自学鸿蒙应用开发（44）- 秒表应用开发（2）

自学鸿蒙应用开发（44）- 秒表应用开发（2）

经过几天的开发，秒表应用终于初具规模了，先看执行效果：

秒表应用开发2

指针式秒表组件

下面是自定义指针式模拟秒表组件的实现代码。具体内容参见注释。

//指针式秒表组件类public class AnalogStopWatch extends Component implements Component.DrawTask { private long start_time = 0; //计时开始时刻，毫秒单位 private long millisecond = 0; //计时时间，毫秒单位 private boolean running = false;//执行状态 //构造函数 public AnalogStopWatch(Context context) { super(context); Initialize(null); } //构造函数 public AnalogStopWatch(Context context, AttrSet attrSet) { super(context, attrSet); Initialize(attrSet); } //构造函数 public AnalogStopWatch(Context context, AttrSet attrSet, String styleName) { super(context, attrSet, styleName); Initialize(attrSet); } //构造函数 public AnalogStopWatch(Context context, AttrSet attrSet, int resId) { super(context, attrSet, resId); Initialize(attrSet); } //获取运行状态 public boolean isRunning(){ return running; } //获取当前计时时长 public long getMiliseconds(){ return millisecond; } //根据目前的运行状态，开始或停止计时 public void start_stop(){ if(!running) { start_time = Calendar.getInstance().getTimeInMillis(); millisecond = 0; running = true; onRunTimer(); } else{ running = false; } } //计时Timer void onRunTimer(){ final long delayTime = 100L; //延时时间，毫秒单位 millisecond = Calendar.getInstance().getTimeInMillis() - start_time; invalidate(); //更新画面表示 if(running) { //如果处于运行状态，触发下一次延时执行 TaskDispatcher uiTaskDispatcher = mContext.getUITaskDispatcher(); Revocable revocable = uiTaskDispatcher.delayDispatch(new Runnable() { @Override public void run() { onRunTimer(); } }, delayTime); } } //归零 public void reset(){ if(!running && millisecond > 0) { onResetTimer(); //启动归零处理 } } //归零处理 void onResetTimer(){ final long delayTime = 10L; long second_value = millisecond / 1000 % 60; long minute_value = millisecond / 1000 / 60; if(second_value > 0){ millisecond -= 1000; //秒针反转 } if(minute_value > 0){ millisecond -= 1000 * 60; //分针反转 } if(second_value > 0 || minute_value >0) { //如果反转未到位，触发下次延时处理 TaskDispatcher uiTaskDispatcher = mContext.getUITaskDispatcher(); Revocable revocable = uiTaskDispatcher.delayDispatch(new Runnable() { @Override public void run() { onResetTimer(); } }, delayTime); } else{ millisecond = 0; } invalidate(); } @Override public void onDraw(Component component, Canvas canvas){ Paint paint = new Paint(); RectFloat bound = getBoundRect(); Point main_center = bound.getCenter(); drawScale(canvas, paint, main_center, getRadius(), 1); drawScaleValue(canvas, paint, main_center, getRadius() * 0.8f, 12, 5, (int)(getRadius() * 0.2f)); Point center = new Point(main_center.getPointX(), bound- + getRadius() * 0.6f); float radius = getRadius() / 3; drawScale(canvas, paint, center, radius, 5); drawScaleValue(canvas, paint, center, radius * 0.7f, 12, 5, (int)(radius * 0.25f)); drawDigitalTime(canvas, paint, main_center.getPointX(),main_center.getPointY() + getRadius() * 0.4f); drawMinute(canvas, center, radius); drawSecond(canvas, bound); } //描画刻度线 private void drawScale(Canvas canvas, Paint paint, Point center, float radius, int scale_interval){ paint.setColor(Color.WHITE); float len5sec = radius / 8; float len1sec = radius / 12; float len02sec = radius / 20; paint.setColor(Color.BLACK); for(int i = 0; i < 300; i+= scale_interval){ float insideRaduis = radius; if ((i % 25)==0){ insideRaduis -= len5sec; paint.setStrokeWidth(radius / 60); } else if((i % 5)==0){ insideRaduis -= len1sec; paint.setStrokeWidth(radius / 80); } else{ insideRaduis -= len02sec; paint.setStrokeWidth(radius / 120); } drawRadius(canvas, paint, center, insideRaduis, radius, i * Math.PI / 150); } } //描画全部刻度值 private void drawScaleValue(Canvas canvas, Paint paint, Point center, float radius, int count, int offset, int font_size){ for(int i = 1; i <= count; i++){ drawScaleText(canvas, paint, center, radius, Math.PI * 2 / count * i, offset * i, font_size); } } //描画秒针 private void drawMinute(Canvas canvas, Point center, float radius){ Paint paint = new Paint(); paint.setColor(Color.RED); paint.setStrokeWidth(radius / 20); paint.setStrokeCap(Paint.StrokeCap.ROUND_CAP); drawRadius(canvas, paint, center, 0, radius * 0.9f, millisecond / 60 * Math.PI * 2 / 60000); float oval_radius = radius / 10; canvas.drawOval(new RectFloat(center.getPointX() - oval_radius, center.getPointY() - oval_radius, center.getPointX() + oval_radius, center.getPointY() + oval_radius), paint); } //描画分针 private void drawSecond(Canvas canvas, RectFloat bound){ float radius = getRadius(); Paint paint = new Paint(); paint.setColor(Color.RED); paint.setStrokeWidth(radius / 40); paint.setStrokeCap(Paint.StrokeCap.ROUND_CAP); drawRadius(canvas, paint, bound.getCenter(), 0, radius * 0.9f, millisecond * Math.PI * 2 / 60000); float oval_radius = radius / 20; Point center = bound.getCenter(); canvas.drawOval(new RectFloat(center.getPointX() - oval_radius, center.getPointY() - oval_radius, center.getPointX() + oval_radius, center.getPointY() + oval_radius), paint); } //描画径向直线 private void drawRadius(Canvas canvas, Paint paint, Point center, float from, float to, double angle){ double sin = Math.sin(angle); double cos = Math.cos(angle); canvas.drawLine(new Point(center.getPointX() + (float)(from * sin), center.getPointY() - (float)(from * cos)), new Point(center.getPointX() + (float)(to * sin), center.getPointY() - (float)(to * cos)), paint); } //描画单一刻度值 private void drawScaleText(Canvas canvas, Paint paint, Point center, float radius, double angle, int value, int font_size){ double sin = Math.sin(angle); double cos = Math.cos(angle); Font.Builder builder = new Font.Builder("Arial"); builder.setWeight(Font.REGULAR); paint.setFont(builder.build()); paint.setTextSize(font_size); String text = String.format("%d", value); float width = paint.measureText(text); //计算字符串显示宽度 canvas.drawText(paint, text, center.getPointX() + (float)(radius * sin) - width / 2, center.getPointY() - (float)(radius * cos) + font_size / 3); } //描画数字时间 private void drawDigitalTime(Canvas canvas, Paint paint, float x, float y){ Font.Builder builder = new Font.Builder("Arial"); builder.setWeight(Font.REGULAR); paint.setFont(builder.build()); int font_size = (int)(getRadius() / 4); paint.setColor(Color.BLUE); paint.setTextSize(font_size); String now = String.format("%02d:%02d:%02d", millisecond/1000/3600, //hour millisecond/1000/60%60, //minute millisecond/1000%60); //second float width = paint.measureText(now); //计算字符串显示宽度 canvas.drawText(paint, now, x - width / 2 , y); } //获取秒表显示区域 private RectFloat getBoundRect(){ float width = getWidth(); float height = getHeight(); float size = Math.min(width, height); float x_padding = (width - size) / 2; float y_padding = (height - size) / 2; return new RectFloat(x_padding, y_padding, width - x_padding, height - y_padding); } //获取显示半径 private float getRadius(){ return getBoundRect().getWidth() / 2; } //获取圆心位置 private Point getCenter(){ return getBoundRect().getCenter(); } //初始化 private void Initialize(AttrSet attrSet){ addDrawTask(this); }}

在布局中布置指针式秒表组件

在本应用的布局中，我们使用了指针式秒表组件、两个操作按钮和一个表示计时结果的Text组件：

使用指针式秒表组件

以下是在AbilitySlice中使用指针式秒表组件的示例代码：

public class MainAbilitySlice extends AbilitySlice { AnalogStopWatch stopwatch = null; Text lap_time = null; int record_count = 0; @Override public void onStart(Intent intent) { super.onStart(intent); super.setUIContent(ResourceTable.Layout_ability_main); //秒表组件 stopwatch = (AnalogStopWatch)findComponentById(ResourceTable.Id_analog_stop_watch); //计时结果Text组件 lap_time = (Text)findComponentById(ResourceTable.Id_lap_times); //开始或停止按钮 Button start_stop = (Button)findComponentById(ResourceTable.Id_start_stop); //清零或保存结果按钮 Button reset_lap = (Button)findComponentById(ResourceTable.Id_reset_lap); start_stop.setClickedListener(new Component.ClickedListener() { @Override public void onClick(Component component) { stopwatch.start_stop(); if(stopwatch.isRunning()){ start_stop.setText(ResourceTable.String_Stop); reset_lap.setText(ResourceTable.String_Lap); clearTime(); } else{ start_stop.setText(ResourceTable.String_Start); reset_lap.setText(ResourceTable.String_Reset); recordTime(); } } }); reset_lap.setClickedListener(new Component.ClickedListener() { @Override public void onClick(Component component) { if (stopwatch.isRunning()){ recordTime(); } else{ stopwatch.reset(); clearTime(); } } }); } //清除计时结果 private void clearTime(){ lap_time.setText(""); record_count = 0; } //记录当前时间 private void recordTime(){ String lap_string = lap_time.getText(); long milliseconds = stopwatch.getMiliseconds(); String current_time = String.format("Lap%02d %02d:%02d:%02d.%03d", record_count, milliseconds / 1000 / 60 / 60 % 60, //hour milliseconds / 1000 / 60 % 60, //minute milliseconds / 1000 % 60, //second milliseconds % 1000); //milisecond lap_time.setText(lap_string + "\n" + current_time); record_count++; }}

我们没有在指针式秒钟组件中处理按钮动作，其目的是为了给使用者提供更大的灵活性。

执行结果如下：

参考代码

完整代码可以从以下链接-：

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