DensityActivity.java revision 3b0146057889eaf6eb1a6ebc86553a95885f074f 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.example.android.apis.graphics;
18
19//Need the following import to get access to the app resources, since this
20//class is in a sub-package.
21import com.example.android.apis.R;
22
23import android.app.Activity;
24import android.app.Application;
25import android.os.Bundle;
26import android.graphics.BitmapFactory;
27import android.graphics.Bitmap;
28import android.graphics.Canvas;
29import android.graphics.drawable.BitmapDrawable;
30import android.graphics.drawable.Drawable;
31import android.widget.LinearLayout;
32import android.widget.TextView;
33import android.widget.ScrollView;
34import android.view.LayoutInflater;
35import android.view.View;
36import android.content.Context;
37import android.content.pm.ApplicationInfo;
38import android.content.pm.PackageManager;
39import android.util.DisplayMetrics;
40import android.util.Log;
41
42/**
43 * This activity demonstrates various ways density can cause the scaling of
44 * bitmaps and drawables.
45 */
46public class DensityActivity extends Activity {
47    @Override
48    protected void onCreate(Bundle savedInstanceState) {
49        super.onCreate(savedInstanceState);
50
51        final LayoutInflater li = (LayoutInflater)getSystemService(
52                LAYOUT_INFLATER_SERVICE);
53
54        this.setTitle(R.string.density_title);
55        LinearLayout root = new LinearLayout(this);
56        root.setOrientation(LinearLayout.VERTICAL);
57
58        LinearLayout layout = new LinearLayout(this);
59        addBitmapDrawable(layout, R.drawable.logo120dpi, true);
60        addBitmapDrawable(layout, R.drawable.logo160dpi, true);
61        addBitmapDrawable(layout, R.drawable.logo240dpi, true);
62        addLabelToRoot(root, "Prescaled bitmap in drawable");
63        addChildToRoot(root, layout);
64
65        layout = new LinearLayout(this);
66        addBitmapDrawable(layout, R.drawable.logo120dpi, false);
67        addBitmapDrawable(layout, R.drawable.logo160dpi, false);
68        addBitmapDrawable(layout, R.drawable.logo240dpi, false);
69        addLabelToRoot(root, "Autoscaled bitmap in drawable");
70        addChildToRoot(root, layout);
71
72        layout = new LinearLayout(this);
73        addResourceDrawable(layout, R.drawable.logo120dpi);
74        addResourceDrawable(layout, R.drawable.logo160dpi);
75        addResourceDrawable(layout, R.drawable.logo240dpi);
76        addLabelToRoot(root, "Prescaled resource drawable");
77        addChildToRoot(root, layout);
78
79        layout = (LinearLayout)li.inflate(R.layout.density_image_views, null);
80        addLabelToRoot(root, "Inflated layout");
81        addChildToRoot(root, layout);
82
83        layout = (LinearLayout)li.inflate(R.layout.density_styled_image_views, null);
84        addLabelToRoot(root, "Inflated styled layout");
85        addChildToRoot(root, layout);
86
87        layout = new LinearLayout(this);
88        addCanvasBitmap(layout, R.drawable.logo120dpi, true);
89        addCanvasBitmap(layout, R.drawable.logo160dpi, true);
90        addCanvasBitmap(layout, R.drawable.logo240dpi, true);
91        addLabelToRoot(root, "Prescaled bitmap");
92        addChildToRoot(root, layout);
93
94        layout = new LinearLayout(this);
95        addCanvasBitmap(layout, R.drawable.logo120dpi, false);
96        addCanvasBitmap(layout, R.drawable.logo160dpi, false);
97        addCanvasBitmap(layout, R.drawable.logo240dpi, false);
98        addLabelToRoot(root, "Autoscaled bitmap");
99        addChildToRoot(root, layout);
100
101        layout = new LinearLayout(this);
102        addResourceDrawable(layout, R.drawable.logonodpi120);
103        addResourceDrawable(layout, R.drawable.logonodpi160);
104        addResourceDrawable(layout, R.drawable.logonodpi240);
105        addLabelToRoot(root, "No-dpi resource drawable");
106        addChildToRoot(root, layout);
107
108        layout = new LinearLayout(this);
109        addNinePatchResourceDrawable(layout, R.drawable.smlnpatch120dpi);
110        addNinePatchResourceDrawable(layout, R.drawable.smlnpatch160dpi);
111        addNinePatchResourceDrawable(layout, R.drawable.smlnpatch240dpi);
112        addLabelToRoot(root, "Prescaled 9-patch resource drawable");
113        addChildToRoot(root, layout);
114
115        setContentView(scrollWrap(root));
116    }
117
118    private View scrollWrap(View view) {
119        ScrollView scroller = new ScrollView(this);
120        scroller.addView(view, new ScrollView.LayoutParams(ScrollView.LayoutParams.FILL_PARENT,
121                ScrollView.LayoutParams.FILL_PARENT));
122        return scroller;
123    }
124
125    private void addLabelToRoot(LinearLayout root, String text) {
126        TextView label = new TextView(this);
127        label.setText(text);
128        root.addView(label, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT,
129                LinearLayout.LayoutParams.WRAP_CONTENT));
130    }
131
132    private void addChildToRoot(LinearLayout root, LinearLayout layout) {
133        root.addView(layout, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT,
134                LinearLayout.LayoutParams.WRAP_CONTENT));
135    }
136
137    private void addBitmapDrawable(LinearLayout layout, int resource, boolean scale) {
138        Bitmap bitmap;
139        bitmap = loadAndPrintDpi(resource, scale);
140
141        View view = new View(this);
142
143        final BitmapDrawable d = new BitmapDrawable(getResources(), bitmap);
144        if (!scale) d.setTargetDensity(getResources().getDisplayMetrics());
145        view.setBackgroundDrawable(d);
146
147        view.setLayoutParams(new LinearLayout.LayoutParams(d.getIntrinsicWidth(),
148                d.getIntrinsicHeight()));
149        layout.addView(view);
150    }
151
152    private void addResourceDrawable(LinearLayout layout, int resource) {
153        View view = new View(this);
154
155        final Drawable d = getResources().getDrawable(resource);
156        view.setBackgroundDrawable(d);
157
158        view.setLayoutParams(new LinearLayout.LayoutParams(d.getIntrinsicWidth(),
159                d.getIntrinsicHeight()));
160        layout.addView(view);
161    }
162
163    private void addCanvasBitmap(LinearLayout layout, int resource, boolean scale) {
164        Bitmap bitmap;
165        bitmap = loadAndPrintDpi(resource, scale);
166
167        ScaledBitmapView view = new ScaledBitmapView(this, bitmap);
168
169        view.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
170                LinearLayout.LayoutParams.WRAP_CONTENT));
171        layout.addView(view);
172    }
173
174    private void addNinePatchResourceDrawable(LinearLayout layout, int resource) {
175        View view = new View(this);
176
177        final Drawable d = getResources().getDrawable(resource);
178        view.setBackgroundDrawable(d);
179
180        Log.i("foo", "9-patch #" + Integer.toHexString(resource)
181                + " w=" + d.getIntrinsicWidth() + " h=" + d.getIntrinsicHeight());
182        view.setLayoutParams(new LinearLayout.LayoutParams(
183                d.getIntrinsicWidth()*2, d.getIntrinsicHeight()*2));
184        layout.addView(view);
185    }
186
187    private Bitmap loadAndPrintDpi(int id, boolean scale) {
188        Bitmap bitmap;
189        if (scale) {
190            bitmap = BitmapFactory.decodeResource(getResources(), id);
191        } else {
192            BitmapFactory.Options opts = new BitmapFactory.Options();
193            opts.inScaled = false;
194            bitmap = BitmapFactory.decodeResource(getResources(), id, opts);
195        }
196        return bitmap;
197    }
198
199    private class ScaledBitmapView extends View {
200        private Bitmap mBitmap;
201
202        public ScaledBitmapView(Context context, Bitmap bitmap) {
203            super(context);
204            mBitmap = bitmap;
205        }
206
207        @Override
208        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
209            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
210            final DisplayMetrics metrics = getResources().getDisplayMetrics();
211            setMeasuredDimension(
212                    mBitmap.getScaledWidth(metrics),
213                    mBitmap.getScaledHeight(metrics));
214        }
215
216        @Override
217        protected void onDraw(Canvas canvas) {
218            super.onDraw(canvas);
219
220            canvas.drawBitmap(mBitmap, 0.0f, 0.0f, null);
221        }
222    }
223}
224