| /* |
| * 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.content.Context; |
| import android.graphics.*; |
| import android.os.Bundle; |
| import android.view.*; |
| |
| import java.io.InputStream; |
| |
| 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); |
| } |
| } |
| } |
| |