Android開發：Bitmap和canvas的應用

1. 畫虛線<div>SET_WALLPAPER </div>

2. public class Canvas extends Activity implements OnTouchListener {
3. /** Called when the activity is first created. */
4. @Override
5. public void onCreate(Bundle savedInstanceState) {
6. super.onCreate(savedInstanceState);
7. this.requestWindowFeature(Window.FEATURE_NO_TITLE);// 去掉標題欄
8. this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
9. WindowManager.LayoutParams.FLAG_FULLSCREEN);// 去掉信息欄
10. setContentView(R.layout.main);
12. iv = new ImageView(this);
13. bitmap = Bitmap.createBitmap(800, 480, Bitmap.Config.ARGB_8888);
14. iv.setImageBitmap(bitmap);
16. LinearLayout ll = (LinearLayout) findViewById(R.id.ll);
17. ll.addView(iv, new LayoutParams(800, 480));
19. ll.setOnTouchListener(this);
21. }
22. private android.graphics.Canvas myCanvas;
23. private Bitmap bitmap;
24. private Paint myPaint;
25. private ImageView iv;
26. private float left;
27. private float top;
28. @Override
29. public boolean onTouch(View v, MotionEvent event) {
30. switch (event.getAction()) {
31. case MotionEvent.ACTION_DOWN:
32. myCanvas = new android.graphics.Canvas(bitmap);
33. myPaint = new Paint();
34. // myPaint.setAntiAlias(true);//抗鋸齒
35. //
36. // RectF oval = new RectF(0, 0, 200, 200);
37. // myPaint.setColor(Color.DKGRAY);
38. // myCanvas.drawArc(oval, 0, 360, true, myPaint);
39. //
40. // myPaint.setColor(Color.LTGRAY);
41. //
42. // myCanvas.drawArc(oval, 0, 320, true, myPaint);
45. // RectF eyes = new RectF(100, 20, 130, 50);
46. // myPaint.setColor(Color.RED);
47. // myCanvas.drawArc(eyes, 0, 360, true, myPaint);
48. // myCanvas.drawCircle(200, 300, 100, myPaint);
50. System.out.println("======================");
51. iv.setImageBitmap(bitmap);
53. left = event.getX();
54. top = event.getY();
56. break;
58. case MotionEvent.ACTION_MOVE:
59. // myCanvas.drawPoint(event.getX(), event.getY(), myPaint);
60. // myPaint.setTypeface(Typeface.createFromFile("/sdcard/stxingka.ttf"));
61. // myPaint.setTextSize(50);
62. // myCanvas.drawText("Hello World!", event.getX(), event.getY(), myPaint);
64. PathEffect pathEffect = new DashPathEffect(
65. new float[] { 5, 5, 5, 5 }, 1);
66. myPaint.setColor(Color.GREEN);
67. myPaint.setPathEffect(pathEffect);
68. myPaint.setStyle(Style.STROKE);
69. myPaint.setStrokeWidth(3);
70. myCanvas.drawARGB(255, 20, 30, 41);
71. myCanvas.drawRect(new RectF(left, top, event.getX(), event.getY()),myPaint);
72. iv.setImageBitmap(bitmap);
73. break;
74. case MotionEvent.ACTION_UP:
75. break;
76. }
77. return true;
78. }

一個讓Gridview項移動的例子:

1. public class Utils {
2. public static int[] image = { R.drawable.mb5u1_mb5ucom, R.drawable.mb5u2_mb5ucom,
3. R.drawable.mb5u3_mb5ucom, R.drawable.mb5u4_mb5ucom,
4. R.drawable.mb5u5_mb5ucom, R.drawable.mb5u6_mb5ucom,
5. R.drawable.mb5u7_mb5ucom, R.drawable.mb5u8_mb5ucom,
6. R.drawable.mb5u9_mb5ucom, R.drawable.mb5u10_mb5ucom,
7. R.drawable.mb5u11_mb5ucom, R.drawable.mb5u12_mb5ucom,
8. R.drawable.mb5u13_mb5ucom, R.drawable.mb5u14_mb5ucom,
9. R.drawable.mb5u15_mb5ucom, R.drawable.mb5u16_mb5ucom,
10. R.drawable.mb5u17_mb5ucom, R.drawable.mb5u18_mb5ucom,
11. R.drawable.mb5u19_mb5ucom, R.drawable.mb5u20_mb5ucom,
12. R.drawable.mb5u21_mb5ucom, R.drawable.mb5u22_mb5ucom,
13. R.drawable.mb5u23_mb5ucom, R.drawable.mb5u24_mb5ucom,
14. R.drawable.mb5u25_mb5ucom, R.drawable.mb5u26_mb5ucom,
15. R.drawable.mb5u27_mb5ucom, R.drawable.mb5u28_mb5ucom,
16. R.drawable.mb5u29_mb5ucom, R.drawable.mb5u30_mb5ucom,
17. R.drawable.mb5u31_mb5ucom, R.drawable.mb5u32_mb5ucom,
18. R.drawable.mb5u33_mb5ucom, R.drawable.mb5u34_mb5ucom,
19. R.drawable.mb5u35_mb5ucom, R.drawable.mb5u36_mb5ucom,
20. R.drawable.mb5u37_mb5ucom, R.drawable.mb5u38_mb5ucom,
21. R.drawable.mb5u39_mb5ucom, R.drawable.mb5u40_mb5ucom,
22. R.drawable.mb5u41_mb5ucom, R.drawable.mb5u42_mb5ucom,
23. R.drawable.mb5u43_mb5ucom, R.drawable.mb5u44_mb5ucom };
25. public static ArrayList<Map<String, Object>> getData() {
26. ArrayList<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
27. for (int i = 0; i < 23; i++) {
28. Map<String, Object> map = new HashMap<String, Object>();
29. map.put("img", image[i]);
30. list.add(map);
31. }
32. return list;
33. }

正式綁定

1. public class MyGridViewDemo extends Activity implements OnTouchListener {
3. private RelativeLayout myRl;
4. private GridView myGridView;
5. private ArrayList<Map<String, Object>> mArray;
6. private MyAdapter adapter;
7. private int mDragViewX;
8. private int mDragViewY;
10. @Override
11. public void onCreate(Bundle savedInstanceState) {
12. super.onCreate(savedInstanceState);
14. this.requestWindowFeature(Window.FEATURE_NO_TITLE);// 去掉標題欄
15. this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
16. WindowManager.LayoutParams.FLAG_FULLSCREEN);// 去掉信息欄
18. setContentView(R.layout.main);
19. myRl = (RelativeLayout) findViewById(R.id.ll);
20. myGridView = new GridView(this);
21. mArray = Utils.getData();
22. System.out.println(mArray.size());
23. adapter = new MyAdapter(this, myGridView.getId(), mArray);
24. myGridView.setAdapter(adapter);
25. // GridView的列數
26. myGridView.setNumColumns(5);
28. myRl.addView(myGridView);
30. myGridView.setOnTouchListener(this);
32. }
34. class MyAdapter extends ArrayAdapter<Map<String, Object>> {
36. public MyAdapter(Context context, int textViewResourceId,
37. List<Map<String, Object>> objects) {
38. super(context, textViewResourceId, objects);
39. }
41. public ArrayList<Map<String, Object>> getList() {
42. return mArray;
43. }
45. public View getView(int position, View convertView, ViewGroup parent) {
46. View row = convertView;
47. if (row == null) {
48. LayoutInflater inflater = getLayoutInflater();
50. row = (View) inflater.inflate(R.layout.mygrid_item, null);
51. }
52. ImageView imageView = (ImageView) row.findViewById(R.id.img);
54. imageView.setImageResource(Integer.valueOf(mArray.get(position)
55. .get("img").toString()));
57. if (from == position) {
58. imageView.setVisibility(View.INVISIBLE);
59. } else if (View.INVISIBLE == imageView.getVisibility()) {
60. imageView.setVisibility(View.VISIBLE);
61. }
64. Log.i("ivan", "position =" + position + "aniFrom =" + aniFrom
65. + "aniTo" + aniTo);
66. Animation ani = null;
67. if (position > aniTo && position <= aniFrom) {
68. if (position % 5 == 0) {
69. ani = new TranslateAnimation(355, 0, -85, 0);
70. } else {
71. ani = new TranslateAnimation(-60, 0, 0, 0);
72. }
73. } else if (position < aniTo && position >= aniFrom) {
74. if (position % 5 == 4) {
75. ani = new TranslateAnimation(-355, 0, 85, 0);
76. } else {
77. ani = new TranslateAnimation(60, 0, 0, 0);
78. }
79. }
80. if (ani != null) {
81. ani.setAnimationListener(new AnimationListener() {
83. @Override
84. public void onAnimationStart(Animation animation) {
85. // TODO Auto-generated method stub
86. onAnimation = true;
87. }
88. @Override
89. public void onAnimationRepeat(Animation animation) {
90. // TODO Auto-generated method stub
91. }
92. @Override
93. public void onAnimationEnd(Animation animation) {
94. // TODO Auto-generated method stub
95. onAnimation = false;
96. }
97. });
98. ani.setDuration(500);
99. imageView.setAnimation(ani);
100. }
102. return imageView;
103. }
105. }
106. private boolean onAnimation = false;
107. private int from = -1;
108. private int to = -1;
109. private int aniTo;
110. private int aniFrom;
112. @Override
113. public boolean onTouch(View v, MotionEvent event) {
115. int x = (int) event.getX();
116. int y = (int) event.getY();
117. int position = myGridView.pointToPosition(x, y);
119. switch (event.getAction()) {
120. case MotionEvent.ACTION_DOWN:
122. // 如果沒有點擊到圖片直接break
123. System.out.println("position =" + position);
124. if (position == -1) {
125. break;
126. }
128. // 獲取到點擊的View
129. View tempView = myGridView.getChildAt(position
130. - myGridView.getFirstVisiblePosition());
131. System.out.println("tempView =" + tempView);
132. if (tempView == null) {
133. break;
134. }
135. // 開啟View的緩存
136. tempView.setDrawingCacheEnabled(true);
137. // tempView.getTop()獲取到tempView自身的位置，因為按下的時候應該顯示的位置和他自身的位置相同
138. // tempView.getLeft() 同理
139. startDragging(tempView.getDrawingCache(), tempView.getTop(),
140. tempView.getLeft());
142. // 獲取點擊的位置距所點擊圖片頂部的距離mDragViewX，mDragViewY
143. mDragViewX = x - tempView.getLeft();
144. mDragViewY = y - tempView.getTop();
146. from = position;
147. tempView.setVisibility(View.INVISIBLE);
148. break;
149. case MotionEvent.ACTION_MOVE:
150. if (myDragView != null) {
152. RelativeLayout.LayoutParams rllp = (LayoutParams) myDragView
153. .getLayoutParams();
154. rllp.leftMargin = x - mDragViewX;
155. rllp.topMargin = y - mDragViewY;
156. myDragView.setLayoutParams(rllp);
157. }
158. if (position != -1) {
159. to = position;
160. }
161. Log.i("ivan", "form=" + from);
162. if (from != to && from != -1 && to != -1 &&!onAnimation) {
164. aniFrom = from;
165. aniTo = to;
166. Map<String, Object> temp = adapter.getItem(from);
167. adapter.remove(temp);
168. adapter.insert(temp, to);
170. from = to;
172. }
174. break;
176. case MotionEvent.ACTION_UP:
177. if (myDragView != null) {
178. // 把myDragView 從RelativeLayout中刪除
179. myRl.removeView(myDragView);
180. }
181. // 獲取到松手位置的圖片讓其顯示
182. View end = myGridView.getChildAt(from
183. - myGridView.getFirstVisiblePosition());
184. if (end != null) {
185. end.setVisibility(View.VISIBLE);
186. }
188. from = -1;
189. to = -1;
190. break;
192. }
194. return true;
195. }
197. private ImageView myDragView;
199. private void startDragging(Bitmap tempBitmap, int top, int left) {
201. ImageView iv = new ImageView(getApplication());
202. RelativeLayout.LayoutParams rllp = new RelativeLayout.LayoutParams(-2,
203. -2);
205. rllp.leftMargin = left;
206. rllp.topMargin = top;
207. iv.setImageBitmap(tempBitmap);
208. // 測試方法看iv是否有值 作用是讓此View填充全屏
209. // setContentView(iv);
210. myDragView = iv;
212. myRl.addView(myDragView, rllp);
213. // 兩種寫法一樣
214. // mDragView.setLayoutParams(rllp);
215. // rl.addView(mDragView);
217. }

---------------------------------------------

dragwindow 圖片拖動

1. public class DragwindowActivity extends Activity {
2. /** Called when the activity is first created. */
3. @Override
4. public void onCreate(Bundle savedInstanceState) {
5. super.onCreate(savedInstanceState);
6. //setContentView(R.layout.main);
8. //設置窗體的屬性
9. WindowManager.LayoutParams params = new LayoutParams();
10. params.height = WindowManager.LayoutParams.FILL_PARENT;
11. params.width = WindowManager.LayoutParams.FILL_PARENT;
12. params.format = PixelFormat.TRANSLUCENT;
13. DisplayMetrics dm = getResources().getDisplayMetrics();
14. final int screenWidth = dm.widthPixels;
15. final int screenHeight = dm.heightPixels-50; //拖動窗體內的范圍
17. //把要拖動view布局文件孵化成view
18. LayoutInflater inflater = LayoutInflater.from(this);
19. View view = inflater.inflate(R.layout.main, null);
20. ImageButton button = (ImageButton) view.findViewById(R.id.ib_tt);
21. button.setOnTouchListener(new OnTouchListener() {
22. int lastX,lastY; //焦點
23. @Override
24. public boolean onTouch(View v, MotionEvent event) {
25. int me = event.getAction();
26. Log.i("TAG", "Touch:"+me); //按下是0,拖動是2,彈起是1;
27. switch(me){
28. case MotionEvent.ACTION_DOWN:
29. lastX = (int) event.getRawX();
30. lastY = (int) event.getRawY();
31. Log.i("TAG", "down x="+lastX+" ,y="+lastY);
32. break;
33. case MotionEvent.ACTION_MOVE:
34. int dx = (int) event.getRawX()-lastX;
35. int dy = (int) event.getRawY()-lastY;
36. Log.i("TAG", "d x="+dx+" ,d y="+dy); //拖動的坐標
37. //拖動移位後的坐標
38. int left = v.getLeft() + dx;
39. int top = v.getTop() + dy;
40. int right = v.getRight() + dx;
41. int bottom = v.getBottom() + dy;
42. if(left<0){
43. left = 0;
44. right=left+v.getWidth();
45. }
46. if(right>screenWidth){
47. right=screenWidth;
48. left = right-v.getWidth();
49. }
50. if(top<0){
51. top=0;
52. bottom = top+v.getHeight();
53. }
54. if(bottom>screenHeight){
55. bottom = screenHeight;
56. top = bottom - v.getHeight();
57. }
58. v.layout(left, top, right, bottom);
59. lastX = (int) event.getRawX();
60. lastY = (int) event.getRawY();
61. break;
62. case MotionEvent.ACTION_UP:
63. break;
64. }
65. return false;
66. }
67. });
68. WindowManager manager = (WindowManager) getSystemService(WINDOW_SERVICE);
69. manager.addView(view, params);
70. }

----------------------讀取相冊--畫圖保存

1. ImageView iv1;
2. Canvas canvas ;
3. Bitmap alteredBitmap;
4. /** Called when the activity is first created. */
5. @Override
6. public void onCreate(Bundle savedInstanceState) {
7. super.onCreate(savedInstanceState);
8. setContentView(R.layout.main);
9. iv1 =(ImageView) findViewById(R.id.iv1);
10. iv1.setOnTouchListener(this);
11. }
12. public void selectImage(View view) {
13. Intent intent = new Intent(Intent.ACTION_PICK);
14. intent.setType("image/*");
15. startActivityForResult(intent, 200);
16. }
17. public void saveImage(View view){
18. try {
19. Uri uri = getContentResolver().insert(Media.EXTERNAL_CONTENT_URI, new ContentValues());
20. OutputStream os = getContentResolver().openOutputStream(uri);
21. Boolean result = alteredBitmap.compress(CompressFormat.JPEG, 50, os);
22. if(result){
23. Toast.makeText(this, "保存成功", 1).show();
24. Intent intent = new Intent(Intent.ACTION_MEDIA_MOUNTED,Uri.parse("file://"+Environment.getExternalStorageDirectory()));
25. sendBroadcast(intent);
26. }else{
27. Toast.makeText(this, "保存失敗", 1).show();
28. }
29. } catch (FileNotFoundException e) {
30. e.printStackTrace();
31. }
32. }
33. @Override
34. protected void onActivityResult(int requestCode, int resultCode, Intent data) {
35. super.onActivityResult(requestCode, resultCode, data);
36. if (requestCode == 200) {
37. Uri uri = data.getData();
38. try {
39. // InputStream is =getContentResolver().openInputStream(uri);
40. //得到屏幕大小
41. Display currentDisplay = getWindowManager().getDefaultDisplay();
42. int dw = currentDisplay.getWidth();
43. int dh = currentDisplay.getHeight();
45. System.out.println(dw+"--"+dh);
46. BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();
47. // 如果設置了injustDecodeBounds這個屬性,不會真的解析bitmap,只返回bitmap的寬高和圖片屬性
48. bmpFactoryOptions.inJustDecodeBounds = true;
50. Bitmap bmp = BitmapFactory.decodeFile("/sdcard/066.JPG",
51. bmpFactoryOptions); //參數傳入只為得到bmp圖屬性 ，再縮小
52. int heightRatio = (int) Math.ceil(bmpFactoryOptions.outHeight
53. / (float) dh);
54. int widthRatio = (int) Math.ceil(bmpFactoryOptions.outWidth
55. / (float) dw);
57. // 判斷是否要進行縮放
58. if (heightRatio > 1 && widthRatio > 1) {
59. if (heightRatio > widthRatio) {
60. // 高度變化大,按高度縮放
61. bmpFactoryOptions.inSampleSize = heightRatio;
62. } else {
63. // 寬度變化大,按寬度縮放
64. bmpFactoryOptions.inSampleSize = widthRatio;
65. }
66. }
67. // 把inJustDecodeBounds設置為false,這樣才會真正的decode這個位圖
68. bmpFactoryOptions.inJustDecodeBounds = false;
69. //得到新圖片流
70. InputStream newis = getContentResolver().openInputStream(uri);
71. bmp = BitmapFactory.decodeStream(newis, null, bmpFactoryOptions);
72. // 創建一個bitmap的拷貝
73. // 創建了一個空的bitmap ，用原來的參數填充
74. alteredBitmap = Bitmap.createBitmap(bmp.getWidth(),
75. bmp.getHeight(), bmp.getConfig());
76. // 創建一個畫布
77. canvas = new Canvas(alteredBitmap);
78. // 創建一個畫筆
79. Paint paint = new Paint();
80. Matrix matrix = new Matrix();
81. canvas.drawBitmap(bmp, matrix, paint);
82. iv1.setImageBitmap(alteredBitmap);
83. } catch (FileNotFoundException e) {
84. e.printStackTrace();
85. }
86. }
87. }
88. float downx = 0;
89. float downy = 0;
90. float upx = 0;
91. float upy = 0;
92. @Override
93. public boolean onTouch(View v, MotionEvent event) {
94. int eventtype = event.getAction();
95. Paint paint = new Paint();
96. paint.setColor(Color.GREEN);
97. paint.setStrokeWidth(5);
98. switch (eventtype) {
99. case MotionEvent.ACTION_DOWN:
100. downx = event.getX();
101. downy = event.getY();
102. break;
103. case MotionEvent.ACTION_MOVE:
104. upx = event.getX();
105. upy = event.getY();
106. canvas.drawLine(downx, downy, upx, upy, paint);
107. iv1.invalidate();
108. downx = upx;
109. downy = upy;
110. break;
111. case MotionEvent.ACTION_UP:
112. upx = event.getX();
113. upy = event.getY();
114. canvas.drawLine(downx, downy, upx, upy, paint);
115. iv1.invalidate();
116. break;
117. }
118. return true;
119. }