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1、概述
比來須要用進度條，秉著不反復造輪子的准繩，上github上搜刮了一番，看了幾個認為比擬悅目的ProgressBar，好比：daimajia的等。簡略看了下代碼，根本都是繼續自View，徹完全底的自界說了一個進度條。盯著那壯麗轉動條，溘然認為，為何要經由過程View去寫一個轉動條，體系曾經供給了ProgressBar和屬於它的特征，我們沒需要從新去構建一個，然則體系的又比擬丑，分歧版本變現還紛歧定一樣。那末得出我們的目的：轉變體系ProgressBar的模樣。
對沒錯，我們沒有需要去從0打造一個ProgressBar，人家固然長的欠好看，然則特征和穩固性照樣方才的，我們只須要為其整下容就ok了。
接上去，我們貼下後果圖：
1、橫向的進度條
2、圓形的進度條
沒錯，這就是我們的進度條後果，橫向的模擬了daimajia的進度條模樣。不外我們繼續子ProgressBar，簡略的為其全部容，代碼清楚易懂 。為何說，易懂呢？
橫向誰人進度條，年夜家會drawLine()和drawText()吧，那末經由過程getWidth()拿到控件的寬度，再經由過程getProgress()拿到進度，按比例掌握繪制線的長短，字的地位還不是分分鐘的事。
2、完成
橫向的轉動條繪制確定須要一些屬性，好比已/未達到進度的色彩、寬度，文本的色彩、年夜小等。
原來呢，我是想經由過程體系ProgressBar的progressDrawable，從外面提取一些屬性完成繪制須要的參數的。然則，終究呢，反而讓代碼變得龐雜。所以終究照樣改用自界說屬性。 說道自界說屬性，年夜家應當曾經不生疏了。
1、HorizontalProgressBarWithNumber
（1）自界說屬性
values/attr_progress_bar.xml:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="HorizontalProgressBarWithNumber">
<attr name="progress_unreached_color" format="color" />
<attr name="progress_reached_color" format="color" />
<attr name="progress_reached_bar_height" format="dimension" />
<attr name="progress_unreached_bar_height" format="dimension" />
<attr name="progress_text_size" format="dimension" />
<attr name="progress_text_color" format="color" />
<attr name="progress_text_offset" format="dimension" />
<attr name="progress_text_visibility" format="enum">
<enum name="visible" value="0" />
<enum name="invisible" value="1" />
</attr>
</declare-styleable>
<declare-styleable name="RoundProgressBarWidthNumber">
<attr name="radius" format="dimension" />
</declare-styleable>
</resources>
（2）結構中獲得
public class HorizontalProgressBarWithNumber extends ProgressBar
{
private static final int DEFAULT_TEXT_SIZE = 10;
private static final int DEFAULT_TEXT_COLOR = 0XFFFC00D1;
private static final int DEFAULT_COLOR_UNREACHED_COLOR = 0xFFd3d6da;
private static final int DEFAULT_HEIGHT_REACHED_PROGRESS_BAR = 2;
private static final int DEFAULT_HEIGHT_UNREACHED_PROGRESS_BAR = 2;
private static final int DEFAULT_SIZE_TEXT_OFFSET = 10;
/**
* painter of all drawing things
*/
protected Paint mPaint = new Paint();
/**
* color of progress number
*/
protected int mTextColor = DEFAULT_TEXT_COLOR;
/**
* size of text (sp)
*/
protected int mTextSize = sp2px(DEFAULT_TEXT_SIZE);
/**
* offset of draw progress
*/
protected int mTextOffset = dp2px(DEFAULT_SIZE_TEXT_OFFSET);
/**
* height of reached progress bar
*/
protected int mReachedProgressBarHeight = dp2px(DEFAULT_HEIGHT_REACHED_PROGRESS_BAR);
/**
* color of reached bar
*/
protected int mReachedBarColor = DEFAULT_TEXT_COLOR;
/**
* color of unreached bar
*/
protected int mUnReachedBarColor = DEFAULT_COLOR_UNREACHED_COLOR;
/**
* height of unreached progress bar
*/
protected int mUnReachedProgressBarHeight = dp2px(DEFAULT_HEIGHT_UNREACHED_PROGRESS_BAR);
/**
* view width except padding
*/
protected int mRealWidth;
protected boolean mIfDrawText = true;
protected static final int VISIBLE = 0;
public HorizontalProgressBarWithNumber(Context context, AttributeSet attrs)
{
this(context, attrs, 0);
}
public HorizontalProgressBarWithNumber(Context context, AttributeSet attrs,
int defStyle)
{
super(context, attrs, defStyle);
setHorizontalScrollBarEnabled(true);
obtainStyledAttributes(attrs);
mPaint.setTextSize(mTextSize);
mPaint.setColor(mTextColor);
}
/**
* get the styled attributes
*
* @param attrs
*/
private void obtainStyledAttributes(AttributeSet attrs)
{
// init values from custom attributes
final TypedArray attributes = getContext().obtainStyledAttributes(
attrs, R.styleable.HorizontalProgressBarWithNumber);
mTextColor = attributes
.getColor(
R.styleable.HorizontalProgressBarWithNumber_progress_text_color,
DEFAULT_TEXT_COLOR);
mTextSize = (int) attributes.getDimension(
R.styleable.HorizontalProgressBarWithNumber_progress_text_size,
mTextSize);
mReachedBarColor = attributes
.getColor(
R.styleable.HorizontalProgressBarWithNumber_progress_reached_color,
mTextColor);
mUnReachedBarColor = attributes
.getColor(
R.styleable.HorizontalProgressBarWithNumber_progress_unreached_color,
DEFAULT_COLOR_UNREACHED_COLOR);
mReachedProgressBarHeight = (int) attributes
.getDimension(
R.styleable.HorizontalProgressBarWithNumber_progress_reached_bar_height,
mReachedProgressBarHeight);
mUnReachedProgressBarHeight = (int) attributes
.getDimension(
R.styleable.HorizontalProgressBarWithNumber_progress_unreached_bar_height,
mUnReachedProgressBarHeight);
mTextOffset = (int) attributes
.getDimension(
R.styleable.HorizontalProgressBarWithNumber_progress_text_offset,
mTextOffset);
int textVisible = attributes
.getInt(R.styleable.HorizontalProgressBarWithNumber_progress_text_visibility,
VISIBLE);
if (textVisible != VISIBLE)
{
mIfDrawText = false;
}
attributes.recycle();
}
嗯，看起來代碼挺長，其實都是在獲得自界說屬性，沒甚麼技巧含量。
（3）onMeasure
適才不是出onDraw外面寫寫就好了麼，為何要改onMeasure呢，重要是由於我們一切的屬性好比進度條寬度讓用戶自界說了，所以我們的丈量也得略微變下。
@Override
protected synchronized void onMeasure(int widthMeasureSpec,
int heightMeasureSpec)
{
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
if (heightMode != MeasureSpec.EXACTLY)
{
float textHeight = (mPaint.descent() + mPaint.ascent());
int exceptHeight = (int) (getPaddingTop() + getPaddingBottom() + Math
.max(Math.max(mReachedProgressBarHeight,
mUnReachedProgressBarHeight), Math.abs(textHeight)));
heightMeasureSpec = MeasureSpec.makeMeasureSpec(exceptHeight,
MeasureSpec.EXACTLY);
}
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
寬度我們不變，所以的自界說屬性不觸及寬度，高度呢，只斟酌不是EXACTLY的情形（用戶明白指定了，我們就不論了），依據padding和進度條寬度算出本身想要的，假如非EXACTLY下，我們停止exceptHeight封裝，傳入給控件停止丈量高度。
丈量完，就到我們的onDraw了~~~
（4）onDraw
@Override
protected synchronized void onDraw(Canvas canvas)
{
canvas.save();
//畫筆平移到指定paddingLeft， getHeight() / 2地位，留意今後坐標都為以此為0，0
canvas.translate(getPaddingLeft(), getHeight() / 2);
boolean noNeedBg = false;
//以後進度和總值的比例
float radio = getProgress() * 1.0f / getMax();
//已達到的寬度
float progressPosX = (int) (mRealWidth * radio);
//繪制的文本
String text = getProgress() + "%";
//拿到字體的寬度和高度
float textWidth = mPaint.measureText(text);
float textHeight = (mPaint.descent() + mPaint.ascent()) / 2;
//假如達到最初，則未達到的進度條不須要繪制
if (progressPosX + textWidth > mRealWidth)
{
progressPosX = mRealWidth - textWidth;
noNeedBg = true;
}
// 繪制已達到的進度
float endX = progressPosX - mTextOffset / 2;
if (endX > 0)
{
mPaint.setColor(mReachedBarColor);
mPaint.setStrokeWidth(mReachedProgressBarHeight);
canvas.drawLine(0, 0, endX, 0, mPaint);
}
// 繪制文本
if (mIfDrawText)
{
mPaint.setColor(mTextColor);
canvas.drawText(text, progressPosX, -textHeight, mPaint);
}
// 繪制未達到的進度條
if (!noNeedBg)
{
float start = progressPosX + mTextOffset / 2 + textWidth;
mPaint.setColor(mUnReachedBarColor);
mPaint.setStrokeWidth(mUnReachedProgressBarHeight);
canvas.drawLine(start, 0, mRealWidth, 0, mPaint);
}
canvas.restore();
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh)
{
super.onSizeChanged(w, h, oldw, oldh);
mRealWidth = w - getPaddingRight() - getPaddingLeft();
}
其實焦點辦法就是onDraw了，然則呢，onDraw也很簡略，繪制線、繪制文本、繪制線，停止。
還有兩個簡略的幫助辦法：
/**
* dp 2 px
*
* @param dpVal
*/
protected int dp2px(int dpVal)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
dpVal, getResources().getDisplayMetrics());
}
/**
* sp 2 px
*
* @param spVal
* @return
*/
protected int sp2px(int spVal)
{
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP,
spVal, getResources().getDisplayMetrics());
}
好了，到此我們的橫向進度就停止了，是否是很簡略~~假如你是自界說View，你還得斟酌progress的更新，斟酌狀況的燒毀與恢復等等龐雜的器械。
接上去看我們的RoundProgressBarWidthNumber圓形的進度條。
2、RoundProgressBarWidthNumber
圓形的進度條和橫向的進度條根本變量都是分歧的，因而我就讓RoundProgressBarWidthNumber extends HorizontalProgressBarWithNumber 了。
然後須要轉變的就是丈量和onDraw了：
完全代碼：
package com.zhy.view;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint.Cap;
import android.graphics.Paint.Style;
import android.graphics.RectF;
import android.util.AttributeSet;
import com.zhy.library.view.R;
public class RoundProgressBarWidthNumber extends
HorizontalProgressBarWithNumber {
/**
* mRadius of view
*/
private int mRadius = dp2px(30);
public RoundProgressBarWidthNumber(Context context) {
this(context, null);
}
public RoundProgressBarWidthNumber(Context context, AttributeSet attrs) {
super(context, attrs);
mReachedProgressBarHeight = (int) (mUnReachedProgressBarHeight * 2.5f);
TypedArray ta = context.obtainStyledAttributes(attrs,
R.styleable.RoundProgressBarWidthNumber);
mRadius = (int) ta.getDimension(
R.styleable.RoundProgressBarWidthNumber_radius, mRadius);
ta.recycle();
mTextSize = sp2px(14);
mPaint.setStyle(Style.STROKE);
mPaint.setAntiAlias(true);
mPaint.setDither(true);
mPaint.setStrokeCap(Cap.ROUND);
}
@Override
protected synchronized void onMeasure(int widthMeasureSpec,
int heightMeasureSpec) {
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int paintWidth = Math.max(mReachedProgressBarHeight,
mUnReachedProgressBarHeight);
if (heightMode != MeasureSpec.EXACTLY) {
int exceptHeight = (int) (getPaddingTop() + getPaddingBottom()
+ mRadius * 2 + paintWidth);
heightMeasureSpec = MeasureSpec.makeMeasureSpec(exceptHeight,
MeasureSpec.EXACTLY);
}
if (widthMode != MeasureSpec.EXACTLY) {
int exceptWidth = (int) (getPaddingLeft() + getPaddingRight()
+ mRadius * 2 + paintWidth);
widthMeasureSpec = MeasureSpec.makeMeasureSpec(exceptWidth,
MeasureSpec.EXACTLY);
}
super.onMeasure(heightMeasureSpec, heightMeasureSpec);
}
@Override
protected synchronized void onDraw(Canvas canvas) {
String text = getProgress() + "%";
// mPaint.getTextBounds(text, 0, text.length(), mTextBound);
float textWidth = mPaint.measureText(text);
float textHeight = (mPaint.descent() + mPaint.ascent()) / 2;
canvas.save();
canvas.translate(getPaddingLeft(), getPaddingTop());
mPaint.setStyle(Style.STROKE);
// draw unreaded bar
mPaint.setColor(mUnReachedBarColor);
mPaint.setStrokeWidth(mUnReachedProgressBarHeight);
canvas.drawCircle(mRadius, mRadius, mRadius, mPaint);
// draw reached bar
mPaint.setColor(mReachedBarColor);
mPaint.setStrokeWidth(mReachedProgressBarHeight);
float sweepAngle = getProgress() * 1.0f / getMax() * 360;
canvas.drawArc(new RectF(0, 0, mRadius * 2, mRadius * 2), 0,
sweepAngle, false, mPaint);
// draw text
mPaint.setStyle(Style.FILL);
canvas.drawText(text, mRadius - textWidth / 2, mRadius - textHeight,
mPaint);
canvas.restore();
}
}
起首獲得它的專有屬性mRadius，然後依據此屬性去丈量，丈量完成繪制；
繪制的進程呢？
先繪制一個細一點的圓，然後繪制一個粗一點的弧度，兩者疊在一路就行。文本呢，繪制在中央~~~整體，沒甚麼代碼量。
好了，兩個進度條就到這了，是否是發明簡略許多。整體設計上，存在些成績，假如抽取一個BaseProgressBar用於獲得公共的屬性；然後分歧模樣的進度條繼續分離完成本身的丈量和模樣，如許構造能夠會清楚些~~~
3、應用
結構文件
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:zhy="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="25dp" >
<com.zhy.view.HorizontalProgressBarWithNumber
android:id="@+id/id_progressbar01"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="50dip"
android:padding="5dp" />
<com.zhy.view.HorizontalProgressBarWithNumber
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="50dip"
android:padding="5dp"
android:progress="50"
zhy:progress_text_color="#ffF53B03"
zhy:progress_unreached_color="#ffF7C6B7" />
<com.zhy.view.RoundProgressBarWidthNumber
android:id="@+id/id_progress02"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="50dip"
android:padding="5dp"
android:progress="30" />
<com.zhy.view.RoundProgressBarWidthNumber
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="50dip"
android:padding="5dp"
android:progress="50"
zhy:progress_reached_bar_height="20dp"
zhy:progress_text_color="#ffF53B03"
zhy:radius="60dp" />
</LinearLayout>
</ScrollView>
MainActivity
package com.zhy.sample.progressbar;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import com.zhy.annotation.Log;
import com.zhy.view.HorizontalProgressBarWithNumber;
public class MainActivity extends Activity {
private HorizontalProgressBarWithNumber mProgressBar;
private static final int MSG_PROGRESS_UPDATE = 0x110;
private Handler mHandler = new Handler() {
@Log
public void handleMessage(android.os.Message msg) {
int progress = mProgressBar.getProgress();
mProgressBar.setProgress(++progress);
if (progress >= 100) {
mHandler.removeMessages(MSG_PROGRESS_UPDATE);
}
mHandler.sendEmptyMessageDelayed(MSG_PROGRESS_UPDATE, 100);
};
};
@Log
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mProgressBar = (HorizontalProgressBarWithNumber) findViewById(R.id.id_progressbar01);
mHandler.sendEmptyMessage(MSG_PROGRESS_UPDATE);
}
}
; public static string GetHtml(string URL, string cookie, out string header, string server)願望本文所述對年夜家的C#法式設計有所贊助。
