Home | History | Annotate | Download | only in graphics 
      1 /*
      2  * Copyright (C) 2009 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 import com.example.android.apis.R;
     20 
     21 import android.app.Activity;
     22 import android.content.Context;
     23 import android.graphics.*;
     24 import android.graphics.drawable.*;
     25 import android.os.Bundle;
     26 import android.view.*;
     27 
     28 public class ColorFilters extends GraphicsActivity {
     29 
     30     @Override
     31     protected void onCreate(Bundle savedInstanceState) {
     32         super.onCreate(savedInstanceState);
     33         setContentView(new SampleView(this));
     34 
     35     }
     36 
     37     private static class SampleView extends View {
     38         private Activity mActivity;
     39         private Drawable mDrawable;
     40         private Drawable[] mDrawables;
     41         private Paint mPaint;
     42         private Paint mPaint2;
     43         private float mPaintTextOffset;
     44         private int[] mColors;
     45         private PorterDuff.Mode[] mModes;
     46         private int mModeIndex;
     47 
     48         private static void addToTheRight(Drawable curr, Drawable prev) {
     49             Rect r = prev.getBounds();
     50             int x = r.right + 12;
     51             int center = (r.top + r.bottom) >> 1;
     52             int h = curr.getIntrinsicHeight();
     53             int y = center - (h >> 1);
     54 
     55             curr.setBounds(x, y, x + curr.getIntrinsicWidth(), y + h);
     56         }
     57 
     58         public SampleView(Activity activity) {
     59             super(activity);
     60             mActivity = activity;
     61             Context context = activity;
     62             setFocusable(true);
     63 
     64             mDrawable = context.getResources().getDrawable(R.drawable.btn_default_normal);
     65             mDrawable.setBounds(0, 0, 150, 48);
     66             mDrawable.setDither(true);
     67 
     68             int[] resIDs = new int[] {
     69                 R.drawable.btn_circle_normal,
     70                 R.drawable.btn_check_off,
     71                 R.drawable.btn_check_on
     72             };
     73             mDrawables = new Drawable[resIDs.length];
     74             Drawable prev = mDrawable;
     75             for (int i = 0; i < resIDs.length; i++) {
     76                 mDrawables[i] = context.getResources().getDrawable(resIDs[i]);
     77                 mDrawables[i].setDither(true);
     78                 addToTheRight(mDrawables[i], prev);
     79                 prev = mDrawables[i];
     80             }
     81 
     82             mPaint = new Paint();
     83             mPaint.setAntiAlias(true);
     84             mPaint.setTextSize(16);
     85             mPaint.setTextAlign(Paint.Align.CENTER);
     86 
     87             mPaint2 = new Paint(mPaint);
     88             mPaint2.setAlpha(64);
     89 
     90             Paint.FontMetrics fm = mPaint.getFontMetrics();
     91             mPaintTextOffset = (fm.descent + fm.ascent) * 0.5f;
     92 
     93             mColors = new int[] {
     94                 0,
     95                 0xCC0000FF,
     96                 0x880000FF,
     97                 0x440000FF,
     98                 0xFFCCCCFF,
     99                 0xFF8888FF,
    100                 0xFF4444FF,
    101             };
    102 
    103             mModes = new PorterDuff.Mode[] {
    104                 PorterDuff.Mode.SRC_ATOP,
    105                 PorterDuff.Mode.MULTIPLY,
    106             };
    107             mModeIndex = 0;
    108 
    109             updateTitle();
    110         }
    111 
    112         private void swapPaintColors() {
    113             if (mPaint.getColor() == 0xFF000000) {
    114                 mPaint.setColor(0xFFFFFFFF);
    115                 mPaint2.setColor(0xFF000000);
    116             } else {
    117                 mPaint.setColor(0xFF000000);
    118                 mPaint2.setColor(0xFFFFFFFF);
    119             }
    120             mPaint2.setAlpha(64);
    121         }
    122 
    123         private void updateTitle() {
    124             mActivity.setTitle(mModes[mModeIndex].toString());
    125         }
    126 
    127         private void drawSample(Canvas canvas, ColorFilter filter) {
    128             Rect r = mDrawable.getBounds();
    129             float x = (r.left + r.right) * 0.5f;
    130             float y = (r.top + r.bottom) * 0.5f - mPaintTextOffset;
    131 
    132             mDrawable.setColorFilter(filter);
    133             mDrawable.draw(canvas);
    134             canvas.drawText("Label", x+1, y+1, mPaint2);
    135             canvas.drawText("Label", x, y, mPaint);
    136 
    137             for (Drawable dr : mDrawables) {
    138                 dr.setColorFilter(filter);
    139                 dr.draw(canvas);
    140             }
    141         }
    142 
    143         @Override protected void onDraw(Canvas canvas) {
    144             canvas.drawColor(0xFFCCCCCC);
    145 
    146             canvas.translate(8, 12);
    147             for (int color : mColors) {
    148                 ColorFilter filter;
    149                 if (color == 0) {
    150                     filter = null;
    151                 } else {
    152                     filter = new PorterDuffColorFilter(color,
    153                                                        mModes[mModeIndex]);
    154                 }
    155                 drawSample(canvas, filter);
    156                 canvas.translate(0, 55);
    157             }
    158         }
    159 
    160         @Override
    161         public boolean onTouchEvent(MotionEvent event) {
    162             switch (event.getAction()) {
    163                 case MotionEvent.ACTION_DOWN:
    164                     break;
    165                 case MotionEvent.ACTION_MOVE:
    166                     break;
    167                 case MotionEvent.ACTION_UP:
    168                     // update mode every other time we change paint colors
    169                     if (mPaint.getColor() == 0xFFFFFFFF) {
    170                         mModeIndex = (mModeIndex + 1) % mModes.length;
    171                         updateTitle();
    172                     }
    173                     swapPaintColors();
    174                     invalidate();
    175                     break;
    176             }
    177             return true;
    178         }
    179     }
    180 }
    181