/* * Copyright (C) 2007 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package com.example.android.apis.graphics;import com.example.android.apis.R;import android.app.Activity;import android.content.Context;import android.graphics.*;import android.os.Bundle;import android.view.KeyEvent;import android.view.*;import java.io.InputStream;import java.io.ByteArrayOutputStream;public class AlphaBitmap extends GraphicsActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(new SampleView(this));    }        private static class SampleView extends View {        private Bitmap mBitmap;        private Bitmap mBitmap2;        private Bitmap mBitmap3;        private Shader mShader;                private static void drawIntoBitmap(Bitmap bm) {            float x = bm.getWidth();            float y = bm.getHeight();            Canvas c = new Canvas(bm);            Paint p = new Paint();            p.setAntiAlias(true);                        p.setAlpha(0x80);            c.drawCircle(x/2, y/2, x/2, p);                        p.setAlpha(0x30);            p.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));            p.setTextSize(60);            p.setTextAlign(Paint.Align.CENTER);            Paint.FontMetrics fm = p.getFontMetrics();            c.drawText("Alpha", x/2, (y-fm.ascent)/2, p);        }                public SampleView(Context context) {            super(context);            setFocusable(true);                        InputStream is = context.getResources().openRawResource(R.drawable.app_sample_code);            mBitmap = BitmapFactory.decodeStream(is);            mBitmap2 = mBitmap.extractAlpha();            mBitmap3 = Bitmap.createBitmap(200, 200, Bitmap.Config.ALPHA_8);            drawIntoBitmap(mBitmap3);                        mShader = new LinearGradient(0, 0, 100, 70, new int[] {                                         Color.RED, Color.GREEN, Color.BLUE },                                         null, Shader.TileMode.MIRROR);        }                @Override protected void onDraw(Canvas canvas) {            canvas.drawColor(Color.WHITE);            Paint p = new Paint();            float y = 10;                        p.setColor(Color.RED);            canvas.drawBitmap(mBitmap, 10, y, p);            y += mBitmap.getHeight() + 10;            canvas.drawBitmap(mBitmap2, 10, y, p);            y += mBitmap2.getHeight() + 10;            p.setShader(mShader);            canvas.drawBitmap(mBitmap3, 10, y, p);        }    }}