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      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 
     17 package 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.
     21 import com.example.android.apis.R;
     22 
     23 import android.app.Activity;
     24 import android.os.Bundle;
     25 import android.graphics.BitmapFactory;
     26 import android.graphics.Bitmap;
     27 import android.graphics.Canvas;
     28 import android.graphics.drawable.BitmapDrawable;
     29 import android.graphics.drawable.Drawable;
     30 import android.widget.LinearLayout;
     31 import android.widget.TextView;
     32 import android.widget.ScrollView;
     33 import android.view.LayoutInflater;
     34 import android.view.View;
     35 import android.content.Context;
     36 import android.util.DisplayMetrics;
     37 import android.util.Log;
     38 
     39 /**
     40  * This activity demonstrates various ways density can cause the scaling of
     41  * bitmaps and drawables.
     42  */
     43 public class DensityActivity extends Activity {
     44     @Override
     45     protected void onCreate(Bundle savedInstanceState) {
     46         super.onCreate(savedInstanceState);
     47 
     48         final LayoutInflater li = (LayoutInflater)getSystemService(
     49                 LAYOUT_INFLATER_SERVICE);
     50 
     51         this.setTitle(R.string.density_title);
     52         LinearLayout root = new LinearLayout(this);
     53         root.setOrientation(LinearLayout.VERTICAL);
     54 
     55         LinearLayout layout = new LinearLayout(this);
     56         addBitmapDrawable(layout, R.drawable.logo120dpi, true);
     57         addBitmapDrawable(layout, R.drawable.logo160dpi, true);
     58         addBitmapDrawable(layout, R.drawable.logo240dpi, true);
     59         addLabelToRoot(root, "Prescaled bitmap in drawable");
     60         addChildToRoot(root, layout);
     61 
     62         layout = new LinearLayout(this);
     63         addBitmapDrawable(layout, R.drawable.logo120dpi, false);
     64         addBitmapDrawable(layout, R.drawable.logo160dpi, false);
     65         addBitmapDrawable(layout, R.drawable.logo240dpi, false);
     66         addLabelToRoot(root, "Autoscaled bitmap in drawable");
     67         addChildToRoot(root, layout);
     68 
     69         layout = new LinearLayout(this);
     70         addResourceDrawable(layout, R.drawable.logo120dpi);
     71         addResourceDrawable(layout, R.drawable.logo160dpi);
     72         addResourceDrawable(layout, R.drawable.logo240dpi);
     73         addLabelToRoot(root, "Prescaled resource drawable");
     74         addChildToRoot(root, layout);
     75 
     76         layout = (LinearLayout)li.inflate(R.layout.density_image_views, null);
     77         addLabelToRoot(root, "Inflated layout");
     78         addChildToRoot(root, layout);
     79 
     80         layout = (LinearLayout)li.inflate(R.layout.density_styled_image_views, null);
     81         addLabelToRoot(root, "Inflated styled layout");
     82         addChildToRoot(root, layout);
     83 
     84         layout = new LinearLayout(this);
     85         addCanvasBitmap(layout, R.drawable.logo120dpi, true);
     86         addCanvasBitmap(layout, R.drawable.logo160dpi, true);
     87         addCanvasBitmap(layout, R.drawable.logo240dpi, true);
     88         addLabelToRoot(root, "Prescaled bitmap");
     89         addChildToRoot(root, layout);
     90 
     91         layout = new LinearLayout(this);
     92         addCanvasBitmap(layout, R.drawable.logo120dpi, false);
     93         addCanvasBitmap(layout, R.drawable.logo160dpi, false);
     94         addCanvasBitmap(layout, R.drawable.logo240dpi, false);
     95         addLabelToRoot(root, "Autoscaled bitmap");
     96         addChildToRoot(root, layout);
     97 
     98         layout = new LinearLayout(this);
     99         addResourceDrawable(layout, R.drawable.logonodpi120);
    100         addResourceDrawable(layout, R.drawable.logonodpi160);
    101         addResourceDrawable(layout, R.drawable.logonodpi240);
    102         addLabelToRoot(root, "No-dpi resource drawable");
    103         addChildToRoot(root, layout);
    104 
    105         layout = new LinearLayout(this);
    106         addNinePatchResourceDrawable(layout, R.drawable.smlnpatch120dpi);
    107         addNinePatchResourceDrawable(layout, R.drawable.smlnpatch160dpi);
    108         addNinePatchResourceDrawable(layout, R.drawable.smlnpatch240dpi);
    109         addLabelToRoot(root, "Prescaled 9-patch resource drawable");
    110         addChildToRoot(root, layout);
    111 
    112         setContentView(scrollWrap(root));
    113     }
    114 
    115     private View scrollWrap(View view) {
    116         ScrollView scroller = new ScrollView(this);
    117         scroller.addView(view, new ScrollView.LayoutParams(ScrollView.LayoutParams.MATCH_PARENT,
    118                 ScrollView.LayoutParams.MATCH_PARENT));
    119         return scroller;
    120     }
    121 
    122     private void addLabelToRoot(LinearLayout root, String text) {
    123         TextView label = new TextView(this);
    124         label.setText(text);
    125         root.addView(label, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
    126                 LinearLayout.LayoutParams.WRAP_CONTENT));
    127     }
    128 
    129     private void addChildToRoot(LinearLayout root, LinearLayout layout) {
    130         root.addView(layout, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
    131                 LinearLayout.LayoutParams.WRAP_CONTENT));
    132     }
    133 
    134     private void addBitmapDrawable(LinearLayout layout, int resource, boolean scale) {
    135         Bitmap bitmap;
    136         bitmap = loadAndPrintDpi(resource, scale);
    137 
    138         View view = new View(this);
    139 
    140         final BitmapDrawable d = new BitmapDrawable(getResources(), bitmap);
    141         if (!scale) d.setTargetDensity(getResources().getDisplayMetrics());
    142         view.setBackgroundDrawable(d);
    143 
    144         view.setLayoutParams(new LinearLayout.LayoutParams(d.getIntrinsicWidth(),
    145                 d.getIntrinsicHeight()));
    146         layout.addView(view);
    147     }
    148 
    149     private void addResourceDrawable(LinearLayout layout, int resource) {
    150         View view = new View(this);
    151 
    152         final Drawable d = getResources().getDrawable(resource);
    153         view.setBackgroundDrawable(d);
    154 
    155         view.setLayoutParams(new LinearLayout.LayoutParams(d.getIntrinsicWidth(),
    156                 d.getIntrinsicHeight()));
    157         layout.addView(view);
    158     }
    159 
    160     private void addCanvasBitmap(LinearLayout layout, int resource, boolean scale) {
    161         Bitmap bitmap;
    162         bitmap = loadAndPrintDpi(resource, scale);
    163 
    164         ScaledBitmapView view = new ScaledBitmapView(this, bitmap);
    165 
    166         view.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
    167                 LinearLayout.LayoutParams.WRAP_CONTENT));
    168         layout.addView(view);
    169     }
    170 
    171     private void addNinePatchResourceDrawable(LinearLayout layout, int resource) {
    172         View view = new View(this);
    173 
    174         final Drawable d = getResources().getDrawable(resource);
    175         view.setBackgroundDrawable(d);
    176 
    177         Log.i("foo", "9-patch #" + Integer.toHexString(resource)
    178                 + " w=" + d.getIntrinsicWidth() + " h=" + d.getIntrinsicHeight());
    179         view.setLayoutParams(new LinearLayout.LayoutParams(
    180                 d.getIntrinsicWidth()*2, d.getIntrinsicHeight()*2));
    181         layout.addView(view);
    182     }
    183 
    184     private Bitmap loadAndPrintDpi(int id, boolean scale) {
    185         Bitmap bitmap;
    186         if (scale) {
    187             bitmap = BitmapFactory.decodeResource(getResources(), id);
    188         } else {
    189             BitmapFactory.Options opts = new BitmapFactory.Options();
    190             opts.inScaled = false;
    191             bitmap = BitmapFactory.decodeResource(getResources(), id, opts);
    192         }
    193         return bitmap;
    194     }
    195 
    196     private class ScaledBitmapView extends View {
    197         private Bitmap mBitmap;
    198 
    199         public ScaledBitmapView(Context context, Bitmap bitmap) {
    200             super(context);
    201             mBitmap = bitmap;
    202         }
    203 
    204         @Override
    205         protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    206             super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    207             final DisplayMetrics metrics = getResources().getDisplayMetrics();
    208             setMeasuredDimension(
    209                     mBitmap.getScaledWidth(metrics),
    210                     mBitmap.getScaledHeight(metrics));
    211         }
    212 
    213         @Override
    214         protected void onDraw(Canvas canvas) {
    215             super.onDraw(canvas);
    216 
    217             canvas.drawBitmap(mBitmap, 0.0f, 0.0f, null);
    218         }
    219     }
    220 }
    221