package com.loading;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Rect;import android.os.Handler;import android.support.annotation.Nullable;import android.util.AttributeSet;import android.view.View;/** * Created by zhouguizhijxhz on 2018/5/25. */public class LoadingView extends View{ private Paint loadPaint; private Paint paint; private String text = "今日頭條"; private float percent; private Handler handler = new Handler(); public LoadingView(Context context) {  this(context,null); } public LoadingView(Context context, @Nullable AttributeSet attrs) {  this(context, attrs,0); } public LoadingView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {  super(context, attrs, defStyleAttr);  initPaint(); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {  Rect bounds = new Rect();  paint.getTextBounds(text, 0, text.length(), bounds);  setMeasuredDimension(bounds.width(),bounds.height()); } private void initPaint() {  paint = new Paint();  paint.setColor(Color.parseColor("#999999"));  paint.setTextSize(60);  loadPaint = new Paint();  loadPaint.setStyle(Paint.Style.FILL);  loadPaint.setColor(0x70ffffff); } @Override protected void onDraw(Canvas canvas) {  drawText(canvas);  drawLine(canvas); } private void drawLine(Canvas canvas) {  if(null==canvas){   return;  }  canvas.save();  Rect bounds = new Rect();  paint.getTextBounds(text, 0, text.length(), bounds);  Rect rect = new Rect(0, 0, (int) (bounds.width()*percent), bounds.height());  canvas.clipRect(rect);  canvas.drawRect(rect,loadPaint);  canvas.restore();  handler.postDelayed(new Runnable() {   @Override   public void run() {    if(percent>=1.0){     percent=0;    }else{     percent+=0.05f;    }    postInvalidate();   }  },200); } private void drawText(Canvas canvas) {  if(null==canvas){   return;  }  Paint.FontMetricsInt fm = paint.getFontMetricsInt();  canvas.drawText(text, getWidth() / 2 - paint.measureText(text) / 2,    getHeight() / 2 - (fm.bottom + fm.top) / 2, paint); } @Override protected void onWindowVisibilityChanged(int visibility) {  if(visibility==View.VISIBLE){   percent+=0.05f;   invalidate();  } }}