【android】应用图标Drawable转Bitmap，适配安卓8.0

相信大家在加载应用图标的时候，经常会将得到的Drawable转成Bitmap，代码如下：

Drawable drawable = mPackageManager.getApplicationIcon(packageName);
return ((BitmapDrawable) drawable).getBitmap();

但是如果在Android 8.0上面就会崩溃，提示强转BitmapDrawable出错，具体的原因请参考上一篇文章，关于Android 8.0应用图标的改变，那我们该怎么去获取Bitmap呢，我参考了*上面的一篇文章，然后写成了如下工具类供大家参考：
AppIconHelper.java

package com.apusapps.booster.gm.launchpad.utils;

import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;

/**
 * Created by wangbifeng on 2018/3/14.
 * Description: This class is use to get app icon , it has also considered Android O
 */

public class AppIconHelper {

    public static Bitmap getAppIcon(PackageManager mPackageManager, String packageName) {

        if (Build.VERSION.SDK_INT >= 26) {
            return AppIconHelperV26.getAppIcon(mPackageManager, packageName);
        }

        try {
            Drawable drawable = mPackageManager.getApplicationIcon(packageName);
            return ((BitmapDrawable) drawable).getBitmap();
        } catch (Exception e) {
            e.printStackTrace();
        }

        return null;
    }
}

AppIconHelperV26.java

package com.apusapps.booster.gm.launchpad.utils;

import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.drawable.AdaptiveIconDrawable;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.os.Build;
import android.support.annotation.RequiresApi;

/**
 * Created by wangbifeng on 2018/3/14.
 * Description: This class is used to get app icon on Android O
 */

class AppIconHelperV26 {
    @RequiresApi(api = Build.VERSION_CODES.O)
    public static Bitmap getAppIcon(PackageManager mPackageManager, String packageName) {

        try {
            Drawable drawable = mPackageManager.getApplicationIcon(packageName);

            if (drawable instanceof BitmapDrawable) {
                return ((BitmapDrawable) drawable).getBitmap();
            } else if (drawable instanceof AdaptiveIconDrawable) {
                Drawable backgroundDr = ((AdaptiveIconDrawable) drawable).getBackground();
                Drawable foregroundDr = ((AdaptiveIconDrawable) drawable).getForeground();

                Drawable[] drr = new Drawable[2];
                drr[0] = backgroundDr;
                drr[1] = foregroundDr;

                LayerDrawable layerDrawable = new LayerDrawable(drr);

                int width = layerDrawable.getIntrinsicWidth();
                int height = layerDrawable.getIntrinsicHeight();

                Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);

                Canvas canvas = new Canvas(bitmap);

                layerDrawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
                layerDrawable.draw(canvas);

                return bitmap;
            }
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }

        return null;
    }
}

然后再代码中这样使用就可以啦

Bitmap bitmap = AppIconHelper.getAppIcon(mContext.getPackageManager(), packageName);

如果文章当中有任何不正确的地方，还请广大读者纠正，非常感谢！