ImageUtils.java

package xyz.yhsj.yhutils.io;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.TransitionDrawable;
import android.support.annotation.DrawableRes;
import android.widget.ImageView;

public class ImageUtils {

    /**
     * 渐变显示图片
     *
     * @param context
     * @param imageView
     * @param bitmap
     */
    @SuppressWarnings("deprecation")
    public static void setImageBitmap(Context context, ImageView imageView,
                                      Bitmap bitmap) {
        // Use TransitionDrawable to fade in.
        final TransitionDrawable td = new TransitionDrawable(new Drawable[]{
                new ColorDrawable(context.getResources().getColor(android.R.color.transparent)),
                new BitmapDrawable(context.getResources(), bitmap)});
        // noinspection deprecation
        // imageView.setBackgroundDrawable(imageView.getDrawable());
        imageView.setImageDrawable(td);
        td.startTransition(200);
    }

    /**
     * 保存图片
     *
     * @param filePath 文件路径+文件名
     * @param bitmap  文件内容
     * @throws IOException
     */
    public static void saveAsJPEG(Bitmap bitmap, String filePath)
            throws IOException {
        FileOutputStream fos = null;

        try {
            File file = new File(filePath);
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdirs();
            }
            fos = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
            fos.flush();
        } finally {
            if (fos != null) {
                fos.close();
            }
        }
    }

    /**
     * 保存图片
     *
     * @param filePath 文件路径+文件名
     * @param bitmap  文件内容
     * @throws IOException
     */
    public static void saveAsPNG(Bitmap bitmap, String filePath)
            throws IOException {
        FileOutputStream fos = null;

        try {
            File file = new File(filePath);
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdirs();
            }
            fos = new FileOutputStream(file);
            bitmap.compress(Bitmap.CompressFormat.PNG, 100, fos);
            fos.flush();
        } finally {
            if (fos != null) {
                fos.close();
            }
        }
    }
}