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/*
* 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);
}
}
}
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