width="fill_parent" 
    android:layout_height="100dp" 
    android:layout_centerInParent="true"
    android:text="Button test"
    />
</RelativeLayout>

代码:

package org.test.TestProj;

import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.Gravity;
import android.widget.RadioButton;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;

public class RadioButtonCenter extends RadioButton {

    public RadioButtonCenter(Context context, AttributeSet attrs) {
        super(context, attrs);
        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CompoundButton, 0, 0);
        buttonDrawable = a.getDrawable(1);
        setButtonDrawable(android.R.color.transparent);
    }
    Drawable buttonDrawable;


     @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);

            if (buttonDrawable != null) {
                buttonDrawable.setState(getDrawableState());
                final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK;
                final int height = buttonDrawable.getIntrinsicHeight();

                int y = 0;

                switch (verticalGravity) {
                    case Gravity.BOTTOM:
                        y = getHeight() - height;
                        break;
                    case Gravity.CENTER_VERTICAL:
                        y = (getHeight() - height) / 2;
                        break;
                }

            int buttonWidth = buttonDrawable.getIntrinsicWidth();
            int buttonLeft = (getWidth() - buttonWidth) / 2;
            buttonDrawable.setBounds(buttonLeft, y, buttonLeft+buttonWidth, y + height);
                buttonDrawable.draw(canvas);
            }
        }   
}

最后,这是一个需要放入res/values的attrs.xml文件,以便代码可以获得平台定义的属性.

<?xml version="1.0" encoding="utf-8"?>
<resources>    
     <declare-styleable name="CompoundButton">
        <attr name="android:button" />
    </declare-styleable>
</resources>