android自定义view，实现竖直方向的文字功能，文字方向朝上，同时提供接口，判断当前touch的是哪个字符，并改变颜色。
由于时间比较仓促，因此没有对代码进行过多的优化，功能远远不如android的自带的TextView强大，只是继承于view，而不是textview。
主要用途：电话本的侧边快速导航等
效果图：（自定义字符串 “#ABCDEFGHIJKLMN），可以实现自定义任意字符串
view的实现：
1 import cn.carbs.verticalstraighttextview.R;
2 import android.content.Context;
3 import android.content.res.TypedArray;
4 import android.graphics.Canvas;
5 import android.graphics.Paint.Align;
6 import android.graphics.Rect;
7 import android.text.TextPaint;
8 import android.util.AttributeSet;
9 import android.util.Log;
10 import android.util.TypedValue;
11 import android.view.View;
12 /**
13 * 参考资料：
14 * http://chris.banes.me/2014/03/27/measuring -text/
15 * http://blog.163.com/gobby_1110/blog/static/2928171520136304172378/
16 * @author Rick.Wang
17 *
18 */
19 public class VerticalStraightTextView extends View {
20
21 private final static int DEFAULT_TEXT_SIZE = 15;
22 private final static int DEFAULT_TEXT_COLOR = 0xFF000000;
23 private final static int DEFAULT_TEXT_COLOR_PICKED = 0xFF990000;
24 private final static int DEFAULT_CHAR_SPACE = 0;
25
26 private TextPaint mTextPaint;
27 private TextPaint mTextPaintPicked;
28 private String mText = "";
29
30 private int mTextLength = 0;
31 private int mCharGap = 0;
32 private int mCharWidth = 0;
33 private int mCharHeight = 0;
34
35 float[] coordinates = null ;
36
37 public float[] getCoordinates(){
38 return coordinates;
39 }
40
41 public VerticalStraightTextView(Context context) {
42 super(context);
43 init();
44 }
45
46 public VerticalStraightTextView(Context context, AttributeSet attrs) {
47 super(context, attrs);
48 init();
49
50 TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.verticalstraighttextview );
51
52 int n = a.getIndexCount();
53 for (int i = 0; i < n; i++) {
54 int attr = a.getIndex(i);
55 switch (attr) {
56 case R.styleable.verticalstraighttextview_text :
57 mText = a.getString(attr);
58 if(mText == null){
59 mText = "";
60 break;
61 }
62 mTextLength = mText .length();
63 break;
64 case R.styleable.verticalstraighttextview_textSize :
65 int textSize = a.getDimensionPixelOffset(R.styleable.verticalstraighttextview_textSize , DEFAULT_TEXT_SIZE);
66 if (textSize > 0) {
67 mTextPaint.setTextSize(textSize);
68 mTextPaintPicked.setTextSize(textSize);
69 }
70 break;
71
72 case R.styleable.verticalstraighttextview_charGap :
73 mCharGap = a.getDimensionPixelSize(R.styleable.verticalstraighttextview_charGap , (int) TypedValue.applyDimension(
74 TypedValue. COMPLEX_UNIT_PX, DEFAULT_CHAR_SPACE, getResources().getDisplayMetrics()));
75 break;
76 case R.styleable.verticalstraighttextview_textColor :
77 mTextPaint .setColor(a.getColor(R.styleable.verticalstraighttextview_textColor, DEFAULT_TEXT_COLOR));
78 break;
79 case R.styleable.verticalstraighttextview_textColorPicked :
80 mTextPaintPicked .setColor(a.getColor(R.styleable.verticalstraighttextview_textColorPicked, DEFAULT_TEXT_COLOR_PICKED ));
81 break;
82 }
83 }
84 a.recycle();
85
86 requestLayout();
87 invalidate();
88 }
89
90 private final void init() {
91 mTextPaint = new TextPaint();
92 mTextPaint.setAntiAlias(true);
93 mTextPaint.setTextSize(DEFAULT_TEXT_SIZE);
94 mTextPaint.setTextAlign(Align.CENTER);
95 mTextPaintPicked = new TextPaint(mTextPaint);
96 mTextPaint.setColor(DEFAULT_TEXT_COLOR);
97 mTextPaintPicked.setColor(DEFAULT_TEXT_COLOR_PICKED);
98 }
99
100 public void setText(String text) {
101 if(text == null){
102 text = "";
103 }
104 if(!mText.equals(text)){
105 mText = text;
106 mTextLength = text.length();
107 requestLayout();
108 invalidate();
109 }
110 }
111
112 public void setTextSize(int size) {
113 if(mTextPaint.getTextSize() != size){
114 mTextPaint.setTextSize(size);
115 mTextPaintPicked.setTextSize(size);
116 requestLayout();
117 invalidate();
118 }
119 }
120
121 public void setTextColor(int color) {
122 if(color != mTextPaint.getColor()){
123 mTextPaint.setColor(color);
124 invalidate();
125 }
126 }
127
128 public void setTextColorPicked(int color) {
129 if(color != mTextPaintPicked.getColor()){
130 mTextPaintPicked.setColor(color);
131 invalidate();
132 }
133 }
134
135 public int getCharHeight(){
136 return mCharGap + mCharHeight;
137 }
138
139 @Override
140 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
141 Log.d("1218" , "onMeasure" );
142 //获取字体宽度
143 float maxCharWidth = 0f;
144 for(int i = 0; i < mTextLength; i++){
145 maxCharWidth = Math.max(mTextPaint.measureText( mText.substring(i, i+1)), maxCharWidth);
146 }
147 mCharWidth = ( int)Math.ceil(maxCharWidth);
148
149 //获取字体高度
150 Rect textBounds = new Rect();
151 mTextPaint.getTextBounds( mText, 0, mTextLength, textBounds);
152 mCharHeight = textBounds.height();
153
154 setMeasuredDimension(measureWidth(widthMeasureSpec), measureHeight(heightMeasureSpec));
155 }
156
157 private int measureWidth(int measureSpec) {
158 int result = 0;
159 int specMode = MeasureSpec.getMode(measureSpec);
160 int specSize = MeasureSpec.getSize(measureSpec);
161
162 if (specMode == MeasureSpec.EXACTLY) {
163 result = specSize;
164 } else {
165 result = this.getPaddingLeft() + this.getPaddingRight() + mCharWidth ;
166 if (specMode == MeasureSpec.AT_MOST) {
167 result = Math. min(result, specSize);
168 }
169 }
170 return result;
171 }
172
173 private int measureHeight(int measureSpec) {
174 int result = 0;
175 int specMode = MeasureSpec.getMode(measureSpec);
176 int specSize = MeasureSpec.getSize(measureSpec);
177
178 if (specMode == MeasureSpec.EXACTLY) {
179 result = specSize;
180 } else {
181 result = getPaddingTop() + getPaddingBottom();
182 if(mTextLength > 0){
183 result += mTextLength * (mCharGap + mCharHeight) - mCharGap ;
184 }
185 if (specMode == MeasureSpec.AT_MOST) {
186 result = Math. min(result, specSize);
187 }
188 }
189 return result;
190 }
191
192 int pickedCharIndex = -1;
193
194 @Override
195 protected void onDraw(Canvas canvas) {
196 super.onDraw(canvas);
197 Log. d("1218", "onDraw");
198 if(mTextLength == 0){
199 return;
200 }
201
202 int height = getMeasuredHeight();
203 int measuredWidth = getMeasuredWidth();
204
205 int paddingTop = getPaddingTop();
206 int paddingBottom = getPaddingBottom();
207 int paddingLeft = getPaddingLeft();
208 int paddingRight = getPaddingRight();
209
210 //默认居中
211 int x = paddingLeft + (measuredWidth - paddingLeft - paddingRight)/2;
212 int y = 0;
213
214 int cellHeight = (height - paddingTop - paddingBottom)/ mTextLength ;
215 //TODO 可能会有bug
216 if(coordinates == null || coordinates. length != mTextLength){
217 coordinates = new float[mTextLength + 1];
218 }
219 coordinates[0] = 0;
220 for(int i = 0; i < mTextLength; i++){
221 y = paddingTop + i * cellHeight + cellHeight/2;
222 coordinates[i + 1] = y + cellHeight/2;
223 if(pickedCharIndex != i){
224 canvas.drawText( mText, i, i + 1, x, y, mTextPaint);
225 } else{
226 canvas.drawText( mText, i, i + 1, x, y, mTextPaintPicked);
227 }
228 }
229 coordinates[mTextLength ] = height;
230 }
231
232 //y is the coordinate-Y
233 //this function can return the "touched char"
234 public int getPickedCharIndex(float[] coordinates, float y){
235 int start = 0;
236 int end = coordinates. length - 1;
237 while (start != end - 1) {
238 int middle = (start + end) / 2;
239 if (y < coordinates[middle]) {
240 end = middle;
241 } else if (y > coordinates[middle]) {
242 start = middle;
243 }
244 }
245 return start;
246 }
247
248 public int getPickedCharIndex(float y){
249 int start = 0;
250 int end = coordinates.length - 1;
251 while (start != end - 1) {
252 int middle = (start + end) / 2;
253 if (y < coordinates [middle]) {
254 end = middle;
255 } else if (y > coordinates[middle]) {
256 start = middle;
257 }
258 }
259 return start;
260 }
261
262 public void setPickedCharIndex(int index){
263 if(pickedCharIndex != index){
264 pickedCharIndex = index;
265 invalidate();
266 }
267 }
268 }
style文件的定义：（将此代码写入values文件夹下的styles.xml文件中）
1 <declare-styleable name="verticalstraighttextview"> 2 <attr name= "text" format ="string" /> 3 <attr name= "textColor" format ="reference|color" /> 4 <attr name= "textColorPicked" format="reference|color" /> 5 <attr name= "textSize" format="reference|dimension" /> 6 <attr name= "charGap" format ="reference|dimension" /> 7 </declare-styleable >
布局文件引入此自定义view：
1 <cn.carbs.verticalstraighttextview.view.VerticalStraightTextView 2 android:id="@+id/kk" 3 android:layout_width="wrap_content" 4 android:padding="5dp" 5 android:layout_height="fill_parent" 6 android:background="#33333333" 7 app:textSize="20sp" 8 app:text= "#ABCEDFGHIJKLMN" />
在activity中的使用：
1 verticalView = (VerticalStraightTextView)this.findViewById(R.id.kk);
2
3 verticalView.setOnClickListener(new View.OnClickListener() {
4 @Override
5 public void onClick(View v) {
6 Toast.makeText(getApplicationContext(), "onclick", Toast.LENGTH_SHORT).show();
7 }
8 });
9
10 verticalView.setOnTouchListener(new View.OnTouchListener() {
11
12 @Override
13 public boolean onTouch(View view, MotionEvent event) {
14 switch(event.getAction()){
15 case MotionEvent.ACTION_DOWN:
16 verticalView.setPickedCharIndex(verticalView.getPickedCharIndex(event.getY()));
17 break;
18 case MotionEvent.ACTION_MOVE:
19 verticalView.setPickedCharIndex(verticalView.getPickedCharIndex(event.getY()));
20 break;
21 case MotionEvent.ACTION_UP:
22 verticalView.setPickedCharIndex(-1);
23 break;
24 case MotionEvent.ACTION_CANCEL:
25 verticalView.setPickedCharIndex(-1);
26 break;
27 }
28 return true;
29 }
30 });
时间： 2024-10-05 06:00:00