Android屏幕截图并保存截取屏幕的图片到指定文件

注意要添加权限：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

完整代码：

package zhangphil.test;

import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Environment;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.DisplayMetrics;
import android.view.View;
import android.widget.Toast;

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

public class JavaActivity extends AppCompatActivity {

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

        AppCompatActivity activity = this;

        findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "zhangphil.jpg");
                Bitmap bitmap = screenShot(activity);
                try {
                    if (!file.exists())
                        file.createNewFile();

                    boolean ret = save(bitmap, file, Bitmap.CompressFormat.JPEG, true);
                    if (ret) {
                        Toast.makeText(getApplicationContext(), "截图已保持至 " + file.getAbsolutePath(), Toast.LENGTH_SHORT).show();
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * 保存图片到文件File。
     *
     * @param src     源图片
     * @param file    要保存到的文件
     * @param format  格式
     * @param recycle 是否回收
     * @return true 成功 false 失败
     */
    public static boolean save(Bitmap src, File file, Bitmap.CompressFormat format, boolean recycle) {
        if (isEmptyBitmap(src))
            return false;

        OutputStream os;
        boolean ret = false;
        try {
            os = new BufferedOutputStream(new FileOutputStream(file));
            ret = src.compress(format, 100, os);
            if (recycle && !src.isRecycled())
                src.recycle();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return ret;
    }


    /**
     * 获取当前屏幕截图，不包含状态栏（Status Bar）。
     *
     * @param activity activity
     * @return Bitmap
     */
    public static Bitmap screenShot(Activity activity) {
        View view = activity.getWindow().getDecorView();
        view.setDrawingCacheEnabled(true);
        view.buildDrawingCache();
        Bitmap bmp = view.getDrawingCache();
        int statusBarHeight = getStatusBarHeight(activity);
        int width = (int) getDeviceDisplaySize(activity)[0];
        int height = (int) getDeviceDisplaySize(activity)[1];

        Bitmap ret = Bitmap.createBitmap(bmp, 0, statusBarHeight, width, height - statusBarHeight);
        view.destroyDrawingCache();

        return ret;
    }

    public static float[] getDeviceDisplaySize(Context context) {
        Resources resources = context.getResources();
        DisplayMetrics dm = resources.getDisplayMetrics();
        int width = dm.widthPixels;
        int height = dm.heightPixels;

        float[] size = new float[2];
        size[0] = width;
        size[1] = height;

        return size;
    }

    public static int getStatusBarHeight(Context context) {
        int height = 0;
        int resourceId = context.getResources().getIdentifier("status_bar_height", "dimen", "android");
        if (resourceId > 0) {
            height = context.getResources().getDimensionPixelSize(resourceId);
        }

        return height;
    }

    /**
     * Bitmap对象是否为空。
     */
    public static boolean isEmptyBitmap(Bitmap src) {
        return src == null || src.getWidth() == 0 || src.getHeight() == 0;
    }
}