Android UI 自定义控件_使用android的fragment碎片控件、textview文本标签控件、recyclerview

自绘控件(图表等无交互的控件)

主要重写onDraw()方法

举个例子：转圆圈的小车

public class CarView extends View {
    private Bitmap carBitmap;
    private Path path;
    
    // 路径计算（主要使用到PathMeasure）
    private PathMeasure pathMeasure; 
    
    private float distanceRatio = 0;

    // 画圆圈的画笔
    private Paint circlePaint;

    // 画小车的画笔
    private Paint carPaint;

    // 针对car bitmap图片操作的矩阵
    private Matrix carMatrix; 
    
    public CarView(Context context) {
        super(context);
        init();
    }

    public CarView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public CarView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    private void init() {
        carBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.icon_car);
        
        path = new Path();
        path.addCircle(0, 0, 200, Path.Direction.CW);
        pathMeasure = new PathMeasure(path, false);
        circlePaint = new Paint();
        circlePaint.setStrokeWidth(5);
        circlePaint.setStyle(Paint.Style.STROKE);
        circlePaint.setAntiAlias(true);
        circlePaint.setColor(Color.BLACK);

        carPaint = new Paint();
        carPaint.setColor(Color.DKGRAY);
        carPaint.setStrokeWidth(2);
        carPaint.setStyle(Paint.Style.STROKE);

        carMatrix = new Matrix();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawColor(Color.WHITE);
        int width = getWidth();
        int height = getHeight();

        // 移动canvas坐标系到中心
        canvas.translate(width / 2, height / 2);
        carMatrix.reset();
        distanceRatio +=  0.006f;
        if(distanceRatio >=1){
            distanceRatio = 0;
        }
//        0 - 1
        float[] pos = new float[2]; //记录位置
        float[] tan = new float[2]; //记录切点值xy
        
        float distance = pathMeasure.getLength() * distanceRatio;
        pathMeasure.getPosTan(distance, pos, tan);

        // 计算小车本身要旋转的角度
        float degree = (float) (Math.atan2(tan[1], tan[0]) * 180 / Math.PI);

        // 设置旋转角度和旋转中心
        carMatrix.postRotate(degree, carBitmap.getWidth() / 2, carBitmap.getHeight() / 2); 
        
        // 这里要将设置到小车的中心点
        carMatrix.postTranslate(pos[0] - carBitmap.getWidth() / 2, pos[1] - carBitmap.getHeight() / 2);
        canvas.drawPath(path, circlePaint);
        canvas.drawBitmap(carBitmap, carMatrix, carPaint);
        invalidate();
    }
}
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组合控件

主要体现封装思想：组合系统控件

继承控件

继承原生控件，重写部分方法

事件类控件

通常需要处理触摸事件

容器类控件

PS：后续补充上其他自定义控件Demo