由于安卓應用很廣泛，在工業中也常有一些應用，比如可以用安卓來去工業中的一些數據進行實現的監測，顯示，同時可以做一些自動化控制，當然在這里，我不是做這些自動化控制方面的研究，只是做一個控件，液位指示，其實就是繼承自progressbar,然后重新寫一測量與繪制，算是對自定義控件進行一下復習。
我們要做的最終就是下面這個效果：
在這里，我們要做到對這個指示器的以下屬性可設置：
容器壁的厚度、容器壁的顏色、容器中液體的寬度、液體總高度、液體當前高度的顏色顯示、液體未達到顏色顯示、當前高度的文字指示、指示文字大小的顯示。
對以上屬性的可以設置，會使在實現應用中讓顯示更加直觀人性化。下面就開始我們的指示器的制作。
1.先在項目的res目錄下建一個resouce文件，用來定義自定義的屬性，這些都會在下面給出的源碼中給出，新人可以參考下，老家伙你就繞道吧^^：
<?xml version="." encoding="utf-"?><resources><declare-styleable name="JianWWIndicateProgress"><attr name="progress_height" format="dimension" /><attr name="progress_width" format="dimension" /><attr name="progress_unreachedcolor" format="color" /><attr name="progress_reached_color" format="color" /><attr name="progress_reached_height" format="integer" /><attr name="progress_cheek_width" format="dimension" /><attr name="progress_cheek_color" format="color" /><attr name="progress_reached_textsize" format="dimension" /><attr name="progress_reached_textcolor" format="color" /></declare-styleable></resources>
2.繼承progressbar,這里繼承他主要是為了能夠用progressbar的getProgress()方法得到當前的progress,與setProgress()方法等progress中提供的一些方法，便于對數據的一些處理。
package com.jianww.firstview;import com.example.jwwcallback.R;import android.content.Context;import android.content.res.TypedArray;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Paint.Style;import android.graphics.Rect;import android.util.AttributeSet;import android.util.TypedValue;import android.widget.ProgressBar;public class JianWWIndicateProgress extends ProgressBar {private static final int unreached_color = Xaaff;// 未到達的顏色private static final int reached_color = Xaaff;// 到達顏色private static final int progress_height = ;// 容器中液位的默認高度private static final int progress_width = ;// 容器中液位的寬度private static final int reached_height = ;// 默認到達到達的高度private static final int progress_cheek_width = ;// 容器的邊框寬度private static final int progress_cheek_color = xff;// 容器的邊框顏色private static final int progress_reached_textsize = ;// 指示字體尺寸private static final int progress_reached_textcolor = Xffff;// 指示字體顏色protected int unReachedColor;// 未到達的顏色protected int reachedColor;// 到達顏色protected int progressHeight;// 容器中液位的總高度protected int progressWidth;// 容器中液面的寬度protected int reachedHeight;// 默認液位到達的到達的高度protected int cheekWidth;// 容器的邊框寬度protected int cheekColor;// 容器的邊框顏色protected int reachedTextsize;// 指示字體尺寸protected int reachedTextcolor;// 指示字體顏色protected float widthZoom;protected float heightZoom;/*** dp px**/protected int dppx(int dpVal) {return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dpVal, getResources().getDisplayMetrics());}/*** sp px**/protected int sppx(int spVal) {return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, spVal, getResources().getDisplayMetrics());}private Paint paintCheek = new Paint();private Paint paint = new Paint();private float radio;private float progressNowHeight;public JianWWIndicateProgress(Context context) {this(context, null);}public JianWWIndicateProgress(Context context, AttributeSet asets) {this(context, asets, );}public JianWWIndicateProgress(Context context, AttributeSet asets, int defStyle) {super(context, asets, defStyle);obtainStyledAttributes(asets);// paint.setTextSize(reachedTextsize);// paint.setColor(reachedTextcolor);}/*** 定義屬性* * @param asets屬性*/private void obtainStyledAttributes(AttributeSet asets) {final TypedArray typeArray = getContext().obtainStyledAttributes(asets, R.styleable.JianWWIndicateProgress);unReachedColor = typeArray.getColor(R.styleable.JianWWIndicateProgress_progress_unreachedcolor,unreached_color);reachedColor = typeArray.getColor(R.styleable.JianWWIndicateProgress_progress_reached_color, reached_color);// 到達顏色progressHeight = (int) typeArray.getDimension(R.styleable.JianWWIndicateProgress_progress_height,progress_height);progressWidth = dppx((int) typeArray.getDimension(R.styleable.JianWWIndicateProgress_progress_width, progress_width));// 容器的總寬度reachedHeight = (int) typeArray.getDimension(R.styleable.JianWWIndicateProgress_progress_reached_height,reached_height);// 到達的高度cheekWidth = (int) typeArray.getDimension(R.styleable.JianWWIndicateProgress_progress_cheek_width,progress_cheek_width);// 容器的邊框寬度cheekColor = typeArray.getColor(R.styleable.JianWWIndicateProgress_progress_cheek_color, progress_cheek_color);reachedTextsize = (int) typeArray.getDimension(R.styleable.JianWWIndicateProgress_progress_reached_textsize,progress_reached_textsize);// 指示字體尺寸reachedTextcolor = typeArray.getColor(R.styleable.JianWWIndicateProgress_progress_reached_textcolor,progress_reached_textcolor);// 指示字體顏色typeArray.recycle();}/*** onMeasure是對繪出的控件將來占的空間進行的安排，*/@Overrideprotected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);int totalWidth = measurdWidth(widthMeasureSpec);int totalHeight = measurdHeight(heightMeasureSpec);setMeasuredDimension(totalWidth, totalHeight);}/**** @param widthMeasureSpec* @return 獲取寬度尺寸*/private int measurdWidth(int widthMeasureSpec) {int result = ;int widthSpaceSize = MeasureSpec.getSize(widthMeasureSpec);int widthSpaceMode = MeasureSpec.getMode(widthMeasureSpec);if (widthSpaceMode == MeasureSpec.EXACTLY) {result = widthSpaceSize;widthZoom = widthSpaceSize/(progressWidth+*cheekWidth);progressWidth = (int) (progressWidth * widthZoom);} else if (widthSpaceMode == MeasureSpec.UNSPECIFIED) {result = Math.max(widthSpaceSize, getPaddingLeft() + getPaddingRight() + progressWidth + * cheekWidth);} else if (widthSpaceMode == MeasureSpec.AT_MOST) {result = Math.min(widthSpaceSize, getPaddingLeft() + getPaddingRight() + progressWidth + * cheekWidth);}return result;}/*** * @param heightMeasureSpec* @return獲取高度尺寸*/private int measurdHeight(int heightMeasureSpec) {int result = ;int heightSpaceSize = MeasureSpec.getSize(heightMeasureSpec);int heightSpaceMode = MeasureSpec.getMode(heightMeasureSpec);if (heightSpaceMode == MeasureSpec.EXACTLY) {result = heightSpaceSize;heightZoom = heightSpaceSize/(progressHeight+*cheekWidth);progressHeight = (int) (progressHeight*heightZoom);} else if (heightSpaceMode == MeasureSpec.UNSPECIFIED) {result = Math.max(heightSpaceSize, getPaddingTop() + getPaddingBottom() + progressHeight + * cheekWidth);} else if (heightSpaceMode == MeasureSpec.AT_MOST) {result = Math.min(heightSpaceSize, getPaddingTop() + getPaddingBottom() + progressHeight + * cheekWidth);}return result;}/*** 繪制控件*/@Overrideprotected synchronized void onDraw(Canvas canvas) {super.onDraw(canvas);radio = getProgress() * .f / getMax();progressNowHeight = (int) (progressHeight * radio);// 存繪畫前畫布狀態canvas.save();// 把畫布移動到要繪制的點canvas.translate(getPaddingLeft(), getPaddingRight());// 繪制容器外殼paintCheek.setColor(cheekColor);// 畫筆顏色paintCheek.setAntiAlias(true);// 是否過度paintCheek.setStyle(Style.STROKE);// 空心paintCheek.setStrokeWidth(cheekWidth);// 邊框的寬度canvas.drawRect(cheekWidth/, cheekWidth/, progressWidth + cheekWidth*/, progressHeight + cheekWidth*/,paintCheek);// 繪總液位paint.setColor(unReachedColor);paint.setStyle(Style.FILL);canvas.drawRect(cheekWidth, cheekWidth, progressWidth+cheekWidth, progressHeight+cheekWidth,paint);// 繪當前液位paint.setStyle(Style.FILL);paint.setColor(reachedColor);canvas.drawRect(cheekWidth, cheekWidth + progressHeight - progressNowHeight,progressWidth + cheekWidth, progressHeight + cheekWidth, paint);// 繪液位指示String text = getProgress() + "%";paint.setTextSize(reachedTextsize);paint.setColor(reachedTextcolor);float textHeight = sppx(reachedTextsize)/;if(progressNowHeight >= progressHeight/){canvas.drawText(text, cheekWidth + progressWidth / , cheekWidth + progressHeight - progressNowHeight+textHeight, paint);}else{canvas.drawText(text, cheekWidth + progressWidth / , cheekWidth + progressHeight - progressNowHeight, paint);}canvas.restore();}}3.就是在布局中的引用了
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:tools="http://schemas.android.com/tools"xmlns:jwwprogress="http://schemas.android.com/apk/res-auto"xmlns:app="http://schemas.android.com/apk/res/com.example.jwwcallback"android:layout_width="match_parent"android:layout_height="match_parent"android:gravity="center" ><com.jianww.firstview.JianWWIndicateProgressandroid:id="@+id/jp_progress"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"android:max=""app:progress_cheek_color="#ff"app:progress_cheek_width="dp"app:progress_height="dp"app:progress_reached_color="#ff"app:progress_reached_textcolor="#"app:progress_reached_textsize="sp"app:progress_unreachedcolor="#ff"app:progress_width="dp" /></RelativeLayout>
4.就是在acitivity中的初始化與使用。
package com.example.jwwmain;import java.io.IOException;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.util.Random;import com.example.jwwcallback.R;import com.jianww.firstview.JianWWIndicateProgress;import android.app.Activity;import android.os.Bundle;import android.os.Handler;public class MainActivity extends Activity {private JianWWIndicateProgress jprogress;private int nowProgress;private Handler mHandler = new Handler() {public void handleMessage(android.os.Message msg) {int progress = jprogress.getProgress();jprogress.setProgress(++progress);if (progress >= ) {jprogress.setProgress();}mHandler.sendEmptyMessageDelayed(, );};};@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initView();}private void initView() {jprogress = (JianWWIndicateProgress) findViewById(R.id.jp_progress);mHandler.sendEmptyMessage();}}關于Android中自定義控件之液位指示器的相關知識就給大家介紹到這里，希望對大家有所幫助！
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