Android自定義View實現(xiàn)體重表盤詳解流程
效果視頻

分析
起始角度
如下圖所示,起點角度為150,終點角度為240

圓弧
白色圓弧為整個圓弧范圍,藍色圓弧為根據(jù)數(shù)據(jù)變動而覆蓋白色圓弧,藍色圓弧比白色圓弧大一點,突出顯示
InnerArcPaint.setStrokeWidth( Width * (float)0.1 ); OuterArcPaint.setStrokeWidth( Width * (float)0.12 );
指針
中間的水滴指針是一個白色的水滴圖片,下圖藍色為選擇文件的背景顏色(截圖),由于水滴指向-135度,將圖像旋轉(zhuǎn)-75度,水滴尖剛好指向150度的起點。

代碼
初始化屬性
private void InitPaint(){
InnerArcPaint = new Paint( );
InnerArcPaint.setColor( Color.WHITE );
InnerArcPaint.setAntiAlias( true );
InnerArcPaint.setStyle( Paint.Style.STROKE );
OuterArcPaint = new Paint( );
OuterArcPaint.setColor( Color.BLUE );
OuterArcPaint.setAntiAlias( true );
OuterArcPaint.setStyle( Paint.Style.STROKE );
OuterArcPaint.setShadowLayer( (float)10,(float)10,(float)10,Color.parseColor( "#99000000" ) );
TextPaint = new Paint( );
TextPaint.setColor( Color.RED );
TextPaint.setStyle( Paint.Style.STROKE );
TextPaint.setTextSize( 60 );
TextPaint.setStrokeWidth( 2 );
ScalePaint = new Paint( );
ScalePaint.setColor( Color.WHITE );
ScalePaint.setTextSize( 25 );
//硬件加速
setLayerType( LAYER_TYPE_SOFTWARE,null );
}
畫布
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure( widthMeasureSpec, heightMeasureSpec );
int Width = MeasureSpec.getSize( widthMeasureSpec );
InnerArcPaint.setStrokeWidth( Width * (float)0.1 );
OuterArcPaint.setStrokeWidth( Width * (float)0.12 );
oval = new RectF( );
oval.left = Width * (float)0.2;
oval.top = Width * (float)0.2;
oval.right = Width * (float)0.8;
oval.bottom = Width * (float)0.8;
//寬、高一致,使畫布無論邊長如何變化,都成為一個正方形
setMeasuredDimension( Width,Width );
}
繪制內(nèi)圓弧
//繪制內(nèi)圓弧
private void DrawInnerArc(Canvas canvas){
//保存之前的畫布
canvas.save();
canvas.drawArc( oval, StartAngle,SweepAngle,false,InnerArcPaint);
}
繪制外圓弧
//繪制外圓弧
private void DrawOuterArc(Canvas canvas){
canvas.save();
canvas.drawArc( oval, StartAngle,SweepAngle * CurrentData / 300,false,OuterArcPaint);
}
繪制中間指針
//繪制中間指針
private void DrawArrow(Canvas canvas){
canvas.save();
Bitmap bitmap = BitmapFactory.decodeResource( getResources(),R.mipmap.waterdrop );
int width = 75;
int height = 75;
int NewWidth = (int)(getWidth() * 0.08);
float ScaleWidth = (float) (NewWidth / width);
float ScaleHeight = (float) (NewWidth / height);
Matrix matrix = new Matrix( );
//順序不能顛倒
matrix.setRotate( -75 + (SweepAngle * CurrentData / 300),bitmap.getWidth()/2,bitmap.getHeight()/2 );
matrix.postScale( ScaleWidth,ScaleHeight );
Bitmap bitmap1 = Bitmap.createBitmap( bitmap,0,0,width,height,matrix,true );
canvas.drawBitmap( bitmap1,getWidth()/2 - bitmap1.getWidth()/2,getHeight()/2 - bitmap1.getHeight()/2,InnerArcPaint );
bitmap.recycle();
bitmap1.recycle();
}
繪制中間文字
private void DrawCurrentDataText(Canvas canvas){
canvas.save();
Rect rect = new Rect( );
String str = String.valueOf( CurrentData ) + "KG";
TextPaint.setColor( Color.RED );
TextPaint.getTextBounds( str,0,str.length(),rect );
canvas.drawText( str,getWidth()/2 - rect.width()/2,(int)(getHeight() * (float)0.38),TextPaint );
}
繪制左右兩邊文字
private void DrawScaleRightText(Canvas canvas){
canvas.save();
Rect rect = new Rect( );
String str = "300KG";
TextPaint.setTextSize( 45 );
TextPaint.getTextBounds( str,0,str.length(),rect );
TextPaint.setColor( Color.WHITE );
canvas.drawText( str,getWidth()-getWidth()/6,(getHeight()/2+getWidth()/5) ,TextPaint );
}
private void DrawScaleLeftText(Canvas canvas){
canvas.save();
Rect rect = new Rect( );
String str = "0KG";
TextPaint.setTextSize( 45 );
TextPaint.getTextBounds( str,0,str.length(),rect );
TextPaint.setColor( Color.WHITE );
canvas.drawText( str,(getWidth()/2-(getWidth()/3 + 75)),(getHeight()/2+getWidth()/5) ,TextPaint );
}
動畫
public void SetCurrentData(final float data, TimeInterpolator interpolator){
long time = ( (long)Math.abs( data- CurrentData ) *20);
final ValueAnimator valueAnimator = ValueAnimator.ofFloat( CurrentData,data ).setDuration( time );
valueAnimator.setInterpolator( interpolator );
valueAnimator.addUpdateListener( new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
CustomView_ClockDial.this.CurrentData = (float)valueAnimator.getAnimatedValue();
invalidate();
}
} );
valueAnimator.start();
}
全部代碼
public class CustomView_ClockDial extends View {
//內(nèi)圓弧畫筆
private Paint InnerArcPaint;
//外圓弧畫筆
private Paint OuterArcPaint;
//文字畫筆
private Paint TextPaint;
//刻度畫筆
private Paint ScalePaint;
//圓弧范圍
private RectF oval;
//當前數(shù)據(jù)
private float CurrentData = 0;
//起點角度
private float StartAngle = 150;
//終點角度
private float SweepAngle = 240;
public CustomView_ClockDial(Context context) {
super( context );
InitPaint();
}
public CustomView_ClockDial(Context context, @Nullable AttributeSet attrs) {
super( context, attrs );
InitPaint();
}
public CustomView_ClockDial(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super( context, attrs, defStyleAttr );
InitPaint();
}
private void InitPaint(){
InnerArcPaint = new Paint( );
InnerArcPaint.setColor( Color.WHITE );
InnerArcPaint.setAntiAlias( true );
InnerArcPaint.setStyle( Paint.Style.STROKE );
OuterArcPaint = new Paint( );
OuterArcPaint.setColor( Color.BLUE );
OuterArcPaint.setAntiAlias( true );
OuterArcPaint.setStyle( Paint.Style.STROKE );
OuterArcPaint.setShadowLayer( (float)10,(float)10,(float)10,Color.parseColor( "#99000000" ) );
TextPaint = new Paint( );
TextPaint.setColor( Color.RED );
TextPaint.setStyle( Paint.Style.STROKE );
TextPaint.setTextSize( 60 );
TextPaint.setStrokeWidth( 2 );
ScalePaint = new Paint( );
ScalePaint.setColor( Color.WHITE );
ScalePaint.setTextSize( 25 );
//硬件加速
setLayerType( LAYER_TYPE_SOFTWARE,null );
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure( widthMeasureSpec, heightMeasureSpec );
int Width = MeasureSpec.getSize( widthMeasureSpec );
InnerArcPaint.setStrokeWidth( Width * (float)0.1 );
OuterArcPaint.setStrokeWidth( Width * (float)0.12 );
oval = new RectF( );
oval.left = Width * (float)0.2;
oval.top = Width * (float)0.2;
oval.right = Width * (float)0.8;
oval.bottom = Width * (float)0.8;
//寬、高一致,使畫布無論邊長如何變化,都成為一個正方形
setMeasuredDimension( Width,Width );
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw( canvas );
DrawInnerArc(canvas);
DrawOuterArc(canvas);
DrawArrow(canvas);
DrawCurrentDataText(canvas);
DrawScaleRightText(canvas);
DrawScaleLeftText(canvas);
}
//繪制內(nèi)圓弧
private void DrawInnerArc(Canvas canvas){
//保存之前的畫布
canvas.save();
canvas.drawArc( oval, StartAngle,SweepAngle,false,InnerArcPaint);
}
//繪制外圓弧
private void DrawOuterArc(Canvas canvas){
canvas.save();
canvas.drawArc( oval, StartAngle,SweepAngle * CurrentData / 300,false,OuterArcPaint);
}
//繪制中間指針
private void DrawArrow(Canvas canvas){
canvas.save();
Bitmap bitmap = BitmapFactory.decodeResource( getResources(),R.mipmap.waterdrop );
int width = 75;
int height = 75;
int NewWidth = (int)(getWidth() * 0.08);
float ScaleWidth = (float) (NewWidth / width);
float ScaleHeight = (float) (NewWidth / height);
Matrix matrix = new Matrix( );
//順序不能顛倒
matrix.setRotate( -75 + (SweepAngle * CurrentData / 300),bitmap.getWidth()/2,bitmap.getHeight()/2 );
matrix.postScale( ScaleWidth,ScaleHeight );
Bitmap bitmap1 = Bitmap.createBitmap( bitmap,0,0,width,height,matrix,true );
canvas.drawBitmap( bitmap1,getWidth()/2 - bitmap1.getWidth()/2,getHeight()/2 - bitmap1.getHeight()/2,InnerArcPaint );
bitmap.recycle();
bitmap1.recycle();
}
private void DrawCurrentDataText(Canvas canvas){
canvas.save();
Rect rect = new Rect( );
String str = String.valueOf( CurrentData ) + "KG";
TextPaint.setColor( Color.RED );
TextPaint.getTextBounds( str,0,str.length(),rect );
canvas.drawText( str,getWidth()/2 - rect.width()/2,(int)(getHeight() * (float)0.38),TextPaint );
}
private void DrawScaleRightText(Canvas canvas){
canvas.save();
Rect rect = new Rect( );
String str = "300KG";
TextPaint.setTextSize( 45 );
TextPaint.getTextBounds( str,0,str.length(),rect );
TextPaint.setColor( Color.WHITE );
canvas.drawText( str,getWidth()-getWidth()/6,(getHeight()/2+getWidth()/5) ,TextPaint );
}
private void DrawScaleLeftText(Canvas canvas){
canvas.save();
Rect rect = new Rect( );
String str = "0KG";
TextPaint.setTextSize( 45 );
TextPaint.getTextBounds( str,0,str.length(),rect );
TextPaint.setColor( Color.WHITE );
canvas.drawText( str,(getWidth()/2-(getWidth()/3 + 75)),(getHeight()/2+getWidth()/5) ,TextPaint );
}
public void SetCurrentData(final float data, TimeInterpolator interpolator){
long time = ( (long)Math.abs( data- CurrentData ) *20);
final ValueAnimator valueAnimator = ValueAnimator.ofFloat( CurrentData,data ).setDuration( time );
valueAnimator.setInterpolator( interpolator );
valueAnimator.addUpdateListener( new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
CustomView_ClockDial.this.CurrentData = (float)valueAnimator.getAnimatedValue();
invalidate();
}
} );
valueAnimator.start();
}
}
下載鏈接
到此這篇關(guān)于Android自定義View實現(xiàn)體重表盤詳解流程的文章就介紹到這了,更多相關(guān)Android 自定義view內(nèi)容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持腳本之家!
相關(guān)文章
使用PackageManager獲得應(yīng)用信息實例方法
PackageManager是Android中一個很有用的類,能夠獲取已安裝的應(yīng)用(包)的信息,如應(yīng)用名稱、圖標、權(quán)限,安裝、刪除應(yīng)用(包)等2013-11-11
淺談Android應(yīng)用的內(nèi)存優(yōu)化及Handler的內(nèi)存泄漏問題
這篇文章主要介紹了Android應(yīng)用的內(nèi)存優(yōu)化及Handler的內(nèi)存泄漏問題,文中對Activity無法被回收而造成的內(nèi)存泄漏給出了通常的解決方案,需要的朋友可以參考下2016-02-02

